Hurricane Leslie a potential long range threat to the region update seven

000
WTNT32 KNHC 060240
TCPAT2

BULLETIN
HURRICANE LESLIE ADVISORY NUMBER  27
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL122012
1100 PM AST WED SEP 05 2012

...LESLIE EXPECTED TO CONTINUE DRIFTING NORTHWARD THROUGH FRIDAY...


SUMMARY OF 1100 PM AST...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...26.2N 62.5W
ABOUT 445 MI...715 KM SSE OF BERMUDA
MAXIMUM SUSTAINED WINDS...75 MPH...120 KM/H
PRESENT MOVEMENT...N OR 10 DEGREES AT 2 MPH...4 KM/H
MINIMUM CENTRAL PRESSURE...985 MB...29.09 INCHES


WATCHES AND WARNINGS
--------------------
THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.

INTERESTS IN BERMUDA SHOULD MONITOR THE PROGRESS OF LESLIE.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 1100 PM AST...0300 UTC...THE CENTER OF HURRICANE LESLIE WAS
LOCATED NEAR LATITUDE 26.2 NORTH...LONGITUDE 62.5 WEST.  LESLIE IS
MOVING TOWARD THE NORTH NEAR 2 MPH...4 KM/H.  A NORTHWARD OR NORTH-
NORTHWESTWARD DRIFT IS EXPECTED THROUGH FRIDAY.

MAXIMUM SUSTAINED WINDS REAMIN NEAR 75 MPH...120 KM/H...WITH HIGHER
GUSTS.  LESLIE IS A CATEGORY ONE HURRICANE ON THE SAFFIR-SIMPSON
HURRICANE WIND SCALE.  GRADUAL STRENGTHENING IS FORECAST DURING THE
NEXT 48 HOURS.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 25 MILES...35 KM...FROM
THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 195
MILES...315 KM.  NOAA BUOY 41049 TO THE NORTHWEST OF LESLIE RECENTLY
REPORTED A 1-MINUTE SUSTAINED WIND OF 47 MPH...76 KM/H.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 985 MB...29.09 INCHES.


HAZARDS AFFECTING LAND
----------------------
SURF...SWELLS GENERATED BY LESLIE WILL CONTINUE TO AFFECT BERMUDA...
THE U.S. EAST COAST FROM CENTRAL FLORIDA NORTHWARD...THE NORTHERN
LEEWARD ISLANDS...PUERTO RICO...AND THE VIRGIN ISLANDS FOR THE NEXT
SEVERAL DAYS. THESE SWELLS COULD CAUSE LIFE-THREATENING SURF AND
RIP CURRENT CONDITIONS. PLEASE CONSULT PRODUCTS FROM YOUR LOCAL
WEATHER OFFICE FOR MORE INFORMATION.


NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...500 AM AST.

$$
FORECASTER BERG
000
WTNT42 KNHC 060240
TCDAT2

HURRICANE LESLIE DISCUSSION NUMBER  27
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL122012
1100 PM AST WED SEP 05 2012

RECENT TRMM AND SSMI MICROWAVE IMAGES INDICATE THAT LESLIE HAS NOT
FORMED A CLOSED EYEWALL...AND IN FACT...THE INNER CORE CONVECTION
HAS BECOME SOMEWHAT RAGGED.  THERE IS STILL SOME INDICATION OF
WESTERLY SHEAR AS WELL...WITH MOST OF THE CONVECTIVE BANDING
LOCATED OVER THE EASTERN SEMICIRCLE.  THE INITIAL INTENSITY IS
BEING HELD AT 65 KT BASED ON DVORAK ESTIMATES OF T4.0 FROM TAFB AND
SAB...AND A UW-CIMSS ADT ESTIMATE OF T3.7/4.3.

BASED ON RECENT TRMM MICROWAVE FIXES...THE MOTION IS ESTIMATED TO BE
010/2 KT.  LESLIE SHOULD CONTINUE A SLOW NORTHWARD CREEP FOR THE
NEXT 48 HOURS OR SO WHILE IT REMAINS TRAPPED TO THE SOUTH OF A
MID-LEVEL HIGH CENTERED TO THE NORTHEAST OF BERMUDA.  THE HURRICANE
SHOULD GAIN SOME NORTHWARD MOMENTUM BY DAY 3 ONCE A DEEP-LAYER
TROUGH DEVELOPS OVER THE EASTERN UNITED STATES.  THE GFS MODEL HAS
SHIFTED BACK TO THE EAST ON THIS CYCLE AND IS THE EASTERNMOST AND
SLOWEST OF THE DYNAMICAL GUIDANCE ON DAYS 3 THROUGH 5.  SINCE THIS
HAS NOT YET TURNED INTO A CONSISTENT TREND...THE NHC FORECAST IS
BEING KEPT CLOSER TO THE MIDDLE OF THE GUIDANCE ENVELOPE AND IS
VERY SIMILAR TO THE PREVIOUS TRACK FORECAST.

LESLIE IS PRECARIOUSLY CLOSE TO DRY AIR LOCATED OVER THE WESTERN
ATLANTIC.  A CROSS SECTION BASED ON GFS MODEL DATA SHOWS AIR WITH
RELATIVE HUMIDITY LESS THAN 30 PERCENT ABUTTING AGAINST THE
CIRCULATION IN THE 250-500 MB LAYER.  SINCE MODERATE WESTERLY SHEAR
IS EXPECTED TO AFFECT LESLIE FOR THE NEXT 24 HOURS OR SO...THE DRY
AIR COULD CONTINUE TO SEEP INTO THE CIRCULATION.  IN ADDITION...
MICROWAVE DATA INDICATES THAT THE SEA SURFACE BENEATH LESLIE IS
COOLING DUE TO UPWELLING...AND THIS IS UNLIKELY TO CHANGE AS LONG
AS THE HURRICANE MOVES SO SLOWLY.  THE NHC INTENSITY FORECAST IS
MOSTLY UNCHANGED FROM THE PREVIOUS ONE AND INDICATES GRADUAL
STRENGTHENING DURING THE NEXT 3 TO 4 DAYS. 

LESLIE IS A LARGE TROPICAL CYCLONE THAT IS FORECAST TO GROW IN SIZE
OVER THE NEXT SEVERAL DAYS. THE WIND FIELD OF THE CYCLONE...
COMBINED WITH ITS EXPECTED SLOW MOTION...WILL HELP TO GENERATE
LONG-PERIOD SWELLS THAT WILL PRODUCE LARGE WAVES AND LIFE-
THREATENING RIP CURRENTS ON BERMUDA AND MUCH OF THE U.S. EAST COAST
FOR THE REMAINDER OF THIS WEEK.

FORECAST POSITIONS AND MAX WINDS

INIT  06/0300Z 26.2N  62.5W   65 KT  75 MPH
12H  06/1200Z 26.4N  62.6W   70 KT  80 MPH
24H  07/0000Z 26.8N  62.7W   75 KT  85 MPH
36H  07/1200Z 27.1N  63.0W   80 KT  90 MPH
48H  08/0000Z 27.7N  63.4W   85 KT 100 MPH
72H  09/0000Z 30.5N  64.0W   90 KT 105 MPH
96H  10/0000Z 35.5N  63.0W   90 KT 105 MPH
120H  11/0000Z 44.0N  59.5W   75 KT  85 MPH

$$
FORECASTER BERG