| 5 Day forecast track: http://www.nhc.noaa.gov/refresh/graphics_at1+shtml/084116.shtml?3-daynl?large#contents ----------------------------- HURRICANE IGOR DISCUSSION NUMBER 49 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010 500 AM AST MON SEP 20 2010 DEEP CONVECTION HAS BEEN SPUTTERING NEAR THE CENTER OF IGOR OVER THE PAST FEW HOURS...HOWEVER SATELLITE CLASSIFICATIONS AND EARLIER SURFACE OBSERVATIONS FROM BERMUDA SUPPORT KEEPING IGOR AT HURRICANE INTENSITY. LITTLE CHANGE IN STRENGTH IS EXPECTED BEFORE IGOR UNDERGOES EXTRATROPICAL TRANSITION...WHICH SHOULD BE COMPLETE BY 36 HOURS WHEN GLOBAL MODEL FIELDS SHOW THE CYCLONE BECOMING FULLY EMBEDDED WITHIN A BAROCLINIC ZONE. POST-TROPICAL IGOR IS EXPECTED TO REMAIN A STRONG EXTRATROPICAL CYCLONE FOR A DAY OR TWO BEFORE WEAKENING LATE IN THE PERIOD. THE LATEST SATELLITE FIXES SUGGEST THAT THE FORWARD MOTION OF IGOR HAS INCREASED...AND THE INITIAL MOTION ESTIMATE IS 025/17. IGOR WILL CONTINUE TO ACCELERATE TOWARD THE NORTHEAST AS IT RECURVES AHEAD OF A MID-LATITUDE TROUGH OVER THE CANADIAN MARITIMES DURING THE NEXT COUPLE OF DAYS. BY DAYS 3 AND 4 IGOR WILL TURN NORTHWARD AND THEN NORTHWESTWARD AS IT INTERACTS WITH AN UPPER-LEVEL LOW MOVING EASTWARD FROM NORTHERN QUEBEC INTO THE DAVIS STRAIT. THE GLOBAL MODEL GUIDANCE SHOWS A FASTER FORWARD SPEED IN THE FIRST COUPLE OF DAYS...AND THE OFFICIAL FORECAST HAS BEEN ADJUSTED IN THAT DIRECTION AND LIES ON THE LEFT SIDE OF THE GUIDANCE SUITE...BUT TO THE RIGHT OF THE GFS. FROM 48 HOURS ONWARD...THE NEW FORECAST IS A BLEND OF THE PREVIOUS NHC FORECAST AND THE GFS ENSEMBLE MEAN. HOWEVER...MODEL SPREAD IS QUITE LARGE AT THE END OF THE PERIOD DUE TO DIFFERENCES IN HOW IGOR INTERACTS WITH THE UPPER LOW...AND CONFIDENCE IN TRACK FORECAST NEAR THE END OF THE PERIOD IS LOW. TROPICAL STORM CONDITIONS ARE STILL BEING FELT ON BERMUDA...BUT SHOULD GRADUALLY DIMINISH TODAY. STRONG WINDS ARE POSSIBLE ALONG THE COAST OF NEWFOUNDLAND AS IGOR PASSES BY...AND THE CANADIAN HURRICANE CENTRE HAS ISSUED A TROPICAL STORM WATCH FOR A PORTION OF THAT PROVINCE. FORECAST POSITIONS AND MAX WINDS INITIAL 20/0900Z 34.2N 64.4W 65 KT 12HR VT 20/1800Z 36.7N 62.4W 65 KT 24HR VT 21/0600Z 40.6N 57.6W 65 KT 36HR VT 21/1800Z 45.6N 50.8W 70 KT...POST-TROP/EXTRATROP 48HR VT 22/0600Z 47.7N 44.5W 65 KT...POST-TROP/EXTRATROP 72HR VT 23/0600Z 55.0N 37.0W 55 KT...POST-TROP/EXTRATROP 96HR VT 24/0600Z 61.0N 41.0W 35 KT...POST-TROP/EXTRATROP 120HR VT 25/0600Z...DISSIPATED $$ FORECASTER BRENNAN ----------------------------- HURRICANE IGOR ADVISORY NUMBER 49 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010 500 AM AST MON SEP 20 2010 ...LARGE IGOR STILL BRINGING TROPICAL STORM CONDITIONS TO BERMUDA...TROPICAL STORM WATCH ISSUED FOR NEWFOUNDLAND... SUMMARY OF 500 AM AST...0900 UTC...INFORMATION ---------------------------------------------- LOCATION...34.2N 64.4W ABOUT 135 MI...215 KM N OF BERMUDA ABOUT 1045 MI...1685 KM SW OF CAPE RACE NEWFOUNDLAND MAXIMUM SUSTAINED WINDS...75 MPH...120 KM/HR PRESENT MOVEMENT...NNE OR 25 DEGREES AT 20 MPH...32 KM/HR MINIMUM CENTRAL PRESSURE...957 MB...28.26 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY... THE CANADIAN HURRICANE CENTRE HAS ISSUED A TROPICAL STORM WATCH FOR THE COAST OF NEWFOUNDLAND FROM STONES COVE EASTWARD AND NORTHWARD TO JONES HARBOUR. THE BERMUDA WEATHER SERVICE HAS CHANGED THE HURRICANE WARNING FOR BERMUDA TO A TROPICAL STORM WARNING. SUMMARY OF WATCHES AND WARNINGS IN EFFECT... A TROPICAL STORM WARNING IS IN EFFECT FOR... * BERMUDA A TROPICAL STORM WATCH IS IN EFFECT FOR... * THE COAST OF NEWFOUNDLAND FROM STONES COVE NORTHWARD AND WESTWARD TO JONES HARBOUR A TROPICAL STORM WATCH MEANS THAT TROPICAL STORM CONDITIONS ARE POSSIBLE WITHIN THE WATCH AREA...GENERALLY WITHIN 48 HOURS. FOR STORM INFORMATION SPECIFIC TO YOUR AREA...PLEASE MONITOR PRODUCTS ISSUED BY YOUR NATIONAL METEOROLOGICAL SERVICE. DISCUSSION AND 48-HOUR OUTLOOK ------------------------------ AT 500 AM AST...0900 UTC...THE CENTER OF HURRICANE IGOR WAS LOCATED NEAR LATITUDE 34.2 NORTH...LONGITUDE 64.4 WEST. IGOR IS MOVING TOWARD THE NORTH-NORTHEAST NEAR 20 MPH...32 KM/HR. A TURN TOWARD THE NORTHEAST AND AN INCREASE IN FORWARD SPEED ARE EXPECTED IN THE NEXT 24 TO 36 HOURS. ON THE FORECAST TRACK...IGOR WILL CONTINUE MOVING AWAY FROM BERMUDA AND PASS OFFSHORE OF THE SOUTHEASTERN TIP OF NEWFOUNDLAND ON TUESDAY. MAXIMUM SUSTAINED WINDS REMAIN NEAR 75 MPH...120 KM/HR...WITH HIGHER GUSTS. IGOR IS A CATEGORY ONE HURRICANE ON THE SAFFIR-SIMPSON HURRICANE WIND SCALE. LITTLE CHANGE IN STRENGTH IS FORECAST DURING THE NEXT 48 HOURS...AND IGOR IS EXPECTED TO BECOME A STRONG EXTRATROPICAL CYCLONE IN THE NEXT DAY OR TWO. IGOR IS A LARGE HURRICANE. HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 90 MILES...150 KM...FROM THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 345 MILES...555 KM. BERMUDA RECENTLY REPORTED A 10-MINUTE WIND OF 51 MPH...81 KM/HR...AND A GUST TO 62 MPH...100 KM/HR. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 957 MB...28.26 INCHES. HAZARDS AFFECTING LAND ---------------------- WIND...TROPICAL STORM CONDITIONS ARE STILL OCCURRING IN BERMUDA. THESE WINDS WILL GRADUALLY DIMINISH LATER TODAY. RAINFALL...SIGNIFICANT RAINFALL ASSOCIATED WITH IGOR IN BERMUDA HAS ENDED. STORM SURGE...A DANGEROUS STORM SURGE IS EXPECTED TO PRODUCE SIGNIFICANT COASTAL FLOODING ON BERMUDA. THE SURGE WILL BE ACCOMPANIED BY LARGE AND DESTRUCTIVE WAVES...ESPECIALLY ALONG THE SOUTHERN COAST. SURF...LARGE SWELLS WILL CONTINUE TO AFFECT THE EAST COAST OF THE UNITED STATES THROUGH TUESDAY. LARGE SWELLS WILL GRADUALLY SUBSIDE IN PUERTO RICO...THE VIRGIN ISLANDS...HISPANIOLA...AND PORTIONS OF THE BAHAMAS DURING THE NEXT COUPLE OF DAYS. THESE SWELLS ARE LIKELY TO CAUSE LIFE-THREATENING SURF AND RIP CURRENTS. PLEASE CONSULT PRODUCTS FROM YOUR LOCAL WEATHER OFFICE FOR ADDITIONAL INFORMATION. NEXT ADVISORY ------------- NEXT INTERMEDIATE ADVISORY...800 AM AST. NEXT COMPLETE ADVISORY...1100 AM AST. $$ FORECASTER BRENNAN |