Flhurricane.com - Central Florida Hurricane Center - Tracking Storms since 1995Hurricanes Without the Hype! Since 1995
The Atlantic is quiet
|
Show Selection: |
| #458759 (Received by flhurricane at: 10:46 PM 11.Sep.2011) TCDAT4 TROPICAL STORM MARIA DISCUSSION NUMBER 22 NWS NATIONAL HURRICANE CENTER MIAMI FL AL142011 1100 PM AST SUN SEP 11 2011 WITHOUT RECON DATA OR VISIBLE SATELLITE IMAGERY...THE LOCATION OF THE CENTER OF MARIA HAS BEEN A STRUGGLE TO PINPOINT. RADAR DATA FROM SAN JUAN WERE INCONCLUSIVE...BUT A COUPLE OF MICROWAVE PASSES...CONTINUITY FROM THE PREVIOUS TRACK...AND LAST-VISIBLE SATELLITE IMAGES SUGGEST THAT THE CENTER OF MARIA REMAINS TO THE WEST OF A LARGE BLOB OF VERY COLD-TOPPED CONVECTION. OBSERVATIONS FROM THE NEARBY NOAA BUOY 41043 AND OTHER SURFACE SYNOPTIC DATA SUGGEST AN EAST-WEST ELONGATION TO THE LOW-LEVEL CENTER. DVORAK T-NUMBERS ARE 3.0 AND 3.5 FROM SAB AND TAFB AND...WITH NO APPARENT CHANGE IN THE STORM STRUCTURE SINCE THE LAST ADVISORY...THE INITIAL INTENSITY IS KEPT AT 50 KT. ALTHOUGH UNCERTAIN...RECENT FIXES YIELD A MOTION OF 300/09...MORE OR LESS. MODEL GUIDANCE SHOWS MARIA APPROACHING THE WESTERN EXTENSION OF A LOW- TO MID-LEVEL RIDGE DURING THE NEXT 36 HOURS...A SYNOPTIC PATTERN THAT SHOULD FAVOR A SLOW WEST-NORTHWESTWARD TO NORTHWESTWARD MOTION. BETWEEN 36-72 HOURS...A TROUGH IN THE SOUTHERN STREAM OVER THE SOUTHEASTERN UNITED STATES IS FORECAST TO SLIDE EASTWARD...GRADUALLY INDUCING A RECURVING TRACK NEAR 70W. A LARGER AND MORE POTENT TROUGH SWINGING THROUGH THE NORTHEASTERN STATES BY 96 HOURS SHOULD ACCELERATE MARIA NORTHEASTWARD OVER HIGHER LATITUDES. THE OFFICIAL NHC TRACK IS LARGELY UNCHANGED FROM THE PREVIOUS ONE THROUGH 36 HOURS...AND A HAIR TO THE LEFT AFTER THAT FOLLOWING THE MULTI-MODEL CONSENSUS. AS ALWAYS...THE INTENSITY FORECAST IS FAIRLY CHALLENGING. UW-CIMSS AND SHIPS SHEAR ANALYSES INDICATE MODERATE TO STRONG WESTERLY SHEAR PREVAILING OVER MARIA AS A RESULT OF A SHARP UPPER TROUGH JUST NORTHWEST OF THE CYCLONE. LARGE-SCALE MODELS SHOW LITTLE TO NO DECREASE IN THE SHEAR FOR AT LEAST 36 HOURS...WHICH MAKES THE PROSPECTS FOR SIGNIFICANT SHORT-TERM INTENSIFICATION SLIM. BETWEEN 36-72 HOURS...THERE COULD BE A MODEST REDUCTION IN THE SHEAR AS THE INFLUENCE OF THE NEARBY UPPER-LEVEL TROUGH WEAKENS. HOWEVER...MARIA IS FORECAST TO MOVE OVER OR CLOSE TO THE COLD WAKE LEFT BEHIND BY KATIA WHICH TRAVERSED THIS REGION LESS THAN A WEEK AGO. IN SPITE OF THE GENERALLY UNFAVORABLE CONDITIONS...THE REGIONAL HURRICANE MODELS SHOW SIGNIFICANT STRENGTHENING AROUND 48 HOURS. THE OFFICIAL INTENSITY FORECAST IS MORE CONSERVATIVE AND FOLLOWS THE STATISTICAL-DYNAMICAL LGEM GUIDANCE. BEYOND 72 HOURS...A SHARP INCREASE IN SOUTHWESTERLY SHEAR IS FORECAST IN ASSOCIATION WITH THE TROUGH OVER THE WESTERN ATLANTIC...WHICH SHOULD BRING ANY STRENGTHENING TO AN END. GIVEN THE ENORMOUS VERTICAL SHEAR INDICATED BY THE GLOBAL MODELS BY 96-120 HOURS...EXTRATROPICAL TRANSITION SEEMS LIKELY BY THE END OF THE FORECAST PERIOD. FORECAST POSITIONS AND MAX WINDS INIT 12/0300Z 20.2N 65.9W 50 KT 60 MPH 12H 12/1200Z 21.1N 67.0W 50 KT 60 MPH 24H 13/0000Z 22.5N 68.2W 50 KT 60 MPH 36H 13/1200Z 23.7N 69.2W 50 KT 60 MPH 48H 14/0000Z 25.5N 69.5W 55 KT 65 MPH 72H 15/0000Z 31.5N 68.2W 65 KT 75 MPH 96H 16/0000Z 40.7N 61.5W 60 KT 70 MPH 120H 17/0000Z 50.0N 48.0W 55 KT 65 MPH...POST-TROP/EXTRATROP $$ FORECASTER KIMBERLAIN |
