The NHC is keeping eyes on this thing:
The chances of tropical storm formation and not that high, but worth watching:
TROPICAL WEATHER OUTLOOK NWS NATIONAL HURRICANE CENTER MIAMI FL 800 PM EDT WED AUG 20 2014
For the North Atlantic...Caribbean Sea and the Gulf of Mexico:
1. Shower and thunderstorm activity associated with an elongated area of low pressure located several hundred miles east of the Windward Islands is slowly becoming better organized. Additional development is possible during the next day or two, and a tropical depression could form as the system moves west-northwestward at 10 to 15 mph across the Lesser Antilles and into the Caribbean Sea. After that time, land interaction could limit development potential over the weekend. Regardless of tropical cyclone formation, gusty winds and heavy rainfall are possible across portions of the Lesser Antilles, Puerto Rico, and the Virgin Islands on Thursday night and Friday. Interests in those islands should closely monitor the progress of this system. An Air Force Reserve Hurricane Hunter aircraft is scheduled to investigate the low tomorrow afternoon, if necessary. * Formation chance through 48 hours...medium...50 percent. * Formation chance through 5 days...high...70 percent.
Below is the NHC discussion, and some links to news - sorry to have been a little AWOL on this storm, we took a break this weekend and also had server issues!
TROPICAL STORM BERTHA DISCUSSION NUMBER 12 NWS NATIONAL HURRICANE CENTER MIAMI FL AL032014 500 PM EDT SUN AUG 03 2014
After Bertha's cloud pattern became a little better organized earlier today, there has been little change in its overall appearance over the past several hours. There are limited banding features over the eastern semicircle of the circulation, and the deep convection is a little ragged-looking. The upper-level outflow is becoming a little better defined, but there is still some northwesterly shear over the system. The current intensity is kept at 40 kt based on earlier observations from the Hurricane Hunter aircraft. The numerical guidance has become a little less bullish on future strengthening, but the Decay-SHIPS model still calls for the cyclone to become a hurricane in 60-72 hours, as does the official forecast. It should be noted, however, that the intensity model consensus no longer predicts Bertha to become a hurricane.
Based on an earlier center fix from the aircraft, the working best track has been adjusted a little to the east of the previous estimates. The center location is not obvious on the latest visible imagery, and the initial motion estimate is a somewhat uncertain 325/16 kt. The track forecast for the next 48 hours or so is slightly complicated by a low- to mid-level disturbance that is currently near Florida. The U.K. Met. Office global model forecast shows Bertha interacting with this disturbance and moving a little closer to the United States east coast than earlier runs. Other global models such as the GFS do not show as much interaction and keep Bertha farther offshore. The new official track forecast has been nudged a little to the left of the previous one and is very close to a consensus of the latest GFS and ECMWF solutions.
Some video from Saturday:
Tropical Storm Bertha has formed. We're traveling today, but more updates soon.
TROPICAL STORM BERTHA DISCUSSION NUMBER
3 NWS NATIONAL HURRICANE CENTER MIAMI FL
1100 AM AST FRI AUG 01 2014
Bertha is disorganized this morning. While satellite imagery shows a well-defined low-cloud swirl exposed just west of the main convective mass, reports from an Air Force Reserve Hurricane Hunter Aircraft show that the wind field more resembles that of an open wave. The aircraft did report 56 kt winds at 1500 feet to the east-northeast of the center, along with an area of SFMR surface winds in excess of 40 kt. Based on this, the initial intensity is increased to 45 kt.
The initial motion is now 295/18, and over the past few hours Bertha may be moving even faster. The cyclone is currently being steered by the flow around the Atlantic subtropical ridge and this should continue for the next 48 hours or so. After that time, the cyclone is expected to turn northward into a break in the ridge caused by a deep-layer trough over the eastern United States. This should be followed by recurvature into the westerlies over the Atlantic north of Bermuda. The track guidance remains in good agreement with this scenario, and it has changed little since the previous advisory. The new forecast track is therefore an update of the previous forecast.
Bertha is currently experiencing about 15-20 kt of southwesterly vertical wind shear. and water vapor imagery shows dry mid-/upper-level air near the storm. The forecast track calls for Bertha to interact with one or two upper-level troughs during the next 48-72 hours, which should cause some shear and dry air entrainment to continue. This, combined with the current lack of organization, suggests little change in strength should occur during the next 48 hours or so. After that time, Bertha is expected to move into an environment of less shear and greater moisture. The intensity forecast calls for modest strengthening during that time, but it is weaker than all of the guidance except the Florida State Superensemble. An alternative scenario is that a combination of shear, dry air entrainment, and land interaction causes Bertha to degenerate to a tropical wave during the next 48 hours, followed by possible regeneration in the 72-120 hours when the system reaches the more favorable environment.
SPECIAL TROPICAL WEATHER OUTLOOK NWS NATIONAL HURRICANE CENTER MIAMI FL 415 PM EDT THU JUL 31 2014
For the North Atlantic...Caribbean Sea and the Gulf of Mexico:
1. A Hurricane Hunter aircraft has continued to investigate the low pressure system located about 500 miles east of the Windward Islands. Observations from the aircraft indicate that this system is producing winds of up to 40 to 45 mph in the northern portion of the circulation. Showers and thunderstorms could redevelop over the low tonight or Friday, which could result in tropical cyclone formation. Regardless of development, winds of gale force are likely to spread across portions of the Lesser Antilles beginning early Friday. Interests in the Lesser Antilles should continue to monitor the progress of this disturbance as it moves west-northwestward near 20 mph, and watches or warnings may be required for some of these islands later tonight or Friday. * Formation chance through 48 hours...high...70 percent. * Formation chance through 5 days...high...70 percent.
Not expected to turn into much - but could bring some rain and wind to the islands:
TROPICAL DEPRESSION TWO DISCUSSION NUMBER 1 NWS NATIONAL HURRICANE CENTER MIAMI FL AL022014 500 PM AST MON JUL 21 2014
The area of low pressure in the tropical Atlantic has shown an
increase in convective organization today. Despite the fact that the
convection remains somewhat shallow, it has enough coverage and
organization to classify the system as a tropical cyclone. An ASCAT
pass around 1210 UTC was not conclusive in regards to whether the
surface circulation was closed, but given the persistence of the
convection, we are assuming that the circulation is closed and
are initiating advisories at this time.
The initial intensity of 30 kt is based on data from the ASCAT pass.
The environment is marginal, at best, for development during the
next couple of days, as the depression will be moving over marginal
SSTs and into a region characterized by dry air and subsidence as it
approaches the Caribbean Sea. Most of the global model guidance and
the HWRF shows the system weakening and dissipating by 48 to 72
hours. The official forecast follows suit, but the cyclone could
dissipate sooner than shown here. The SHIPS and LGEM intensity
forecasts seem much too high in this scenario, and are not given
much weight in the official forecast.
The initial motion is quickly toward the west or 280/14 knots. The
cyclone will be steered by the Atlantic subtropical ridge during its
life span, and should remain on a westward to west-northwestward
heading with an increase in forward speed. The NHC track forecast is
close to a blend of the HWRF and the GEFS ensemble mean. Note that
the global models are having a difficult time tracking the small
vortex, and confidence in the details of the track forecast is lower
FORECAST POSITIONS AND MAX WINDS
INIT 21/2100Z 11.6N 43.8W 30 KT 35 MPH
12H 22/0600Z 11.9N 45.8W 30 KT 35 MPH
24H 22/1800Z 12.3N 48.2W 30 KT 35 MPH
36H 23/0600Z 12.8N 51.0W 30 KT 35 MPH
48H 23/1800Z 13.4N 54.2W 30 KT 35 MPH
72H 24/1800Z 15.0N 61.0W 30 KT 35 MPH...POST-TROP/REMNT LOW
The new 5 day graphic explained by the NHC:
Arthur has become a hurricane - the first of the season. It is no threat to the Caribbean.
HURRICANE ARTHUR DISCUSSION NUMBER 10 NWS NATIONAL HURRICANE CENTER MIAMI FL AL012014 500 AM EDT THU JUL 03 2014
Data from NOAA and Air Force Reserve Hurricane Hunter aircraft
indicate that Arthur has reached hurricane strength. Both aircraft
showed several SFMR winds of 60 to 63 kt southeast of the center,
and the NOAA aircraft reported a peak flight-level wind of 79 kt at
8,000 feet. Based on these data the initial intensity is set to 65
kt. Radar data show that Arthur was still having difficulty
maintaining an eyewall overnight, likely due to dry mid/upper-level
air being entrained into the storm. However, the overall radar
presentation has improved during the past couple of hours. Some
gradual intensification is forecast during the next 24 hours while
the cyclone is in an environment of low shear and moves over warm
waters. After that time, however, the shear increases dramatically
as Arthur interacts with a deep-layer baroclinic zone moving off
of the east coast of North America, and global model fields show
Arthur completing extratropical transition by 72 hours. The NHC
intensity forecast is similar to the previous one and remains close
to the multi-model consensus IVCN through 24 hours and is a little
below the consensus after that time.
Radar data and aircraft fixes indicate that the current motion is
now a little east of due north, or 010 degrees at 8 knots. Arthur
should begin to recurve today ahead of the aforementioned deep-layer
trough, and the track model guidance is in good agreement on this
scenario. The NHC track forecast is similar to the previous one and
remains near the middle of the dynamical model envelope and close
to the TVCA multi-model consensus. The official forecast shows the
center of Arthur moving very close to the North Carolina Outer Banks
late tonight and early Friday. Arthur should then accelerate
northeastward offshore of the mid-Atlantic states and the
northeastern U.S. Friday and Friday night, and move into the
Canadian Maritimes by Saturday before turning northward by the end
of the period.
The track, intensity, and wind radii forecast during the
extratropical phase of Arthur have been coordinated with the Ocean
The new experimental potential storm surge flooding map is
available at: www.nhc.noaa.gov/graphics_at1.shtml?inundation
FORECAST POSITIONS AND MAX WINDS
INIT 03/0900Z 31.3N 79.1W 65 KT 75 MPH
12H 03/1800Z 32.5N 78.3W 70 KT 80 MPH
24H 04/0600Z 34.7N 76.1W 75 KT 85 MPH
36H 04/1800Z 37.5N 72.6W 75 KT 85 MPH
48H 05/0600Z 40.9N 67.9W 70 KT 80 MPH
72H 06/0600Z 47.5N 60.0W 50 KT 60 MPH...POST-TROP/EXTRATROP
96H 07/0600Z 54.0N 52.0W 35 KT 40 MPH...POST-TROP/EXTRATROP
120H 08/0600Z 60.0N 50.0W 35 KT 40 MPH...POST-TROP/EXTRATROP
TROPICAL STORM ARTHUR DISCUSSION NUMBER 6
NWS NATIONAL HURRICANE CENTER MIAMI FL AL012014
500 AM EDT WED JUL 02 2014
Despite a somewhat ragged appearance on satellite imagery, Arthur
has strengthened overnight. Data from two ASCAT passes between 02
and 03 UTC showed a broad area of 45-50 kt winds east and northeast
of the center. In addition, NOAA and Air Force Reserve Hurricane
Hunter aircraft have found surface winds in the 45-50 kt range to
the south and northeast of the center, while also finding the
central pressure has fallen to about 996 mb. Based on all of
these data, the initial intensity is set to 50 kt.
Arthur is still suffering the effects of dry air aloft being
entrained into the western half of the circulation, which
features only limited cold cloud tops. The primary convective band
is situated east and southeast of the center, and some semblance of
an eye has been visible in satellite and radar imagery and was
reported by the aircraft. This lopsided structure suggests that
Arthur will not strengthen quickly in the short term. However, given
an otherwise favorable environment of warm water and weak wind
shear, all of the intensity guidance shows the cyclone becoming a
hurricane in 24 to 36 hours, and so does the official forecast. By
72 hours, Arthur will be moving into a high shear environment ahead
of an advancing mid/upper-level trough, which should result in
weakening during the extratropical transition process. The NHC
intensity forecast is close to the intensity consensus aid IVCN
through the period.
Arthur has begun moving steadily northward at around 5 kt. The
overall track forecast reasoning remains unchanged, as the tropical
cyclone should continue northward for the next 12 to 24 hours
and then gradually accelerate northeastward between the
aforementioned trough and a strengthening ridge to the east. The
track guidance envelope has shifted back to the west a little for
this cycle, and the NHC forecast has been adjusted in that
direction, but now lies on the eastern edge of the guidance
envelope through 48 hours.
Given the new NHC forecast, hurricane and tropical storm watches
have been issued for portions of the coasts of South and North
Carolina. Warnings may be required for portions of these areas
This is predicted to be a fast moving storm - and it is the first named storm of the 2014 Atlantic season:
TROPICAL STORM ARTHUR DISCUSSION NUMBER 3 NWS NATIONAL HURRICANE CENTER MIAMI FL AL012014 1100 AM EDT TUE JUL 01 2014
Radar and satellite imagery indicate that the convective
organization of the cyclone has improved since the previous
advisory, and the cyclone is being upgraded based on a sustained
wind report of 33 kt from Settlement Point (SPGF1) on Grand Bahama
Island earlier this morning that was outside of the deep convection.
After remaining nearly stationary earlier this morning, Arthur
appears to to be drifting northwestward now with an uncertain motion
of 315/02 kt. Otherwise, there is no significant change to the
previous forecast track. The latest model guidance has continued the
trend of a pronounced mid-tropospheric trough digging southeastward
from the upper-midwest into the northeastern and mid-Atlantic region
of the United States by 72 hours. The 500 mb flow pattern is almost
identical in the GFS and ECMWF models, which increases the
confidence in this evolving pattern. As a result, a steady increase
in southwesterly steering flow over the southeastern United States
is expected to gradually turn the tropical cyclone northward over
the next 24-36 hours, and then accelerate the system faster toward
the northeast on Thursday and Friday. By Days 4 and 5, Arthur is
forecast to move over the far north Atlantic as an extratropical
cyclone. The NHC track forecast is just an update of the previous
advisory track, and lies down the middle of the tightly packed
guidance envelope close to the consensus model TVCA.
Northwesterly vertical wind shear is forecast by the models to
gradually subside over the next 48 hours, which should allow the
cyclone to develop its own upper-level outflow pattern. In fact,
latest visible and water vapor imagery indicates that cirrus
outflow has been expanding on the north side of the system during
the past few hours, suggesting that the shear conditions could
already be subsiding. The low shear conditions and warm
sea-surface temperatures should allow for at least steady
strengthening, and the cyclone is expected to become a hurricane by
72 hours. The official intensity forecast is similar to the
latest intensity model consensus IVCN through 36 hours, and then
slightly higher after that.
June came and went quietly, July 1 brings the first Tropical Depression of the year. Not a Caribbean threat, but it could become a hurricane on the U.S. East Coast:
000 WTNT31 KNHC 011153 TCPAT1
TROPICAL DEPRESSION ONE INTERMEDIATE ADVISORY NUMBER 2A
NWS NATIONAL HURRICANE CENTER MIAMI FL AL012014
800 AM EDT TUE JUL 01 2014
...DEPRESSION STATIONARY OFFSHORE OF THE COAST OF CENTRAL
SUMMARY OF 800 AM EDT...1200 UTC...INFORMATION
ABOUT 95 MI...155 KM SE OF CAPE CANAVERAL FLORIDA
ABOUT 215 MI...345 KM NNW OF THE NORTHWESTERN BAHAMAS
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
MINIMUM CENTRAL PRESSURE...1007 MB...29.74 INCHES
WATCHES AND WARNINGS
CHANGES WITH THIS ADVISORY...
SUMMARY OF WATCHES AND WARNINGS IN EFFECT...
A TROPICAL STORM WATCH IS IN EFFECT FOR...
* EAST COAST OF FLORIDA FROM FORT PIERCE TO FLAGLER BEACH
A TROPICAL STORM WATCH MEANS THAT TROPICAL STORM CONDITIONS ARE
POSSIBLE WITHIN THE WATCH AREA...IN THIS CASE WITHIN 24 TO 36 HOURS.
INTERESTS ELSEWHERE ALONG THE SOUTHEAST COAST OF THE UNITED STATES
SHOULD MONITOR THE PROGRESS OF THIS SYSTEM.
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 INFORMATION SPECIFIC TO YOUR AREA OUTSIDE OF THE UNITED
STATES...PLEASE MONITOR PRODUCTS ISSUED BY YOUR NATIONAL
DISCUSSION AND 48-HOUR OUTLOOK
AT 800 AM EDT...1200 UTC...THE CENTER OF TROPICAL DEPRESSION ONE
WAS LOCATED NEAR LATITUDE 27.5 NORTH...LONGITUDE 79.2 WEST. THE
DEPRESSION HAS REMAINED NEARLY STATIONARY DURING THE PAST FEW HOURS.
A NORTHWESTWARD MOTION IS EXPECTED TO BEGIN LATER TODAY...FOLLOWED
BY A TURN TOWARD THE NORTH ON WEDNESDAY. ON THE FORECAST TRACK...THE
CENTER OF THE TROPICAL CYCLONE IS EXPECTED TO REMAIN JUST OFFSHORE
AND MOVE EAST OF THE EAST-CENTRAL COAST OF FLORIDA DURING THE NEXT
DAY OR SO. THE SYSTEM IS FORECAST TO PASS EAST OF NORTHEASTERN
FLORIDA ON WEDNESDAY AND WEDNESDAY NIGHT.
MAXIMUM SUSTAINED WINDS ARE NEAR 35 MPH...55 KM/H...WITH HIGHER
GUSTS. SOME STRENGTHENING IS FORECAST DURING THE NEXT 48 HOURS...
AND THE DEPRESSION IS EXPECTED TO BECOME A TROPICAL STORM LATER
TODAY. DURING THE PAST FEW HOURS...SETTLEMENT POINT OBSERVATION SITE
ON GRAND BAHAMA ISLAND REPORTED SUSTAINED WINDS OF 37 MPH...59 KM/H
WITH GUSTS TO 43 MPH...69 KM/H.
THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1007 MB...29.74 INCHES.
TROPICAL WEATHER OUTLOOK NWS NATIONAL HURRICANE CENTER MIAMI FL 800 AM EDT SUN JUN 1 2014
For the North Atlantic...Caribbean Sea and the Gulf of Mexico:
1. An elongated and nearly stationary area of low pressure located over the Bay of Campeche extends northeastward into the south-central Gulf of Mexico. Although shower activity is currently disorganized, some slow development of this disturbance is possible this week as environmental conditions become marginally conducive. * Formation chance through 48 hours...low...near 0 percent * Formation chance through 5 days...low...20 percent
Today marks the first day of the Atlantic hurricane season, which will run until November 30. Long-term averages for the number of named storms, hurricanes, and major hurricanes are 12, 6, and 3, respectively.
The list of names for 2014 is as follows:
This product, the Tropical Weather Outlook, briefly describes significant areas of disturbed weather and their potential for tropical cyclone formation during the next 48 hours. The issuance times of this product are 2 AM, 8 AM, 2 AM, and 8 PM EDT. After the change to standard time in November, the issuance times are 1 AM, 7 AM, 1 PM, and 7 PM EST.
A Special Tropical Weather Outlook will be issued to provide updates, as necessary, in between the regularly scheduled issuances of the Tropical Weather Outlook. Special Tropical Weather Outlooks will be issued under the same WMO and AWIPS headers as the regular Tropical Weather Outlooks.
A standard package of products, consisting of the Tropical Cyclone Public Advisory, the Forecast/Advisory, the Tropical Cyclone Discussion, and the Wind Speed Probabilities, is issued every six hours for all ongoing tropical cyclones. In addition, a Special Advisory package may be issued at any time to advise of significant unexpected changes or to modify watches or warnings.
The Tropical Cyclone Update is a brief statement to inform of significant changes in a tropical cyclone or to post or cancel watches or warnings. It is used in lieu of or to precede the issuance of a special advisory package. The Tropical Cyclone Update is also used to provide a continuous flow of information regarding the center location of a tropical cyclone when watches or warnings are in effect and the center can be easily tracked with land-based radar. Tropical Cyclone Updates, which can be issued at any time, can be found under WMO header WTNT61-65 KNHC, and under AWIPS header MIATCUAT1-5.
All National Hurricane Center text and graphical products are available on the web at http://www.hurricanes.gov. You can also interact with NHC on Facebook at https://www.facebook.com/NWSNHC. Notifications are available via Twitter when select National Hurricane Center products are issued. Information about our Atlantic Twitter feed is available at http://www.hurricanes.gov/twitter.php.
Tomorrow kicks off the 2014 Hurricane Season. We have completely updated the website this year, which will mark our 10th year of covering storms here on Caribbean-On-Line. The site is now mobile friendly and should be much more easy to navigate and use on your phone and tablet.
Please see our new re-design of the Hurricane Blog, and remember that you can unsubscribe from these emails at any time by visiting the home page and using the small form in the left hand navigation (from a computer web browser only - you won't see that option on mobile devices at the moment!).
Last season was particularly quiet after a lot of bold predictions - we'll hope for the same in 2014! Wishing peace and safety to all of our friends in the Caribbean.