32 nd raiv hurricane committee bermuda country report dr. mark guishard director, bermuda weather...
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32nd RAIV Hurricane Committee
Bermuda Country Report
Dr. Mark GuishardDirector,Bermuda Weather Service
8 March 2010Fairmont Hamilton Princess
Outer rain bands
225nm
120nm
90nm
240nm
Fabian 2003
Bill 2009
Forecast accuracy
CPA: 166m West 12 am Saturday(Midnight)
Up to 70% chance of 34 knots (Tropical-
storm force winds) in the next 5 days
HURRICANE BILL - Advisory #25Issued: 12 noon Fri, Aug 21, 2009
HURRICANE BILL is a threat to Bermuda. Hurricane Watch in effect
Tropical Storm Warning in effect
Current Position: 27.6N 66.3W approx. 300 nm S of Bermuda
Recent Movement: NW or 325 degrees at 16 kt
Max Sustained Winds: 100kt gusts 120kt
Closest point of approach to Bermuda within 72 hrs:
Date: 4 am Sat, Aug 22, 2009. Distance: 182 nm to the WSW as a Cat 3
NOAA Wave buoy measurements
27.500 N 63.000 W – 306 nm SSE
1450 GMT:
Wind Direction: SEE (150 deg)
Wind Speed : 31.1 kts
Wind Gust : 38.9 kts
Wave Height : 24.3 ft (13.5 ft 24 hrs ago)
Dominant Wave Period : 12 sec
Bermuda
Bill
0.55 inches of rain recorded
0
10
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902
1/0
8/2
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9 1
2:0
0:0
0
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St Davids wind speed
St Davids wind speed max
FortProspect wind speed
FortProspect wind speed max
Comm Pt wind speed
Comm Pt wind speed max
53 Gust 84 knotsCommissioner’s Point
10-minute mean winds
Tropical Storm Force Winds Duration: ~12 hours
Max 10-minute winds at Airport: 110° 40 GUSTS 52 KTS.
Total rainfall recorded August 21st/22nd: 0.55 inches.
Lessons from Bill
• Hurricane Watch/Warning based on sea state as opposed to wind strength – BWS in-house discussion
• Lack of Emergency Alert System – SMS text message alerts from cell phone provider took too long
• Emphasis on the local conditions as opposed to the center of the Tropical System – need to de-emphasize “but it is far away!”
• Grateful to US NOAA for the buoys to the SSE & West – request they be in service for upcoming 2010 Season
• Causeway closures need to include a component of sea state
• Wave & surge forecasting lacking – Bathymetry, buoy network, tide gauges needed
Any Questions?
Dr. Mark GuishardDirector,Bermuda Weather Service
8 March 2010Fairmont Hamilton Princess