0300Z Tropical Update

Hurricane Bill

A Hurricane Watch and a Tropical Storm Warning is in effect for Bermuda. A hurricane watch means that hurricane conditions are possible...generally in 36 hours and a tropical storm warning means that tropical storm warning is expected...generally in 12 to 24 hours.

At 11:00 PM EDT (0300Z)...the eye of Hurricane Bill is located near 24.7 N 63.8 W. Maximum sustained winds are near 130 mph winds...this makes Bill and dangerous category 3 hurricane on the Saffir-Simpson Scale. Some strengthening is possible in the short term...but weakening will begin by Sunday morning. Movement is to the northwest at 18 mph...this motion is expected to continue with a gradual motion to the north-northwest on Friday. Estimated minimum central pressure is 944 mb/27.88 in.

Bill continues to show signs of organization during the past 6 hours and have again increased winds to 115 kts...and nearing category 4 strength. While my intensity forecast have not shown much change in strength...any increase in intensity will make Bill a category 4 again. But overall...with increasing southwest shear and cooler water temperatures...Bill will begin to weaken after 48 hours and will begin to become extratropical in about 4 days and become fully extratropical by day 5.

Initial motion 310/16 kts. Bill is gradually getting under the influence of both a subtropical ridge and the first of two troughs moving off the East Coast. The first one will cause Bill to move to the north-northwest and then to the north. A second and stronger trough will kick Bill to the northeast and east-northeast by days 4 and 5. I have moved my forecast track back to the east closer to Bermuda and should remain about 200 miles off the island...but close enough for tropical storm force winds by late Friday and into Saturday. Areas along the East Coast can expect higher than normal seas and some coastal flooding...so stay out of the water through the weekend and Bermuda continue to monitor the progress of Bill.

Forecast Positions and Intensity:

21/03Z 24.7 N 63.8 W 115 kts

21/15Z 26.5 N 66.3 W 115 kts

22/03Z 28.9 N 68.4 W 115 kts

22/15Z 31.5 N 69.6 W 115 kts

23/03Z 34.8 N 69.2 W 110 kts

24/03Z 41.5 N 63.5 W 90 kts

25/03Z 44.0 N 48.5 W 55 kts...becoming extratropical

26/03Z 45.0 N 30.0 W 35 kts...extratropical

Byron Jackson
Tropical Specialist