Caribbean-On-Line » Caribbean Hurricanes » Hurricane Bill » Bill a monster Category Four Hurricane
August 19, 2009
Bill a monster Category Four Hurricane
Hurricane Bill is a large storm, and very powerful at the moment - but the good news is that it is still tracking into relatively open waters:
A NOAA P-3 PLANE ON A RESEARCH MISSION HAS BEEN PROVIDING EXCELLENT DATA FROM BILL DURING THE PAST SEVERAL HOURS. THERE WAS A PEAK FLIGHT-LEVEL WIND OF 132 KNOTS TWO HOURS AGO AND THE SFMR REPORTED PEAK WINDS AROUND 105 KNOTS. DATA FROM THE PLANE ALSO SHOW THAT BILL HAS A LARGE WIND FIELD AND A 30 NMI WIDE EYE. THE LATEST EXTRAPOLATED MINIMUM CENTRAL PRESSURE WAS 950 MB. ALTHOUGH THE RING OF DEEP CONVECTION SURROUNDING THE EYE OBSERVED ON SATELLITE HAS WEAKENED DURING THE PAST COUPLE OF HOURS...THE T-NUMBERS REMAIN AROUND 6.0 ON THE DVORAK SCALE. INITIAL INTENSITY IS KEPT AT 115 KT IN THIS ADVISORY. THE LARGE SCALE ENVIRONMENT IS FAVORABLE FOR ADDITIONAL INTENSIFICATION SINCE BILL IS HEADING FOR A WARMER OCEAN AND THE SHEAR IS EXPECTED TO BE LOW FOR THE NEXT TWO TO THREE DAYS. HOWEVER...MOST LIKELY THERE WILL BE FLUCTUATIONS IN INTENSITY IN THIS PERIOD CONTROLLED BY EYEWALL REPLACEMENT CYCLES. BEYOND 72 HOURS...THE OCEAN IS COOLER AND A GRADUAL WEAKENING SHOULD BEGIN... BUT BILL IS FORECAST TO REMAIN A HURRICANE THROUGH FIVE DAYS.
THERE HAS BEEN NO CHANGE IN THE STEERING CURRENTS AND BILL CONTINUES TO MOVE TOWARD THE WEST-NORTHWEST OR 300 DEGREES AT 16 KNOTS AROUND THE AZORES-BERMUDA HIGH. THIS GENERAL MOTION SHOULD CONTINUE FOR A COUPLE OF DAYS. THEREAFTER...A LARGE MID-LATITUDE TROUGH IS EXPECTED TO SWING EASTWARD OVER THE EASTERN UNITED STATES...FORCING BILL TO TURN NORTHWARD A GOOD DISTANCE AWAY FROM THE U.S. EAST COAST. THIS IS IN AGREEMENT WITH THE SOLUTION PROVIDED BY MOST OF THE DYNAMICAL MODELS...WHICH IN FACT HAVE BEEN QUITE CONSISTENT IN TURNING BILL NORTHWARD FOR THE PAST SEVERAL RUNS. THE OFFICIAL FORECAST IS VERY SIMILAR TO THE PREVIOUS ONE AND IS VERY CLOSE TO THE MODEL CONSENSUS.
BECAUSE BILL IS A LARGE AND STRONG HURRICANE...SWELLS TRIGGERED BY THE HURRICANE SHOULD AFFECT THE NORTHERN LEEWARD ISLANDS...BERMUDA AND PORTIONS OF THE EASTERN UNITED STATES DURING THE NEXT FEW DAYS.
