Tropical Storm LISA Discussion 35 11PM EDT

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Tropical Storm LISA

 

000

WTNT43 KNHC 280223

TCDAT3

TROPICAL STORM LISA DISCUSSION NUMBER 35

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL

11 PM EDT MON SEP 27 2004

 

LISA REMAINS IN A SHEARED STATE...BUT THE CYCLONE HAS MANAGED TO

KEEP GENERATING NEW CONVECTION NEAR AND TO THE NORTHEAST OF THE

TIGHT LOW-LEVEL CIRCULATION CENTER. THE INITIAL INTENSITY ESTIMATE

OF 35 KT IS BASED ON NUMEROUS 30-34 KT NON-RAINFLAGGED WIND VECTORS

NOTED IN A 27/2142Z QUIKSCAT OVERPASS. WIND SPEEDS OBVIOUSLY COULD

BE HIGHER IN THE DEEPER CONVECTION IN THE NORTHEAST QUADRANT...BUT

I HAVE OPTED TO KEEP THE INTENSITY A LITTLE LOWER DUE TO THE RAPID

FLUCTUATIONS IN THE CONVECTION IN THAT REGION. THIS LOWER INTENSITY

IS ALSO CONSISTENT WITH THE 1006 MB PRESSURE AND 34 KT WIND

ESTIMATES OBTAINED FROM A 27/2046Z AMSU OVERPASS.

 

THE INITIAL MOTION ESTIMATE IS 350/07. THE INITIAL POSITION WAS

ADJUSTED SLIGHTLY EASTWARD BASED ON AMSU OVERPASS AND QUIKSCAT

POSITION ESTIMATES. OTHER THAN THAT...THERE IS NO SIGNIFICANT

CHANGE TO THE PREVIOUS FORECAST TRACK REASONING. LISA IS EXPECTED

TO MOVE SLOWLY NORTHWARD BETWEEN A RIDGE TO THE EAST AND A WEAK

TROUGH TO THE WEST. BY 72 HOURS...A SHORTWAVE TROUGH IS FORECAST TO

APPROACH LISA FROM THE WEST AND GRADUALLY RECURVE THE CYCLONE

NORTHEASTWARD. ALL OF THE NHC MODEL GUIDANCE AGREES ON THIS

SCENARIO...AND THE TIMING OF THE NORTHEASTWARD TURN IS THE ONLY

DIFFERENCE BETWEEN THE MODELS. THE OFFICIAL FORECAST TRACK IS

SIMILAR TO THE NHC MODEL CONSENSUS.

 

LISA IS FORECAST TO REMAIN UNDER SOUTH TO SOUTHWESTERLY VERTICAL

SHEAR FOR THE NEXT 36 HOURS SO LITTLE...IF ANY...SIGNIFICANT

INTENSIFICATION IS EXPECTED DURING THAT TIME. HOWEVER...BY 48-96

HOURS...THE SHEAR IS EXPECTED TO WEAKEN TO LESS THAN 10 KT WHILE

LISA IS STILL OVER 27+ CELSIUS SSTS. THIS SHOULD ALLOW FOR SOME

STRENGTHENING TO OCCUR AND LISA COULD POSSIBLY EVEN REACH MINIMAL

HURRICANE STRENGTH BEFORE INCREASING WESTERLY SHEAR AND COOLER SSTS

INITIATE A WEAKENING TREND BY 120 HOURS.

 

FORECASTER STEWART

 

FORECAST POSITIONS AND MAX WINDS

 

INITIAL 28/0300Z 22.3N 46.4W 35 KT

12HR VT 28/1200Z 23.4N 46.6W 35 KT

24HR VT 29/0000Z 24.9N 46.9W 35 KT

36HR VT 29/1200Z 27.0N 47.2W 40 KT

48HR VT 30/0000Z 29.0N 47.3W 45 KT

72HR VT 01/0000Z 32.0N 47.8W 55 KT

96HR VT 02/0000Z 35.5N 47.0W 60 KT

120HR VT 03/0000Z 37.5N 44.5W 55 KT

 

 

$$