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Hurricane KATIA (Text)

ZCZC MIATCDAT2 ALL
TTAA00 KNHC DDHHMM CCA
 
HURRICANE KATIA DISCUSSION NUMBER  49...CORRECTED
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL122011
500 AM AST SAT SEP 10 2011
 
CORRECTED STATUS IN TABLE AT 12-HOUR FORECAST TIME

KATIA APPEARS TO BE GRADUALLY LOSING ITS TROPICAL CHARACTERISTICS.
THE ASSOCIATED CLOUD PATTERN IS BECOMING INCREASINGLY ELONGATED...
WITH THE LOW-LEVEL CENTER ON THE SOUTHERN EDGE OF THE 
CONVECTION. THE LATEST SATELLITE CLASSIFICATIONS SUGGEST THAT KATIA
HAS WEAKENED A LITTLE...AND THAT IS THE BASIS FOR THE SLIGHTLY
LOWER INITIAL INTENSITY OF 70 KT. STRONG SOUTHWESTERLY SHEAR
ASSOCIATED WITH A DEEP-LAYER TROUGH AND SEA SURFACE TEMPERATURES
COLDER THAN 20C...SHOULD CAUSE KATIA TO BECOME EXTRATROPICAL IN
ABOUT 12 HOURS. HOWEVER...THE CYCLONE IS EXPECTED TO REMAIN QUITE
STRONG AS AN EXTRATROPICAL SYSTEM WHILE MOVING QUICKLY ACROSS THE
FAR NORTH ATLANTIC....APPROACHING THE BRITISH ISLES AND NORTHERN
EUROPE IN A COUPLE OF DAYS.
  
THE HURRICANE IS EMBEDDED IN THE STRONG MID-LATITUDE WESTERLIES...
AND THE LATEST INITIAL MOTION ESTIMATE IS 060/38. THE CYCLONE IS
EXPECTED TO ACCELERATE DURING THE NEXT 12 TO 24 HOURS WITHIN THE
STRONG FLOW TO THE EAST OF A HIGH LATITUDE DEEP-LAYER TROUGH. THE
FORECAST TRACK IS SIMILAR TO THE PREVIOUS ONE AND CLOSE TO THE
GUIDANCE PROVIDED BY THE OCEAN PREDICTION CENTER.
 
INTERESTS IN AND AROUND THE BRITISH ISLES AND NORTHERN EUROPE SHOULD
MONITOR PRODUCTS ISSUED BY THE UKMET OFFICE AT
WWW.METOFFICE.GOV.UK/WEATHER
 
NO 96-HOUR FORECAST POINT HAS BEEN PROVIDED DUE TO SOFTWARE
ISSUES WHEN SYSTEMS MOVE EAST OF ZERO DEGREES LONGITUDE. THE 34- AND
50-KT WIND RADII WERE EXPANDED OUTWARD OVER THE WESTERN SEMICIRCLE
BASED ON A 0144 UTC ASCAT PASS.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  10/0900Z 43.3N  53.4W   70 KT  80 MPH
 12H  10/1800Z 46.0N  44.7W   65 KT  75 MPH...POST-TROP/EXTRATROP
 24H  11/0600Z 50.2N  32.2W   65 KT  75 MPH...POST-TROP/EXTRATROP
 36H  11/1800Z 53.9N  21.6W   65 KT  75 MPH...POST-TROP/EXTRATROP
 48H  12/0600Z 57.3N  13.7W   60 KT  70 MPH...POST-TROP/EXTRATROP
 72H  13/0600Z 61.3N   1.3W   45 KT  50 MPH...POST-TROP/EXTRATROP
 96H  14/0600Z...EAST OF ZERO DEGREES LONGITUDE
 
$$
FORECASTER CANGIALOSI
 
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