Flhurricane.com - Central Florida Hurricane Center - Tracking Storms since 1995Hurricanes Without the Hype! Since 1995
The Atlantic is quiet
|
Show Selection: |
| #451795 (Received by flhurricane at: 5:00 AM 21.Aug.2011) TCDAT4 TROPICAL STORM IRENE DISCUSSION NUMBER 3 NWS NATIONAL HURRICANE CENTER MIAMI FL AL092011 500 AM AST SUN AUG 21 2011 SATELLITE IMAGES AND RADAR DATA FROM GUADELOUPE INDICATE THAT IRENE HAS CHANGED LITTLE IN THE PAST 6 HOURS. THE CENTER REDEVELOPED ABOUT 60 NMI FARTHER NORTH INTO THE DEEP CONVECTION. HOWEVER...A NARROW WEDGE OF DRY AIR HAS BEEN ENTRAINED INTO THE NORTHERN AND WESTERN QUADRANTS...WHICH HAS ERODED SOME OF THE INNER CORE CONVECTION NEAR THE LOW-LEVEL CENTER. AS A RESULT...THE INITIAL INTENSITY REMAINS AT 45 KT...WHICH IS SUPPORTED BY A SATELLITE INTENSITY ESTIMATE OF T3.0/45 KT FROM TAFB. THE NEXT HURRICANE HUNTER AIRCRAFT SCHEDULED TO RECONNOITER IRENE WILL BE 1200 UTC. THE INITIAL MOTION ESTIMATE IS AN UNCERTAIN 280/18 DUE TO THE UNCERTAINTY IN THE INITIAL POSITION. 00Z UPPER-AIR DATA FROM THE NORTHERN CARIBBEAN ISLANDS AND BERMUDA INDICATE A FAIRLY STOUT DEEP-LAYER SUBTROPICAL RIDGE EXISTS TO THE NORTH AND NORTHWEST OF IRENE. THE RESULTANT MODERATE EASTERLY STEERING FLOW SHOULD KEEP THE CYCLONE MOVING IN A GENERAL WESTWARD TO WEST-NORTHWESTWARD DIRECTION FOR THE NEXT 72 HOURS OR SO. AFTER THAT...A WEAKNESS IN THE RIDGE IS EXPECTED TO DEVELOP ACROSS THE EASTERN GULF OF MEXICO...FLORIDA...AND THE EXTREME WESTERN ATLANTIC...WHICH SHOULD ALLOW IRENE TO TURN NORTHWESTWARD ACROSS HAITI AND EASTERN CUBA AND EMERGE OVER THE FLORIDA STRAITS IN ABOUT 96 HOURS. ALL OF THE MODELS ARE IN EXCELLENT AGREEMENT ON THIS DEVELOPING TRACK SCENARIO EXCEPT FOR THE UKMET AND GFDL MODELS. THOSE LATTER TWO MODELS KEEP IRENE ON A WESTERLY TRACK SOUTH OF CUBA AND THROUGH THE YUCATAN CHANNEL...DESPITE THEIR DEVELOPING A SIMILAR BREAK IN THE RIDGE AXIS OVER FLORIDA BY DAYS 4 AND 5...AND ARE CONSIDERED OUTLIERS AT THIS TIME. THE OFFICIAL FORECAST TRACK IS NORTH OF THE PREVIOUS ADVISORY TRACK MAINLY DUE TO THE MORE NORTHWARD INITIAL POSITION... AND LIES CLOSE TO THE CONSENSUS MODELS TVCN AND TVCA. THE UPPER-LEVEL ENVIRONMENT IS EXPECTED TO BE QUITE FAVORABLE FOR STRENGTHENING THROUGHOUT THE FORECAST PERIOD AS A RESULT OF LOW SHEAR AND A MID-OCEANIC TROUGH TO THE EAST ACTING AS A MASS SINK FOR THE OUTFLOW IN THE EASTERN SEMICIRCLE. HOWEVER...THE INTENSITY FORECAST IS HEAVILY DEPENDENT ON HOW MUCH INTERACTION IRENE HAS WITH THE MOUNTAINOUS TERRAIN OF HISPANIOLA AND WHAT THE INNER CORE OF THE CYCLONE BECOMES AFTER IT EMERGES OFF THE NORTHEAST COAST OF CUBA IN ABOUT 4 DAYS. ONCE OVER THE FLORIDA STRAITS...HOWEVER... IRENE WILL HAVE AT LEAST 24 HOURS OVER SOME OF THE WARMEST WATER IN THE ATLANTIC TO TAP INTO. THE OFFICIAL FORECAST REMAINS ON THE CONSERVATIVE SIDE DUE TO LAND EFFECTS AND IS CLOSE TO A BLEND OF SHIPS AND LGEM STATISTICAL INTENSITY MODELS. FORECAST POSITIONS AND MAX WINDS INIT 21/0900Z 16.4N 61.3W 45 KT 50 MPH 12H 21/1800Z 17.0N 63.7W 50 KT 60 MPH 24H 22/0600Z 17.5N 66.7W 60 KT 70 MPH 36H 22/1800Z 18.0N 69.2W 70 KT 80 MPH 48H 23/0600Z 18.6N 71.5W 50 KT 60 MPH...INLAND 72H 24/0600Z 20.3N 75.3W 50 KT 60 MPH...INLAND 96H 25/0600Z 22.8N 78.2W 60 KT 70 MPH...OVER WATER 120H 26/0600Z 26.1N 80.7W 75 KT 85 MPH...INLAND $$ FORECASTER STEWART |
