WTCN31 CWHX 060600 CANADIAN HURRICANE INFORMATION STATEMENT ISSUED BY THE CANADIAN HURRICANE CENTRE OF ENVIRONMENT CANADA AT 3.30 AM NDT FRIDAY 06 AUGUST 2004. ...THIS IS THE FINAL CHC STATEMENT ON HURRICANE ALEX... ...ALEX NOW WELL EAST OF THE GRAND BANKS AND UNDERGOING TRANSITION TO A POST TROPICAL STORM..STILL PACKING NEAR HURRICANE-FORCE WINDS... 1. CURRENT POSITION, STRENGTH, CENTRAL PRESSURE AND MOTION AT 3.30 AM NDT... POST-TROPICAL STORM ALEX WAS LOCATED NEAR LATITUDE 46.0 N AND LONGITUDE 42.5 W... ABOUT 440 NAUTICAL MILES OR 815 KM EAST OF CAPE RACE NEWFOUNDLAND. MAXIMUM SUSTAINED WINDS ARE ESTIMATED AT 65 KNOTS... 120 KM/H... AND CENTRAL PRESSURE AT 985 MB. ALEX IS MOVING EAST AT ABOUT 45 KNOTS...83 KM/H. 2. FORECAST POSITION, CENTRAL PRESSURE AND STRENGTH DATE TIME LAT LON MSLP MAX WIND NDT MB KTS KMH AUG 06 3.30 AM 45.9 43.1W 985 65 120 POST-TROPICAL AUG 06 9.30 AM 46.8N 36.4W 990 60 111 POST-TROPICAL AUG 06 3.30 PM 47.1N 30.8W 994 55 102 POST-TROPICAL 3. PUBLIC WEATHER IMPACTS AND WARNINGS SUMMARY THE PUBLIC IS STILL ADVISED THAT RAPID VARIATIONS IN HARBOUR WATER LEVELS ARE POSSIBLE FOR THE NEXT COUPLE OF HOURS ALONG THE EASTERN COAST OF THE AVALON PENINSULA (BETWEEN CAPE RACE AND CAPE SAINT FRANCIS) AND ALONG THE EASTERN SIDE OF THE BONAVISTA PENINSULA AND POSSIBLY CONCEPTION BAY. 4. MARINE WEATHER IMPACTS AND WARNINGS SUMMARY 3 TO 5 METRE SEAS ARE PERSISTING WELL BEHIND ALEX OVER THE SOUTHEASTERN GRAND BANKS AT FORECAST TIME BUT WILL QUICKLY SUBSIDE THROUGH THE REMAINDER OF THE NIGHT. 5. TECHNICAL DISCUSSION A. ANALYSIS ALEX IS BECOMING POST-TROPICAL BUT IT STILL HAS CHARACTERISTICS MORE AKIN TO A VORTEX IN SHEAR. CONVECTION IS DIMINISHING ON THE WEST (UPSHEAR) SIDE OF THE STORM. HOWEVER..CORE CONVECTION IS NOT DIMINISHING COMPLETELY. FRONTAL FEATURES ASSOCIATED WITH ALEX APPEAR TO BE WEAKER NOW AND THERE IS NO SHORT-WAVE TROUGH INTERACTING WITH THE STORM..SO THIS IS NOT A TYPICAL CASE OF EXTRATROPICAL TRANSITION BUT MORE LIKE A CASE OF A HURRICANE SPINNING-DOWN OVER COLD WATERS. B. PROGNOSTIC ALEX IS LIKELY TO REMAIN AT LEAST A HYBRID SYSTEM (MIXTURE OF TROPICAL AND EXTRATROPICAL CHARACTERISTICS) AS IT CROSSES THE ATLANTIC AND HEADS TOWARD EUROPE. THE ECMWF MODEL SUGGESTS THAT A DEEP LOW PRESSURE SYSTEM ASSOCIATED WITH THE REMAINS OF ALEX WILL AFFECTENGLAND AT THE END OF THE WEEKEND. C. PUBLIC WEATHER SEE NOTES IN PART 3. D. MARINE WEATHER SEE NOTES IN PART 4. SPECIAL OBSERVATIONS... ALEX BECAME A RARE..HIGH LATITUDE CATEGORY-3 HURRICANE. IT WAS STILL AT MAJOR (CATEGORY-3) HURRICANE STATUS AT 42 DEGREES NORTH LATITUDE WHEN IT WAS OVER 24C WATER TEMPERATURES. ALEX QUICKLY WEAKENED AFTER MOVING OVER THE LABRADOR CURRENT WHERE WATERS WERE IN THE MID TEENS. WATER TEMPERATURES WERE RUNNING BETWEEN 2 AND 3 DEGREES ABOVE AVERAGE ALONG THE COURSE OF ALEX DURING ITS PERIOD OF UNUSUALLY STRONG INTENSITY. ALEX MOVED DIRECTLY OVER CANADIAN BUOY 44140 AROUND 22 UTC ON THURSDAY 05 AUGUST. THE SEA SEVEL PRESSURE DROPPED TO 979 MB PROVIDING AN EXCELLENT VERIFICATION OF THE HURRICANE CENTRAL PRESSURE AT THAT TIME. UNFORTUNATELY NO WIND DATA WERE AVAILABLE FROM THE BUOY. ALSO OF NOTE WAS A NEAR 6-DEGREE COOLING IN WATER TEMPERATURE AS THE HURRICANE PASSED OVER THE BUOY. SIGNIFICANT WAVE HEIGHTS REACHED 6.5 METRES AT 44140 AND 5.7 METRES AT BUOY 44138 APPROXIMATELY 60 NM NORTH OF WHERE ALEX TRACKED AND APPROXIMATELY 90 NM WEST NORTHWEST OF BUOY 44140. INTERSTINGLY..WHILE SEAS WERE SUBSIDING AT 44140 THEY WERE STILL BUILDING AT 44138 WHICH WAS FURTHER AWAY FROM THE STORM...SUGGESTING THAT THERE WERE TWO MAXIMA IN THE SEA STATE. ONE MAXIMUM WAS ASSOCIATED WITH THE HIGH WIND WAVES IN THE STORM CORE AND THE OTHER WITH THE LONG PERIOD SWELL LEFT WELL BEHIND THE STORM. WE ARE STILL AWAITING NEWS AS TO WHETHER THE EASTERN BAYS AND HARBOURS OF NEWFOUNDLAND EXPERIENCED VARIATIONS IN WATER LEVELS SUSPECTED TO HAVE FORMED IN THE WAKE OF ALEX. TIDE GAUGE DATA FROM ST. JOHNS AT BULLETIN TIME WERE INDICATING A SUDDEN DROP IN WATER LEVEL. PREDICTED WIND RADII (NM) TIME GALES STORMS HURRICANE NE SE SW NW NE SE SW NW NE SE SW NW 06/06Z 60 300 300 60 30 60 30 20 20 30 20 0 06/12Z 50 300 300 50 25 50 25 0 0 0 0 0 06/18Z 40 250 250 40 20 40 20 0 0 0 0 0 END FOGARTY