FXCN31 CWHX 151200
TROPICAL CYCLONE TECHNICAL INFORMATION STATEMENT ISSUED BY THE 
CANADIAN HURRICANE CENTRE OF ENVIRONMENT CANADA AT 9.00 AM ADT 
THURSDAY 15 SEPTEMBER 2011.

THE NEXT STATEMENT WILL BE ISSUED BY 3.00 PM ADT

1. CURRENT POSITION, STRENGTH, CENTRAL PRESSURE AND MOTION

AT 9.00 AM ADT , TROPICAL STORM MARIA WAS LOCATED NEAR LATITUDE
31.4 N AND LONGITUDE 68.0 W , ABOUT 180 NAUTICAL MILES OR 330
KM WEST SOUTHWEST OF BERMUDA . MAXIMUM SUSTAINED WINDS ARE
ESTIMATED AT 60 KNOTS ( 111 KM/H ) AND CENTRAL PRESSURE AT 997
MB. MARIA IS MOVING NORTH NORTHEAST AT 27 KNOTS ( 50 KM/H ).

2. FORECAST POSITION, CENTRAL PRESSURE AND STRENGTH

DATE     TIME     LAT    LON   MSLP  MAX WIND
          ADT                    MB  KTS  KMH
SEP 15  9.00 AM  31.4N  68.0W   997   60  111
SEP 15  9.00 PM  36.0N  64.8W   980   65  120
SEP 16  9.00 AM  41.8N  57.8W   982   65  120 POST-TROPICAL
SEP 16  9.00 PM  47.5N  49.5W   986   60  111 POST-TROPICAL
SEP 17  9.00 AM  53.6N  42.7W   990   55  102 POST-TROPICAL

3. TECHNICAL DISCUSSION

A. ANALYSIS

SATELLITE IMAGERY INDICATES THAT MARIA IS MOVING NORTH NORTHEAST AND 
THE SURFACE PRESSURE IS SLOWLY FALLING. SATELLITE IMAGERY INDICATES 
ORGANISED CONVECTION PATTERN WITH GOOD OUTFLOW NORTH AND SOUTH.
CLOUD TOP TEMPERATURES HAVE DROPPED TO -75 TO -80 C. WHILE THERE
IS WEAK SHEAR EAST OF THE STORM AND STRONGER SHEAR WEST OF IT, THIS 
DOESN'T SEEM TO HAVE IMPEDED DEVELOPMENT. THE TRACK BRINGS MARIA
OVER SST VALUES OF 27-29C THROUGHOUT THE DAY AND THE VERTICAL
SHEAR IS NOT EXPECTED TO BE VERY STRONG FOR THIS PERIOD AS WELL.

HOWEVER A TRMM PASS AT 0506Z SHOWED THE SURFACE CIRCULATION
DISPLACED SLIGHTLY TO THE SOUTHWEST OF THE CONVECTION NEEDED TO
DRIVE IT. BUT GIVEN THE OTHER FACTORS ABOVE GIVING A FAIR CHANCE FOR 
DEVELOPMENT WE CONTINUE TO SUPPORT A FORECAST OF A CATEGORY 1 SYSTEM 
WITHIN 12-24 HOURS AT THIS TIME.

B. PROGNOSTIC

NWP CONTINUE IN GOOD AGREEMENT WITH RESPECT TO THE NORTH TO NORTHEAST 
TRACK DURING THE NEXT 24-48 HOUR PERIOD. MOST MODELS CONTINUE TO 
AGREE ON MARIA PASSING SOUTHEAST OR NEAR THE AVALON PENINSULA OF 
NEWFOUNDLAND. THE LATEST GUIDANCE IS SIMILAR TO THE PREVIOUS
FORECAST CYCLE SO THE TRACK IS ONLY SLIGHTLY TWEAKED.

WHILE MOST INTENSITY GUIDANCE INDICATES HIGH-END TROPICAL STORM 
STRENGTH WITH A FEW MODELS SUCH AS THE SHIPS SUGGEST STRENGTHENING 
INTO A MARGINAL CAT-1 HURRICANE. THIS COMBINED WITH THE EVIDENCE OF 
STRENGTHENING OBSERVED FROM LAST EVENING RECON FLIGHT AND RECENT 
SATELLITE IMAGERY GIVES ENOUGH SUPPORT TO FORECAST IT DEVELOPING
INTO A MARGINAL HURRICANE UNTIL IT MOVES NEAR CANADIAN WATERS. WHEN 
IT MOVES OVER COOLER  WATER NORTH OF THE GULF STREAM AND INTO A MORE 
SHEARED ENVIRONMENT IT WILL BECOME A STRONG TROPICAL STORM UNTIL 
BECOMING POST-TROPICAL JUST BEFORE IT ENTERS CANADIAN FORECAST 
WATERS.

WHILE THE TRACK OF MARIA MAY TAKE A MORE SOUTHEASTWARD SHIFT THE 
SPRAWLING WIND FIELD AROUND THE STORM AND ITS ASSOCIATED 
PRECIPITATION MAY SPREAD WELL TO THE NORTHWEST OF THE TRACK.
ANOTHER COMPLICATING FACTOR IS THE MERGING OF THE TROPICAL
MOISTURE ENVELOPE WITH THE APPROACHING MID-LATITUDE COLD FRONT.
IN ANY EVENT SOME MODELS SUCH AS THE GFS ARE SUGGESTING
A HEAVY RAINFALL AND WIND EVENT FOR PARTS OF NEWFOUNDLAND. ENSEMBLE 
GUIDANCE INDICATES A 40 PERCENT PROBABILITY OF A RAINFALL
EVENT EXCEEDING 50 MM ALONG THE SOUTH COAST OF NEWFOUNDLAND.

C. PREDICTED WIND RADII (NM)

TIME          GALES           STORMS            HURRICANE
         NE  SE  SW  NW    NE  SE  SW  NW    NE  SE  SW  NW
15/12Z  180 160  80  90    90  80  50  60     0   0   0   0
16/00Z  200 190  80  90   110 100  40  50    50  40  30   0
16/12Z  220 200 100  80   130 110  40  50    40  30  20   0
17/00Z  240 170 100  70   120 100  40  50     0   0   0   0
17/12Z  210 130 100  70   110  80  50  60     0   0   0   0

END/MERCER/FOGARTY/COUTURIER