Caribbean-On-Line's Caribbean Hurricane Blog



Hurricane Irma

Hurricane Irma Google Map

Published on September 16, 2017 11:19 AM | Comments

Here is a Hurricane Irma Google Map where you can zoom in and see the latest satellite images post Irma.



Video from the British Virgin Islands

Published on September 9, 2017 11:31 PM | Comments



Hurricane Irma Discussion: 11 PM ET Saturday, Sep. 9, 2017

Published on September 9, 2017 11:05 PM | Comments

The long interaction has weakened Irma a bit it seems, which is a sliver of good news for Florida:

Hurricane Irma Discussion Number 44 NWS National Hurricane Center Miami FL AL112017 1100 PM EDT Sat Sep 09 2017

Irma's nearly 24-hour traversal of the north coast of Cuba appears
to have affected the hurricane's structure and intensity. An
earlier NOAA Hurricane Hunter aircraft and a more recent Air Force
reconnaissance flight both measured maximum flight-level winds near
105 kt and surface winds near 95 kt. The planes have reported
a double eyewall structure, which has also been observed in WSR-88D
Doppler radar data from Miami and Key West. Irma's intensity has
been conservatively lowered to 105 kt, and I'd rather wait to lower
the winds further until we've seen the full data set from the Air
Force mission.

Irma has stuttered near the north coast of Cuba for the past few
hours, which may be a harbinger of the north-northwestward turn
that we've been waiting for. In any event, Irma appears to be
moving very slowly toward the northwest, or 305/5 kt, very gradually
shifting away from the north coast of Cuba. With the hurricane
located near a break in the subtropical ridge, it should turn
north-northwestward soon and accelerate near or along the west
coast of Florida during the next 36-48 hours. Because of Irma's
hesitation to move northwestward, the new track guidance has shifted
ever so slightly westward, and the new NHC track is just a little
left of the previous one. Although it is likely that the eye will
move near or over the Lower Keys Sunday morning, the hurricane's
angle of approach to the west coast of Florida makes it very
difficult to pinpoint exactly where Irma will cross the Florida Gulf
coast.

If an eyewall replacement occurs within the next 6-12 hours, Irma
has an opportunity to restrengthen a bit while it moves across the
Straits of Florida. After that time, however, southwesterly shear
is expected to increase to 25-30 kt in about 24 hours and then
continue increasing through 48 hours. This shear, in addition to
Irma's core interacting with Florida, is likely to cause a
weakening trend after 24 hours. The new intensity guidance calls
for an adjustment from the previous forecast, although it
conservatively lies near the upper bound of the reliable models.
Irma is still expected to approach the Florida Keys and Florida
west coast as a major hurricane, and combined with its large size,
will produce significant storm surge flooding in those areas.


KEY MESSAGES:

1. Irma is expected bring life-threatening wind and storm surge to
the Florida Keys and southwestern Florida as an extremely dangerous
major hurricane tonight through Sunday. Preparations in the Florida
Keys and southwest Florida should be complete since tropical-storm-
force winds are already affecting portions of the coast.

2. There is an imminent danger of life-threatening storm surge
flooding in portions of central and southern Florida, including the
Florida Keys, where a Storm Surge Warning is in effect. The threat
of catastrophic storm surge flooding is highest along the southwest
coast of Florida, where 10 to 15 feet of inundation above ground
level is expected. This is a life-threatening situation, and
everyone in these areas should immediately follow any evacuation
instructions from local officials.

3. Irma will bring life-threatening wind impacts to much of Florida
regardless of the exact track of the center. Wind hazards from Irma
are also expected to spread northward through much of Georgia
and portions of South Carolina and Alabama.

4. Irma is expected to produce very heavy rain and inland flooding.
Total rain accumulations of 10 to 20 inches, with isolated amounts
of between 20 and 25 inches, are expected over the Florida Keys, the
Florida peninsula, and southeast Georgia from Saturday through
Monday. Significant river flooding is possible in these areas. Early
next week Irma will also bring periods of heavy rain to much of the
southeast United States where an average of 2 to 6 inches is
forecast, with isolated higher amounts, from North and South
Carolina to Tennessee and eastern Alabama. This includes some
mountainous areas which are more prone to flash flooding. Residents
throughout the southeast states should remain aware of the flood
threat and stay tuned to forecasts and warnings.

FORECAST POSITIONS AND MAX WINDS

INIT 10/0300Z 23.5N 81.0W 105 KT 120 MPH
12H 10/1200Z 24.7N 81.7W 110 KT 125 MPH
24H 11/0000Z 26.8N 82.4W 105 KT 120 MPH
36H 11/1200Z 29.5N 83.4W 80 KT 90 MPH...ON THE COAST
48H 12/0000Z 32.2N 85.0W 55 KT 65 MPH...INLAND
72H 13/0000Z 35.3N 89.0W 25 KT 30 MPH...POST-TROP/INLAND
96H 14/0000Z 37.0N 88.5W 20 KT 25 MPH...POST-TROP/INLAND
120H 15/0000Z...DISSIPATED




Tropical Tidbits: Saturday Morning Update on Hurricane Irma

Published on September 9, 2017 11:02 PM | Comments



Pictures of St. Thomas and St. John after Hurricane Irma

Published on September 8, 2017 11:54 PM | Comments

Some photos from around the web - if anyone has a copyright complaint just let me know and they will be removed:

The airport terminal in St. Thomas
The airport terminal in St. Thomas

The Frenchtown Post Office, St. Thomas
The Frenchtown Post Office

Wharfside Village in Cruz Bay, St. John
Wharfside Village in Cruz Bay, St. John

St. John passenger ferry dock
St. John passenger ferry dock

The Lumberyard, Cruz Bay, St. John
The Lumber Yard, Cruz Bay, St. John

Beachfront in Cruz Bay, St. John
Beachfront in Cruz Bay, St. John



Hurricane Irma Makes Landfall in Cuba

Published on September 8, 2017 11:35 PM | Comments

Somehow, after spinning half over a mountainous Caribbean islands for hours, Irma regained category 5 strength and made landfall along Cuba's coast over the Sabana-Camag├╝ey archipelago - the first category 5 storm to make landfall on Cuba in almost 100 years.

20170909_033216_sport_goes16_abi_conus_11p20um.gif

The 11 p.m. NHC discussion:

Hurricane Irma Discussion Number 40
NWS National Hurricane Center Miami FL AL112017
1100 PM EDT Fri Sep 08 2017

An Air Force Hurricane Hunter flight has found that Irma has
re-intensified to category 5 strength. The plane measured a
maximum flight-level wind of 154 kt and SFMR winds of 140-145 kt in
the northwestern eyewall, so the initial intensity is raised to 140
kt. The hurricane is producing very deep convection in all
quadrants around the eye, which the Air Force flight measured to be
35 n mi wide.

Apparently the ridge to the north of Irma has been stronger than
expected, and the initial motion remains westward, or 280/11 kt.
The track guidance continues to insist on Irma turning
west-northwestward soon, moving along the Cuban Keys adjacent to
the north coast of Cuba during the next 24 hours. After that time,
Irma is expected to turn sharply north-northwestward and accelerate
after 48 hours, moving parallel to the west coast of Florida and
then into Georgia. Mainly because Irma's eye has not deviated from
its westward motion, the new NHC forecast track has again shifted
slightly westward. Because of the hurricane's angle of approach to
the west coast of Florida, it is extremely difficult to pinpoint
exactly where the center might move onshore.

If the eye continues to move over the Cuban Keys and does not move
inland over the main island of Cuba, then Irma would likely not
lose much intensity during the next day or so. As we've stated
many times, fluctuations in intensity are likely during the next 36
hours due to possible and unpredictable eyewall replacement cycles.
After 36 hours, there are some indications that vertical shear may
increase over the hurricane, and a little more weakening is
anticipated at that time. Because of the concerns in the track
forecast noted above, Irma would be able to maintain a strong
intensity for a longer period of time if the center stays off the
west Florida coast. Regardless, Irma is still expected to be a
dangerous hurricane as it approaches the Florida Keys and the west
coast of Florida through 48 hours.

KEY MESSAGES:

1. Irma will continue to bring life-threatening wind, storm surge,
and rainfall hazards to portions of the Bahamas and the north coast
of Cuba, especially over the adjacent Cuban Keys, through Saturday.

2. Irma is expected to make landfall in Florida as an extremely
dangerous major hurricane, and will bring life-threatening wind
impacts to much of the state regardless of the exact track of the
center.

3. There is the danger of life-threatening storm surge inundation in
portions of central and southern Florida, including the Florida
Keys, during the next 36 hours, where a Storm Surge Warning is in
effect. The threat of significant storm surge flooding along the
southwest coast of Florida has increased, and 8 to 12 feet of
inundation above ground level is possible in this area. This is a
life-threatening situation. Everyone in these areas should take all
actions to protect life and property from rising water and follow
evacuation instructions from local officials.

4. Irma is expected to produce very heavy rain and inland flooding.
Total rain accumulations of 8 to 15 inches, with isolated amounts of
20 inches are expected over the Florida Keys and much of the Florida
peninsula through Tuesday night. Irma will likely bring periods of
heavy rain to much of the Florida Panhandle, Georgia, South
Carolina, and western North Carolina early next week, including some
mountainous areas which are more prone to flash flooding. All areas
seeing heavy rainfall from Irma will experience a risk of flooding
and flash flooding.

FORECAST POSITIONS AND MAX WINDS

INIT 09/0300Z 22.1N 77.7W 140 KT 160 MPH
12H 09/1200Z 22.6N 79.1W 140 KT 160 MPH
24H 10/0000Z 23.3N 80.6W 135 KT 155 MPH
36H 10/1200Z 24.5N 81.4W 130 KT 150 MPH
48H 11/0000Z 26.5N 81.9W 115 KT 130 MPH...INLAND
72H 12/0000Z 31.6N 83.8W 50 KT 60 MPH...INLAND
96H 13/0000Z 35.0N 87.0W 25 KT 30 MPH...INLAND
120H 14/0000Z 35.5N 87.5W 20 KT 25 MPH...POST-TROP/INLAND



Tropical Tidbits, Thursday, September 7

Published on September 7, 2017 11:03 PM | Comments

Hurricane Irma is a beast - there is no getting around it. Heed the warnings, prepare if you have a chance. The Turks and Caicos are getting slammed tonight.



Video of Hurricane Irma

Published on September 7, 2017 8:29 PM | Comments

From The Guardian website:



Tropical Tidbits, Wednesday, September 6

Published on September 6, 2017 10:26 PM | Comments

Another sobering update from the excellent Tropical Tidbits:



Video and updates on Irma's wake

Published on September 6, 2017 7:14 PM | Comments

Some not too details video above from several islands. Looking at news reports, there is at least one fatality on Barbuda, with reports there of near total devastation, 90% of structures damaged and most likely every vehicle flooded.


The trail of destruction is just coming to light, I am sure Thursday morning will be very sobering in the leeward and Virgin Islands. St. Martin/Maarten, St. Barts, and Anguilla also appear to have been hit very hard with some additional fatalities reported on St. Martin.




Irma Update

Published on September 6, 2017 2:01 PM | Comments

So Hurricane Irma is still chugging through the Virgin Islands at this moment. Antigua, Barbuda, the French West Indies, BVI and USVI all looked to take a major hit. There are pictures and videos circulating around the web of the damage but I really don't want to post things here that are not verified.

Below is the radar from the NWS in San Juan and the webcam at Marriott Frenchman's Reef at the same time. The cam stopped sending live images right about this time. This is a major catastrophe - we just hope everyone is safe.

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Marriott-Frenchmans-Reef.png




Hurricane Irma Discussion Number 30

Published on September 6, 2017 10:56 AM | Comments

So basically instruments to measure the wind are being blown away...

Hurricane Irma Discussion Number 30 NWS National Hurricane Center Miami FL AL112017 1100 AM AST Wed Sep 06 2017

The eye of Irma passed over Barbuda, St. Barthelemy, and St. Martin
this morning, and will be moving over portions of the British and
U.S. Virgin Islands shortly. A NOAA National Ocean Service
observing site on Barbuda measured sustained winds of 103 kt with a
gust to 135 kt earlier this morning before the anemometer failed.
The station also reported a minimum pressure of 916.1 mb. A minimum
pressure of 915.9 mb was reported on St. Barthelemy. An Air Force
reconnaissance aircraft that performed a single pass through the eye
this morning reported SFMR winds of 152 kt in the northwestern
eyewall around 12Z. Assuming there are stronger winds in the
northeastern eyewall, the initial intensity remains 160 kt for this
advisory. Another Air Force aircraft is currently entering the
storm.

Irma is moving west-northwestward or 285/14 kt. A strong high
pressure ridge extending from the central Atlantic westward is
expected to keep Irma moving west-northwestward during the next 2
to 3 days. The track guidance is in good agreement during this
period and the NHC track is along the southern edge of the guidance
envelope in best agreement with the ECMWF and HFIP corrected
consensus model. After that time, a shortwave trough moving
southward over the east-central United States is expected to erode
the western portion of the ridge. As a result, Irma is forecast to
turn northwestward and northward, but there is still a fair amount
of uncertainty regarding the exact timing and location of
recurvature. The NHC forecast has been shifted eastward to be in
better agreement with the latest model guidance, however it should
be noted that there are numerous GEFS and ECMWF ensemble members
that take Irma over and/or west of Florida. The updated NHC track
is in best agreement with the latest ECMWF ensemble mean. Users are
reminded that the average NHC track errors at days 4 and 5 are
about 175 and 225 statue miles, respectively.

Irma is forecast to remain within favorable atmospheric conditions
and over warm waters during the next 3 to 4 days. Therefore, Irma
is likely to remain a very powerful hurricane during this time, and
the NHC intensity forecast is unchanged from the previous advisory
through day 4. Since the 120-h forecast point is now offshore, the
intensity forecast at that time has been adjusted accordingly.

Now that Irma's eye is clearly visible in radar imagery from San
Juan, Tropical Cyclone Updates with hourly position estimates
will be issued starting at 1200 PM AST (1600 UTC).


KEY MESSAGES:

1. Irma is a potentially catastrophic category 5 hurricane and will
bring life-threatening wind, storm surge, and rainfall hazards to
portions of the northern Leeward Islands, including the Virgin
Islands and Puerto Rico today.

2. A hurricane warning is in effect for the northern coast of the
Dominican Republic, the southeastern Bahamas, the Turks and
Caicos, and portions of Haiti, with a hurricane watch in effect for
the central Bahamas and much of Cuba. Irma is likely to bring
dangerous wind, storm surge, and rainfall to some of these areas
tonight through Friday.

3. Irma could directly affect the remainder of the Bahamas and Cuba
as an extremely dangerous major hurricane later this week. Residents
in these areas should monitor the progress of Irma and listen to
advice given by officials.

4. Direct impacts from wind, storm surge, and rainfall are possible
in the Florida Keys and portions of the Florida Peninsula beginning
later this week and this weekend. However, given the forecast
uncertainty at these time ranges, it is too soon to specify the
location and magnitude of these impacts.


FORECAST POSITIONS AND MAX WINDS

INIT 06/1500Z 18.2N 64.0W 160 KT 185 MPH
12H 07/0000Z 19.0N 66.2W 155 KT 180 MPH
24H 07/1200Z 20.2N 69.0W 150 KT 175 MPH
36H 08/0000Z 21.2N 71.7W 145 KT 165 MPH
48H 08/1200Z 21.9N 74.2W 140 KT 160 MPH
72H 09/1200Z 22.9N 78.1W 135 KT 155 MPH
96H 10/1200Z 25.2N 80.0W 125 KT 145 MPH
120H 11/1200Z 29.0N 80.5W 110 KT 125 MPH



11 p.m. Hurricane Irma Discussion, September 5, 2017

Published on September 5, 2017 11:53 PM | Comments

Below is the NHC discussion from 11 p.m. One thing I noticed tonight is that the ECMWF (the European model you hear referred to) looks like it is calling for some landfall in Cuba. This is still a ways off but they are more aggressive to the southern track, and then turn it right up over the middle of Florida. Who knows if that holds (image at 6 days out below).

Hurricane Irma Discussion Number 28 NWS National Hurricane Center Miami FL AL112017 1100 PM AST Tue Sep 05 2017

The satellite view of Irma remains quite spectacular, with an
extremely well-defined eye and a large, symmetrical CDO. Reports
from NOAA and Air Force Hurricane Hunter aircraft indicate that the
central pressure had fallen at about 1 mb per hour since this
morning, although very recently the deepening trend has leveled
off. Based on SFMR-observed winds from the aircraft, the current
intensity remains at 160 kt. The Meteo-France radar imagery
suggests a concentric eyewall structure and observations from the
aircraft hinted at a secondary wind maximum. If an eyewall
replacement becomes more definitive, this would likely halt
additional strengthening, and could even lead to some weakening.
The official intensity forecast is near or above the model
consensus. Given the favorable atmospheric and oceanic environment,
Irma is likely to remain a Category 4 or 5 hurricane for the next
few days.

Latest center fixes from satellite imagery and the aircraft
indicate that Irma is now moving west-northwestward, or 285/13 kt.
A strong ridge extending southwestward from the central Atlantic is
expected to steer Irma west-northwestward during the next couple of
days. A large mid-latitude trough over the eastern United States is
forecast to lift northeastward, allowing the ridge to build westward
and keep Irma on a westward to west-northwestward heading through
Friday. In 4 to 5 days, a small trough diving southward over
the east-central U.S. is expected to weaken the western portion of
the ridge, causing Irma to turn poleward. Some of the dynamical
models have shifted northward a bit from the previous cycle, with
the normally reliable GFS looking like a northeast outlier. The
official track forecast leans toward the ECMWF solution. Users are
reminded to not focus on the exact forecast track, especially at the
longer ranges, since the average NHC track errors are about 175 and
225 statute miles at days 4 and 5, respectively.

KEY MESSAGES:

1. Irma is a potentially catastrophic category 5 hurricane and will
bring life-threatening wind, storm surge, and rainfall hazards to
portions of the northern Leeward Islands, including the Virgin
Islands and Puerto Rico, on Wednesday. Preparations should be
rushed to completion.

2. A Hurricane Warning is in effect for the northern coast of the
Dominican Republic, with hurricane watches for Haiti, the
southeastern Bahamas and the Turks and Caicos. Irma is likely to
bring dangerous wind, storm surge, and rainfall to these areas from
Wednesday night through Friday.

3. Irma could directly affect the remainder of the Bahamas and Cuba
as an extremely dangerous major hurricane later this week. Residents
in these areas should monitor the progress of Irma and listen to
advice given by officials.

4. The chance of direct impacts from Irma beginning later this week
and this weekend from wind, storm surge, and rainfall continues to
increase in the Florida Keys and portions of the Florida Peninsula.
However, it is too soon to specify the timing and magnitude of these
impacts.

FORECAST POSITIONS AND MAX WINDS

INIT 06/0300Z 17.4N 61.1W 160 KT 185 MPH
12H 06/1200Z 18.1N 63.1W 155 KT 180 MPH
24H 07/0000Z 19.1N 65.9W 150 KT 175 MPH
36H 07/1200Z 20.1N 68.5W 145 KT 165 MPH
48H 08/0000Z 21.0N 71.2W 140 KT 160 MPH
72H 09/0000Z 22.0N 76.2W 135 KT 155 MPH
96H 10/0000Z 23.2N 79.5W 125 KT 145 MPH
120H 11/0000Z 25.0N 81.5W 120 KT 140 MPH

Projected track at 6 days out from the ECMWF - Florida is basically blotted out.

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Tropical Tidbits, Tuesday September 5

Published on September 5, 2017 10:11 PM | Comments

Iram is a monster - this is a sobering report:



5 p.m. Irma Update from the NHC, September 5

Published on September 5, 2017 7:27 PM | Comments

Hurricane Irma Discussion Number 27
NWS National Hurricane Center Miami FL AL112017
500 PM AST Tue Sep 05 2017

Irma continues to exhibit a remarkably impressive satellite
presentation. The intensity was increased to 160 kt on the 1800
UTC intermediate public advisory based on a couple of SFMR winds of
160 kt measured in the northeastern eyewall by the Air Force
aircraft just prior to that time. The minimum pressure measured
by a dropsonde in the eye was 926 mb. Irma becomes only the fifth
Atlantic basin hurricane with a peak wind speed of 160 kt or
higher. The others are Allen (1980), the Labor Day Hurricane
of 1935, Gilbert (1988), and Wilma (2005).

The eye of Irma is within range of the Meteo France radar in the
northeastern Caribbean, and recent images show the development of
an outer eyewall, likely the beginning stages of an eyewall
replacement. These changes in inner-core structure will likely
result in fluctuations in intensity during the next couple of days.
Otherwise, increasing upper-ocean heat content and a very favorable
upper-level pattern are expected to allow Irma to remain a category
4 or 5 hurricane during the next several days. Once again, the NHC
forecast shows limited interaction of the hurricane with the islands
of the Greater Antilles.

Fixes from the latest satellite and radar imagery suggest that Irma
is moving a little north of due west or 280/13 kt. A strong ridge
extending southwestward from the central Atlantic is expected to
steer Irma west-northwestward during the couple of days. A large
mid-latitude trough over the eastern United States is forecast to
lift northeastward, allowing the ridge to build westward and keep
Irma on a westward to west-northwestward heading through Friday.
Over the weekend, a shortwave trough diving southward over the
east-central U.S. is expected to weaken the western portion of
the ridge, causing Irma to turn poleward. The dynamical model
guidance is in good agreement through 72 hours, but there is
increasing spread thereafter. The HWRF, UKMET, and ECMWF show a
more southerly track and a sharper turn around day 5, while the GFS
is farther north and east late in the period. The NHC track is near
a consensus of these models and close to the HFIP corrected
consensus. Users are reminded to not focus on the exact forecast
track, especially at the longer ranges, since the average NHC track
errors are about 175 and 225 statute miles at days 4 and 5,
respectively.

KEY MESSAGES:

1. Irma is a potentially catastrophic category 5 hurricane and will
bring life-threatening wind, storm surge, and rainfall hazards to
portions of the northeastern Leeward Islands tonight and tomorrow.
These hazards will spread into the Virgin Islands and Puerto
Rico tomorrow. Preparations should be rushed to completion before
the arrival of tropical-storm force winds tomorrow morning in Virgin
Islands and Puerto Rico.

2. A hurricane warning is in effect for the northern coast of the
Dominican Republic, with hurricane watches for Haiti, the
southeastern Bahamas and the Turks and Caicos. Irma is likely to
bring dangerous wind, storm surge, and rainfall to these areas from
Wednesday night through Friday.

3. Irma could directly affect the remainder of the Bahamas and Cuba
as an extremely dangerous major hurricane later this week. Residents
in these areas should monitor the progress of Irma and listen to
advice given by officials.

4. The chance of direct impacts from Irma beginning later this week
and this weekend from wind, storm surge, and rainfall continues to
increase in the Florida Keys and portions of the Florida Peninsula.
However, it is too soon to specify the timing and magnitude of these
impacts.

FORECAST POSITIONS AND MAX WINDS

INIT 05/2100Z 17.1N 59.8W 160 KT 185 MPH
12H 06/0600Z 17.6N 61.8W 155 KT 180 MPH
24H 06/1800Z 18.5N 64.6W 150 KT 175 MPH
36H 07/0600Z 19.5N 67.3W 145 KT 165 MPH
48H 07/1800Z 20.4N 70.1W 140 KT 160 MPH
72H 08/1800Z 21.6N 75.3W 135 KT 155 MPH
96H 09/1800Z 22.7N 79.3W 125 KT 145 MPH
120H 10/1800Z 24.4N 81.5W 120 KT 140 MPH



Hurricane Irma 5 Day Cone

Published on September 5, 2017 4:43 PM | Comments



Hurricane Irma Now a Strong Category 5 Storm

Published on September 5, 2017 3:52 PM | Comments

There isn't a lot to say - if you are in the storm's path rush to complete preparations:

BULLETIN Hurricane Irma Intermediate Advisory Number 26A NWS National Hurricane Center Miami FL AL112017 200 PM AST Tue Sep 05 2017

...POTENTIALLY CATASTROPHIC CATEGORY 5 HURRICANE IRMA HEADING
TOWARD THE LEEWARD ISLANDS...
...PREPARATIONS SHOULD BE NEARING COMPLETION IN THE EASTERNMOST
LEEWARD ISLANDS...


SUMMARY OF 200 PM AST...1800 UTC...INFORMATION
----------------------------------------------
LOCATION...16.9N 59.1W
ABOUT 180 MI...290 KM E OF ANTIGUA
ABOUT 185 MI...295 KM ESE OF BARBUDA
MAXIMUM SUSTAINED WINDS...185 MPH...295 KM/H
PRESENT MOVEMENT...W OR 275 DEGREES AT 14 MPH...22 KM/H
MINIMUM CENTRAL PRESSURE...926 MB...27.34 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

None

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Hurricane Warning is in effect for...
* Antigua, Barbuda, Anguilla, Montserrat, St. Kitts, and Nevis
* Saba, St. Eustatius, and Sint Maarten
* Saint Martin and Saint Barthelemy
* British Virgin Islands
* U.S. Virgin Islands
* Puerto Rico, Vieques, and Culebra

A Hurricane Watch is in effect for...
* Guadeloupe
* Dominican Republic from Cabo Engano to the northern border with
Haiti
* Haiti from the northern border with the Dominican Republic to Le
Mole St. Nicholas
* Turks and Caicos Islands
* Southeastern Bahamas

A Tropical Storm Warning is in effect for...
* Guadeloupe
* Dominica

A Tropical Storm Watch is in effect for...
* Dominican Republic from south of Cabo Engao to Isla Saona
* Haiti from south of Le Mole St. Nicholas to Port-Au-Prince

A Hurricane Warning means that hurricane conditions are expected
somewhere within the warning area. A warning is typically issued
36 hours before the anticipated first occurrence of tropical-storm-
force winds, conditions that make outside preparations difficult or
dangerous. In this case, for some of easternmost islands, the
hurricane conditions are expected within the next 12 to 24 hours.
Preparations to protect life and property should be rushed to
completion.

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area.

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.

Interests elsewhere in the Dominican Republic and Haiti, as
well as Cuba, the central and northwestern Bahamas, and Florida
should monitor the progress of Irma.

For storm information specific to your area in the United
States, including possible inland watches and warnings, please
monitor products issued by your local National Weather Service
forecast office. For storm information specific to your area outside
the United States, please monitor products issued by your national
meteorological service.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
At 200 PM AST (1800 UTC), the eye of Hurricane Irma was located near
latitude 16.9 North, longitude 59.1 West. Irma is moving toward the
west near 14 mph (22 km/h), and this general motion is expected to
continue today, followed by a turn toward the west-northwest
tonight. On the forecast track, the extremely dangerous core of Irma
is forecast to move over portions of the northern Leeward Islands
tonight and early Wednesday.

Reports from an Air Force Hurricane Hunter aircraft indicate that
the maximum sustained winds have increased to near 185 mph (295
km/h) with higher gusts. Irma is an extremely dangerous category
5 hurricane on the Saffir-Simpson Hurricane Wind Scale. Some
fluctuations in intensity are likely during the next day or two, but
Irma is forecast to remain a powerful category 4 or 5 hurricane
during the next couple of days.

Hurricane-force winds extend outward up to 60 miles (95 km) from
the center and tropical-storm-force winds extend outward up to 160
miles (260 km).

The latest minimum central pressure reported by reconnaissance
aircraft is 926 mb (27.34 inches).


HAZARDS AFFECTING LAND
----------------------
STORM SURGE: The combination of a life-threatening storm surge and
large breaking waves will raise water levels by as much as 7 to 11
feet above normal tide levels along the coasts of the extreme
northern Leeward Islands within the hurricane warning area near and
to the north of the center of Irma. Near the coast, the surge will
be accompanied by large and destructive waves.

The combination of a life-threatening storm surge and the tide will
cause normally dry areas near the coast to be flooded by rising
waters moving inland from the shoreline. The water is expected to
reach the following heights above ground if the peak surge occurs at
the time of high tide...

British and U.S. Virgin Islands except St. Croix...7 to 11 ft
Northern coast of Puerto Rico...3 to 5 ft
Southern coast of Puerto Rico and St. Croix...1 to 2 ft

The deepest water will occur along the immediate coast in areas of
onshore winds, where the surge will be accompanied by large and
destructive waves. Surge-related flooding depends on the relative
timing of the surge and the tidal cycle, and can vary greatly over
short distances. For information specific to your area, please see
products issued by your local National Weather Service forecast
office.

WIND: Hurricane conditions are expected within the hurricane
warning area in the Leeward Islands by tonight, with tropical storm
conditions beginning late this afternoon or evening. Tropical storm
conditions are expected within the tropical storm warning area where
hurricane conditions are also possible. Hurricane conditions are
expected to begin within the hurricane warning area in the British
and U.S. Virgin Islands and Puerto Rico on Wednesday, with tropical
storm conditions beginning tonight.

Hurricane and tropical storm conditions are possible within the
watch area in the Dominican Republic, Haiti, the Turks and Caicos,
and the southeastern Bahamas by early Thursday.

RAINFALL: Irma is expected to produce total rain accumulations
of 8 to 12 inches with isolated maximum amounts of 18 inches across
the northern Leeward Islands. Irma is expected to produce total
rain accumulations of 4 to 10 inches with isolated maximum amounts
of 15 inches across northeast Puerto Rico and the British and U.S.
Virgin Islands, and amounts of 2 to 4 inches over southwest Puerto
Rico, the southern Leeward Islands, and Saint Croix. This rainfall
may cause life-threatening flash floods and mudslides.

SURF: Swells generated by Irma will affect the northern Leeward
Islands, Puerto Rico, and the U.S. and British Virgin Islands
during the next several days. These swells are likely to cause
life-threatening surf and rip current conditions. Please consult
products from your local weather office.



Hurricane Irma Images

Published on September 5, 2017 3:44 PM | Comments

Going to start keeping some images of and from the effects of Irma on this entry as I find them.

Here's Irma tonight off of Puerto Rico, just about 24 hours later than the same image further down the page:

20170907.0215.goes13.x.ir1km_bw.11LIRMA.160kts-916mb-191N-660W.100pc.jpg


NWS radar at almost 11 a.m. as Irma approaches the Virgin Islands:

11amUSVIradar.png

Sapphire Beach, St. Thomas USVI at 10 a.m. Wednesday morning:

saphhire-beach-st.thomas-10-a.m.jpg

St. Barts radar image, just past midnight:

compo_radar.jpg


Hurricane Irma on Tuesday night, September 5, 2017 as she approaches Barbuda.

hurricane-irma-barbuda.jpg



IRMA BECOMES AN EXTREMELY DANGEROUS CATEGORY 5 HURRICANE

Published on September 5, 2017 9:29 AM | Comments

The 8 a.m. update from the NHC:

BULLETIN Hurricane Irma Special Advisory Number 25 NWS National Hurricane Center Miami FL AL112017 800 AM AST Tue Sep 05 2017

...IRMA BECOMES AN EXTREMELY DANGEROUS CATEGORY 5 HURRICANE...
...PREPARATIONS SHOULD BE RUSHED TO COMPLETION IN THE HURRICANE
WARNING AREA...


SUMMARY OF 800 AM AST...1200 UTC...INFORMATION
----------------------------------------------
LOCATION...16.7N 57.7W
ABOUT 270 MI...440 KM E OF ANTIGUA
ABOUT 280 MI...445 KM ESE OF BARBUDA
MAXIMUM SUSTAINED WINDS...175 MPH...280 KM/H
PRESENT MOVEMENT...W OR 280 DEGREES AT 14 MPH...22 KM/H
MINIMUM CENTRAL PRESSURE...929 MB...27.44 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

The government of the Dominican Republic has issued a Hurricane
Watch from Cabo Engano to the northern border with Haiti and a
Tropical Storm Watch from south of Cabo Engao to Isla Saona.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Hurricane Warning is in effect for...
* Antigua, Barbuda, Anguilla, Montserrat, St. Kitts, and Nevis
* Saba, St. Eustatius, and Sint Maarten
* Saint Martin and Saint Barthelemy
* British Virgin Islands
* U.S. Virgin Islands
* Puerto Rico, Vieques, and Culebra

A Hurricane Watch is in effect for...
* Guadeloupe
* Dominican Republic from Cabo Engano to the northern border with
Haiti

A Tropical Storm Warning is in effect for...
* Guadeloupe
* Dominica

A Tropical Storm Watch is in effect for...
* Dominican Republic from south of Cabo Engao to Isla Saona

A Hurricane Warning means that hurricane conditions are expected
somewhere within the warning area. A warning is typically issued
36 hours before the anticipated first occurrence of tropical-storm-
force winds, conditions that make outside preparations difficult or
dangerous. In this case, for some of easternmost islands, the
hurricane conditions are expected within the next 24 hours.
Preparations to protect life and property should be rushed to
completion.

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area in this case within 36
hours.

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.

Interests elsewhere in the Dominican Republic, along with Haiti,
the Turks and Caicos Islands, Cuba, and the southeastern and central
Bahamas should monitor the progress of Irma.

For storm information specific to your area in the United
States, including possible inland watches and warnings, please
monitor products issued by your local National Weather Service
forecast office. For storm information specific to your area outside
the United States, please monitor products issued by your national
meteorological service.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
At 800 AM AST (1200 UTC), the distinct eye center of Hurricane Irma
was located near latitude 16.7 North, longitude 57.7 West. Irma is
moving toward the west near 14 mph (22 km/h), and this general
motion is expected to continue today, followed by a turn toward the
west-northwest tonight. On the forecast track, the dangerous core of
Irma will move near or over portions of the northern Leeward Islands
tonight and early Wednesday.

Reports from NOAA and U.S. Air Force Hurricane Hunter aircraft
indicate Irma continues to strengthen and maximum sustained winds
have increased to near 175 mph (280 km/h) with higher gusts. Irma
is an extremely dangerous category 5 hurricane on the Saffir-Simpson
Hurricane Wind Scale. Some fluctuations in intensity are likely
during the next day or two, but Irma is forecast to remain a
powerful category 4 or 5 hurricane during the next couple of days.

Hurricane-force winds extend outward up to 45 miles (75 km) from the
center and tropical-storm-force winds extend outward up to 140 miles
(220 km).

The latest estimated minimum central pressure from aircraft data is
929 mb (27.44 inches).


HAZARDS AFFECTING LAND
----------------------
STORM SURGE: The combination of a dangerous storm surge and large
breaking waves will raise water levels by as much as 7 to 11 feet
above normal tide levels along the coasts of the extreme northern
Leeward Islands within the hurricane warning area near and to the
north of the center of Irma. Near the coast, the surge will be
accompanied by large and destructive waves.

The combination of a dangerous storm surge and the tide will cause
normally dry areas near the coast to be flooded by rising waters
moving inland from the shoreline. The water is expected to reach
the following heights above ground if the peak surge occurs at the
time of high tide...

British and U.S. Virgin Islands except St. Croix...7 to 11 ft
Northern coast of Puerto Rico...2 to 4 ft
Southern coast of Puerto Rico and St. Croix...1 to 2 ft

The deepest water will occur along the immediate coast in areas of
onshore winds, where the surge will be accompanied by large and
destructive waves. Surge-related flooding depends on the relative
timing of the surge and the tidal cycle, and can vary greatly over
short distances. For information specific to your area, please see
products issued by your local National Weather Service forecast
office.

WIND: Hurricane conditions are expected within the hurricane
warning area in the Leeward Islands by tonight, with tropical storm
conditions beginning later today. Tropical storm conditions are
expected within the tropical storm warning area where hurricane
conditions are also possible. Hurricane conditions are expected
to begin within the hurricane warning area in the British and U.S.
Virgin Islands and Puerto Rico on Wednesday, with tropical storm
conditions beginning tonight. Hurricane and tropical storm
conditions are possible within the watch area in the Dominican
Republic by early Thursday.

RAINFALL: Irma is expected to produce total rainfall accumulations
of 4 to 8 inches with isolated maximum amounts of 12 inches across
the northern Leeward Islands, the British and U.S. Virgin Islands,
and Puerto Rico. These rainfall amounts may cause life-threatening
flash floods and mudslides.

SURF: Swells generated by Irma will affect the northern Leeward
Islands, Puerto Rico, and the U.S. and British Virgin Islands
during the next several days. These swells are likely to cause
life-threatening surf and rip current conditions. Please consult
products from your local weather office.



Irma update, Monday evening

Published on September 4, 2017 10:58 PM | Comments

Another excellent synopsis from Tropical Tidbits:



Hurricane Irma track continues to push south

Published on September 4, 2017 12:58 PM | Comments

The track is getting worse for Hispaniola and Cuba - better if you are in the northern Bahamas. But there are a lot of factors in play and the forecasters don't sound too confident right now past the 48/72 hour mark.

irma-track-september-4.png




Warnings up for the Leeward Islands, watches for the Virgin Islands

Published on September 4, 2017 12:37 PM | Comments

Iram solidifies as a threat to the Caribbean - watches have moved to warnings and more watches have been issued:

BULLETIN Hurricane Irma Advisory Number 21 NWS National Hurricane Center Miami FL AL112017 1100 AM AST Mon Sep 04 2017

...HURRICANE WARNINGS ISSUED FOR PORTIONS OF THE LEEWARD ISLANDS...
...HURRICANE WATCHES ISSUED FOR THE BRITISH AND U.S. VIRGIN ISLANDS
AND PUERTO RICO...


SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...16.8N 53.3W
ABOUT 560 MI...905 KM E OF THE LEEWARD ISLANDS
MAXIMUM SUSTAINED WINDS...120 MPH...195 KM/H
PRESENT MOVEMENT...WSW OR 255 DEGREES AT 14 MPH...22 KM/H
MINIMUM CENTRAL PRESSURE...944 MB...27.88 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

The government of Antigua has issued a Hurricane Warning for the
islands of Antigua, Barbuda, Anguilla, Montserrat, St. Kitts, and
Nevis. A Hurricane Watch has been issued for the British Virgin
Islands.

The government of the Netherlands has issued a Hurricane Warning for
the islands of Saba, St. Eustatius, and Sint Maarten.

The government of France has issued a Hurricane Warning for St.
Martin and Saint Barthelemy. A Hurricane Watch has been issued for
Guadeloupe.

A Hurricane Watch has been issued for the U.S. Virgin Islands,
Puerto Rico, Vieques, and Culebra.

The government of Barbados has issued a Tropical Storm Watch for
Dominica.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Hurricane Warning is in effect for...
* Antigua, Barbuda, Anguilla, Montserrat, St. Kitts, and Nevis
* Saba, St. Eustatius, and Sint Maarten
* Saint Martin and Saint Barthelemy

A Hurricane Watch is in effect for...
* Guadeloupe
* British Virgin Islands
* U.S. Virgin Islands
* Puerto Rico, Vieques, and Culebra

A Tropical Storm Watch is in effect for...
* Dominica

A Hurricane Warning means that hurricane conditions are expected
somewhere within the warning area. A warning is typically issued
36 hours before the anticipated first occurrence of tropical-storm-
force winds, conditions that make outside preparations difficult or
dangerous. Preparations to protect life and property should be
rushed to completion.

A Hurricane Watch means that hurricane conditions are possible
within the watch area. A watch is typically issued 48 hours before
the anticipated first occurrence of tropical-storm-force winds,
conditions that make outside preparations difficult or dangerous.

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.

Interests in the Dominican Republic, Haiti, the Turks and Caicos
Islands, and the southeastern Bahamas should monitor the progress of
Irma.

For storm information specific to your area in the United States,
including possible inland watches and warnings, please monitor
products issued by your local National Weather Service forecast
office. For storm information specific to your area outside the
United States, please monitor products issued by your national
meteorological service.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
At 1100 AM AST (1500 UTC), the eye of Hurricane Irma was located
near latitude 16.8 North, longitude 53.3 West. Irma is moving toward
the west-southwest near 14 mph (22 km/h). A turn toward the west
is expected later today, followed by a west-northwestward turn late
Tuesday. On the forecast track, the center of Irma will move near
or over portions of the northern Leeward Islands Tuesday night
and early Wednesday.

Maximum sustained winds are near 120 mph (195 km/h) with higher
gusts. Irma is a category 3 hurricane on the Saffir-Simpson
Hurricane Wind Scale. Additional strengthening is forecast through
Tuesday night.

Hurricane-force winds extend outward up to 35 miles (55 km) from the
center and tropical-storm-force winds extend outward up to 140 miles
(220 km).

The estimated minimum central pressure based on data from a NOAA
Hurricane Hunter aircraft is 944 mb (27.88 inches).


HAZARDS AFFECTING LAND
----------------------
STORM SURGE: The combination of a dangerous storm surge and large
breaking waves will raise water levels by as much as 6 to 9 feet
above normal tide levels along the coasts of the extreme northern
Leeward Islands within the hurricane warning area near and to the
north of the center of Irma. Near the coast, the surge will be
accompanied by large and destructive waves.

WIND: Hurricane conditions are expected within the hurricane
warning area by Tuesday night, with tropical storm conditions
expected by late Tuesday. Hurricane conditions are possible within
the hurricane watch area by late Wednesday, with tropical storm
conditions possible by early Wednesday.

RAINFALL: Irma is expected to produce total rainfall accumulations
of 3 to 6 inches across the Leeward Islands, with isolated maximum
amounts of 10 inches across the northern Leeward Islands. These
rainfall amounts may cause life-threatening flash floods and
mudslides.

SURF: Swells generated by Irma will affect the northern Leeward
Islands during the next several days. These swells are likely to
cause life-threatening surf and rip current conditions. Please
consult products from your local weather office.

Also news from the U.S. Virgin Islands as a local statement has been released:

Hurricane Irma Local Statement Advisory Number 21...CORRECTED PRZ001>013-VIZ001-002-042315-

Hurricane Irma Local Statement Advisory Number 21...CORRECTED
National Weather Service San Juan PR AL112017
1125 AM AST Mon Sep 4 2017

...A hurricane watch has been issued for Puerto Rico and US Virgin
Islands...

NEW INFORMATION
---------------

* CHANGES TO WATCHES AND WARNINGS:
- A Hurricane Watch has been issued for all Puerto Rico and US
Virgin Islands.

* CURRENT WATCHES AND WARNINGS:
- A Hurricane Watch is in effect for all Puerto Rico and US Virgin
Islands.

* STORM INFORMATION:
- About 840 miles east of San Juan PR or about 770 miles east of
Saint Thomas VI
- 16.8N 53.3W
- Storm Intensity 120 mph
- Movement West-southwest or 255 degrees at 14 mph

SITUATION OVERVIEW
------------------

Irma is expected to remain as a major hurricane as it approaches Puerto
Rico and the U.S Virgin Islands Wednesday afternoon into Thursday. Irma
could cause dangerous winds, storm surge and rainfall impacts across
the local isles. Hurricane Force winds are possible across Northern
U.S. Virgin Islands, Culebra and Northeast Puerto Rico with strong
tropical force winds likely. The rest of the area likely to experience
tropical storm force winds. Wind gusts with hurricane force wind
are likely at higher elevations. The earliest reasonable time of
tropical storm winds is Wednesday morning. Rainfall accumulations
between 4 to 8 with isolated amounts over 10 inches likely
Wednesday through Thursday.

POTENTIAL IMPACTS
-----------------

* WIND:
Prepare for dangerous wind having possible significant impacts.
Potential impacts in this area include:
- Some damage to roofing and siding materials, along with damage
to porches, awnings, carports, and sheds. A few buildings
experiencing window, door, and garage door failures. Mobile
homes damaged, especially if unanchored. Unsecured lightweight
objects become dangerous projectiles.
- Several large trees snapped or uprooted, but with greater
numbers in places where trees are shallow rooted. Several
fences and roadway signs blown over.
- Some roads impassable from large debris, and more within urban
or heavily wooded places. A few bridges, causeways, and access
routes impassable.
- Scattered power and communications outages, but more prevalent
in areas with above ground lines.

* FLOODING RAIN:
Prepare for life-threatening rainfall flooding having possible
extensive impacts across PUERTO RICO AND THE US VIRGIN ISLANDS.
Potential impacts include:
- Major rainfall flooding may prompt many evacuations and rescues.
- Rivers and tributaries may rapidly overflow their banks in
multiple places. Small streams, creeks, canals, arroyos, and
ditches may become dangerous rivers. In mountain areas,
destructive runoff may run quickly down valleys while
increasing susceptibility to rockslides and mudslides. Flood
control systems and barriers may become stressed.
- Flood waters can enter many structures within multiple
communities, some structures becoming uninhabitable or washed
away. Many places where flood waters may cover escape routes.
Streets and parking lots become rivers of moving water with
underpasses submerged. Driving conditions become dangerous.
Many road and bridge closures with some weakened or washed out.

* SURGE:
Prepare for life-threatening surge having possible significant impacts
across the Atlantic shorelines. Potential impacts in this area
include:
- Areas of inundation with storm surge flooding accentuated by
waves. Damage to several buildings, mainly near the coast.
- Sections of near-shore escape routes and secondary roads become
weakened or washed out, especially in usually vulnerable low
spots.
- Major beach erosion with heavy surf breaching dunes. Strong and
numerous rip currents.
- Moderate damage to marinas, docks, boardwalks, and piers.
Several small craft broken away from moorings, especially in
unprotected anchorages.

* TORNADOES:
Prepare for a tornado event having possible limited impacts across
PUERTO RICO AND THE US VIRGIN ISLANDS. Potential impacts include:
- The occurrence of isolated tornadoes can hinder the execution
of emergency plans during tropical events.
- A few places may experience tornado damage, along with power
and communications disruptions.
- Locations could realize roofs peeled off buildings, chimneys
toppled, mobile homes pushed off foundations or overturned,
large tree tops and branches snapped off, shallow-rooted trees
knocked over, moving vehicles blown off roads, and small boats
pulled from moorings.

PRECAUTIONARY/PREPAREDNESS ACTIONS
----------------------------------

* EVACUATIONS:
For those under evacuation orders, leave as soon as practical
with a destination in mind. Gas up your vehicle well ahead of
time. Be sure that you take all essential materials from your
emergency supplies kit. Let others know where you are going and
when you intend to arrive.

If evacuating the area, stick to prescribed evacuation routes.
Look for additional traffic information on roadway smart signs and
listen to select radio channels for further travel instructions.
Drivers should not use cell phones while operating vehicles.

For those not under evacuation orders, understand that there are
inherent risks to evacuation (such as traffic congestion,
accidents, and driving in bad weather), so evacuate only if
necessary. Help keep roadways open for those that are under
evacuation orders.

If you are exceptionally vulnerable to wind or water hazards from
tropical systems, consider voluntary evacuation, especially if
being officially recommended. Relocate to a predetermined shelter
or safe destination.

If evacuating away from the area or relocating to a nearby
shelter, leave early before weather conditions become hazardous.

* OTHER PREPAREDNESS INFORMATION:
Now is the time to check your emergency plan and take necessary
actions to secure your home or business. Deliberate efforts should be
underway to protect life and property. Ensure that your Emergency
Supplies Kit is stocked and ready.

When making safety and preparedness decisions, do not focus on the
exact forecast track as there are inherent forecast uncertainties
which must be taken into account.

If you live in a place that is particularly vulnerable to high wind,
such as a mobile home, an upper floor of a high rise building, or on
a boat, plan to move to safe shelter. Take enough supplies for you
and your family for several days.

If you live in a place particularly vulnerable to flooding, such as
near the ocean or a large inland lake, in a low lying or poor
drainage area, in a valley or canyon, or near an already swollen
river, plan to move to safe shelter on higher ground

Always heed the advice of local officials and comply with any orders
that are issued. Do not needlessly jeopardize your life or the lives
of others.

When securing your property, outside preparations should be conducted
as soon as possible before conditions deteriorate. The onset of
strong gusty winds and heavy rain can cause certain preparedness
activities to become unsafe.

Be sure to let friends and other family members know of your
intentions and whereabouts for surviving the storm. For emergency
purposes, have someone located away from the threatened area serve as
your point of contact. Share vital contact information with others.
Keep cell phones handy and well charged.

Be a Good Samaritan and check on those who may not be fully aware of
the situation or who are unable to make personal preparations.

Visitors to the area should become familiar with nearby surroundings.
If you are a visitor, know the name of the county or parish in which
you are located and where it is relative to current watches and
warnings. If staying at a hotel, ask the management staff about their
onsite disaster plan. Listen for evacuation orders, especially
pertaining to area visitors.

Closely monitor NOAA Weather Radio or other local news outlets for
official storm information. Listen for possible changes to the
forecast.



Tropical Tidbits, Sunday September 3

Published on September 3, 2017 9:28 PM | Comments

The track continues to move a little further south, and earlier today hurricane watches went up in some of the leeward islands:



BULLETIN Hurricane Irma Advisory Number 17

Published on September 3, 2017 12:12 PM | Comments

From the NHC, 11 AM update:


000
WTNT31 KNHC 031450
TCPAT1

BULLETIN
Hurricane Irma Advisory Number 17
NWS National Hurricane Center Miami FL AL112017
1100 AM AST Sun Sep 03 2017

...CATEGORY THREE HURRICANE IRMA MOVING WEST-SOUTHWESTWARD...
...INTERESTS IN THE LEEWARD ISLANDS SHOULD MONITOR THE PROGRESS
OF IRMA...


SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...17.7N 48.4W
ABOUT 885 MI...1420 KM E OF THE LEEWARD ISLANDS
MAXIMUM SUSTAINED WINDS...115 MPH...185 KM/H
PRESENT MOVEMENT...WSW OR 255 DEGREES AT 14 MPH...22 KM/H
MINIMUM CENTRAL PRESSURE...969 MB...28.62 INCHES


WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.

Interests in the Leeward Islands should monitor the progress of
Irma. Hurricane and Tropical Storm Watches will likely be required
for portions of these islands later today or tonight.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
At 1100 AM AST (1500 UTC), the center of Hurricane Irma was located
near latitude 17.7 North, longitude 48.4 West. Irma is moving toward
the west-southwest near 14 mph (22 km/h) and this course at a
slightly slower forward speed is expected through tonight. A turn
toward the west is forecast on Monday.

Maximum sustained winds are near 115 mph (185 km/h) with higher
gusts. Irma is a category 3 hurricane on the Saffir-Simpson
Hurricane Wind Scale. Some strengthening is forecast during the
next 48 hours.

Hurricane-force winds extend outward up to 25 miles (35 km) from the
center and tropical-storm-force winds extend outward up to 80 miles
(130 km).

The estimated minimum central pressure is 969 mb (28.62 inches).

HAZARDS AFFECTING LAND
----------------------
None


NEXT ADVISORY
-------------
Next complete advisory at 500 PM AST.

$$
Forecaster Brown




European Model

Published on September 3, 2017 12:03 PM | Comments

This is the ECMWF model from today, for Thursday - 96 hours out. This does not look great for the Virgin Islands (and others). Again, this is a model and it is 4 days out - but it does show a real chance of this thing blasting by just above if not through the Virgin Islands.

ecmwf-mena-ensemble.png



Irma update from Tropical Tidbits

Published on September 3, 2017 11:42 AM | Comments

Tropical Tidbits is a blog by Levi Cowan of FSU - he makes some informative videos. This is from Saturday the 2nd:



Hurricane Irma

Published on September 1, 2017 3:53 PM | Comments

On the heels of Harvey, who caused major devastation in the United States (and is still dumping rain as a post-tropical depression), we now have Irma. This storm is forecast to become another major hurricane, and it looks like it could potentially impact the Caribbean region - perhaps off the leeward islands by the middle of next week.

We'll be updating on this one regularly until the Caribbean is in the clear.

Hurricane Irma Discussion Number 9 NWS National Hurricane Center Miami FL AL112017 1100 AM AST Fri Sep 01 2017

Irma is undergoing an eyewall replacement cycle. The small eye is
becoming less distinct, with both microwave and visible imagery
indicating the presence of a forming outer eyewall. Satellite
intensity estimates are lower, so the initial wind speed is reduced
to 95 kt. Some further weakening is possible over the next day or
so while Irma moves over marginally warm SSTs and continues the
eyewall replacement. After that time, the environment should be
generally conducive for some restrengthening, although forecasting
the timing of eyewall replacement cycles is next to impossible. The
biggest change from yesterday are the long-term wind shear
predictions from the global models, which shows a little more shear.
Still, the shear is not that strong, and the hurricane will be
moving over 29C SSTs. Thus, the NHC intensity forecast is reduced
somewhat from the previous one, but remains near or slightly above
the model consensus.

Irma has turned a little bit to the left, now estimated to be
moving 285/11. The general synoptic situation remains well
established due to a building mid-level high, which should cause
the hurricane to turn westward later today and then move
west-southwestward through the weekend. An upper-level low will be
dropping southward on the east side of that high, and should be a
key feature to how far south Irma goes before eventually turning
westward and west-northwestward early next week. There is a
noticeable clustering of guidance by day 5, with the ECMWF, HWRF and
corrected-consensus models to the south, and the UKMET, GFS, CTC and
HMON to the north. Since Irma is forecast to be a vertically deep
cyclone, it seems more likely to respond to the northerly flow from
the upper-level low, which leads me to believe the track will be on
the southern side of the guidance. Thus, the forecast will stay
similar to the previous one, very close to the southern cluster
mentioned above.