Wednesday, October 24, 2012

Hurricane Sandy a potentially historic storm for New England and/or the Maritimes












000
FXUS61 KCAR 241943
AFDCAR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CARIBOU ME
ISSUED BY NATIONAL WEATHER SERVICE GRAY ME
343 PM EDT WED OCT 24 2012....
 
......LONG TERM /FRIDAY THROUGH WEDNESDAY/...
FRIDAY WILL BE MOSTLY SUNNY AS THE HIGH CONTINUES TO DOMINATE THE
PATTERN.

FOR SATURDAY HIGH PRESSURE WILL CONTINUE TO MOVE EASTWARDS. AN
APPROACHING UPPER LEVEL TROUGH WILL BRING CLOUDS TO MAINE... WITH
A CHANCE OF SHOWERS IN THE ST JOHN VALLEY OVERNIGHT SATURDAY INTO
SUNDAY. HIGH TEMPERATURES WILL REMAIN IN THE 50S...USED A BLEND OF
GUIDANCE WITH GOOD CONCENSUS.

THE EXTENDED FORECAST STILL PROVIDES A CONSIDERABLE CHALLENGE
WITH AN OVERALL LOWER CONFIDENCE. TROPICAL STORM SANDY...
CURRENTLY LOCATED IN THE CENTRAL CARIBBEAN WILL MOVE UP THE
EASTERN SEABOARD. A BROAD TROUGH WILL DIG SOUTHWARDS INTO THE
CENTRAL PART OF NORTH AMERICA MID-WEEK.... WITH A SHORT-WAVE
DIVING THROUGH THE TROUGH ACROSS THE WESTERN UNITED STATES. THIS
WILL RESULT IN A STATIONARY FRONTAL BOUNDARY PARALLEL TO THE
APPALACHAINS BY MID-DAY SUNDAY. ... WHILE TROPICAL STORM SANDY
REMAINS OFF SHORE IN THE CAROLINAS. THE INTERACTION BETWEEN SANDY
AND THE ADVANCING TROUGH WILL DETERMINE THE EXTENT OF THE STORM
FOR NEW ENGLAND FOR MONDAY INTO TUESDAY. THE GFS KEEPS THE STORM
FURTHER OUT TO SEA BEFORE CURVING EASTWARDS INTO THE GULF OF MAINE
LATE ON TUESDAY. THE EUROPEAN HAS A BIT MORE EASTWARD PROGRESSION
IN THE STATIONARY FRONT... RESULTING IN SANDY IMPACTING SOUTHERN
NEW ENGLAND DIRECTLY EARLY TUESDAY AND THEN MOVING NORTHWARDS AS A
BROADER CIRCULATION. WHILE THERE IS STILL CONSIDERABLE VARIABILITY,
CONCENSUS IS LEANING MORE AND MORE TOWARDS THIS STORM CAUSING
SIGNIFICANT IMPACT TO MAINE. AT THIS POINT I HAVE TRENDED TOWARDS
THE CONCENSUS... WITH WIDESPREAD RAIN BEGINNING MONDAY NIGHT INTO
TUESDAY. HAVE KEPT THE WINDS A BIT LOWER THAT MOST GUIDANCE
SUGGESTS... DUE TO WIDE RANGE OF DIFFERENCES IN THE INTENSITY OF
THE SYSTEM AS IT CROSSES MAINE. COASTAL EFFECTS INCLUDING HIGH
SEAS, BEACH EROSION, AND COASTAL FLOODING ARE ALSO POSSIBLE DURING
THIS EVENT... BUT HAVE LIMITED SEAS TO BE COMMENSURATE WITH HPC WINDS
FOR THE TIME BEING.
 
000
WTNT43 KNHC 242053
TCDAT3

HURRICANE SANDY DISCUSSION NUMBER  10
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL182012
500 PM EDT WED OCT 24 2012

SATELLITE IMAGERY SHOWS THAT THE CENTER OF SANDY MADE LANDFALL OVER
SOUTHEASTERN JAMAICA AROUND 1900 UTC. THERE HAS BEEN LITTLE
DEGRADATION TO THE SATELLITE PRESENTATION SINCE LANDFALL...AND THE
INITIAL INTENSITY IS MAINTAINED AT 70 KT FOR THIS ADVISORY. THE
CENTRAL PRESSURE OF 970 MB IS SUPPORTED BY A RECENT OBSERVATION OF
972 MB AT KINGSTON WITH 38 KT OF WIND. ASIDE FROM LAND
INTERACTION...CONDITIONS APPEAR FAVORABLE FOR SANDY TO AT LEAST
MAINTAIN INTENSITY UNTIL IT MOVES ACROSS EASTERN CUBA...WHERE SOME
WEAKENING IS EXPECTED. THE HURRICANE AND GLOBAL MODELS SHOW THE
CYCLONE INTENSIFYING OVER THE BAHAMAS AS IT INTERACTS WITH AN
UPPER-LEVEL TROUGH...AND THE OFFICIAL FORECAST SHOWS SANDY
REGAINING HURRICANE INTENSITY BY 36 HOURS. AFTER THAT TIME...ONLY
A LITTLE WEAKENING IS EXPECTED AS SANDY IS MAINTAINED AS A STRONG
CYCLONE WITH AT LEAST SOME CONTRIBUTION FROM BAROCLINIC PROCESSES
THROUGH DAY 5...WHEN POST-TROPICAL STATUS IS INDICATED.

THE INITIAL MOTION ESTIMATE IS 010/12...AS SANDY IS MOVING NORTHWARD
INTO A BREAK IN THE SUBTROPICAL RIDGE. THE GUIDANCE HAS TRENDED A
LITTLE FASTER IN THE SHORT TERM AND SO HAS THE OFFICIAL FORECAST.
ON DAY 2...A TURN TOWARD THE NORTH-NORTHWEST AND A SLOWER FORWARD
SPEED ARE SHOWN AS SANDY INTERACTS WITH THE ABOVE-MENTIONED
UPPER-LEVEL TROUGH. AFTER THAT TIME...SANDY IS EXPECTED TO TURN
NORTHEASTWARD AS IT BEGINS TO INTERACT WITH A LARGER UPPER-TROUGH
MOVING INTO THE EASTERN UNITED STATES. WHILE THERE IS STILL QUITE A
BIT OF EAST/WEST SPREAD IN THE GUIDANCE AT DAYS 4 AND 5...THE GFS
HAS TRENDED TOWARD THE SCENARIO THAT HAS BEEN SHOWN BY THE ECMWF OF
MORE INTERACTION WITH THE TROUGH. WHILE THE GFS TRACK HAS SHIFTED
WESTWARD AS A RESULT...THE ECMWF HAS ALSO SHIFTED WESTWARD THIS
CYCLE. THE NHC FORECAST HAS BEEN ADJUSTED TO THE LEFT AS WELL...AND
LIES ABOUT HALFWAY BETWEEN THE ECMWF AND THE GEFS ENSEMBLE MEAN AND
THE FSU SUPER ENSEMBLE AT DAYS 3 THROUGH 5. THE UNCERTAINTY IN THE
LONG-RANGE TRACK FORECAST REMAINS VERY HIGH...AND IT IS TOO EARLY
TO DETERMINE SPECIFIC IMPACTS FOR THE U.S. EAST COAST NORTH OF
FLORIDA.

GIVEN THE NEW NHC FORECAST...A HURRICANE WARNING HAS BEEN ISSUED
FOR THE CENTRAL AND NORTHWESTERN BAHAMAS...AND A TROPICAL STORM
WARNING HAS BEEN ISSUED FOR A PORTION OF THE EAST COAST OF THE
FLORIDA PENINSULA.

FORECAST POSITIONS AND MAX WINDS

INIT  24/2100Z 18.3N  76.6W   70 KT  80 MPH
 12H  25/0600Z 20.3N  76.3W   70 KT  80 MPH...INLAND
 24H  25/1800Z 23.5N  76.3W   60 KT  70 MPH...OVER WATER
 36H  26/0600Z 25.8N  76.8W   65 KT  75 MPH
 48H  26/1800Z 27.3N  77.3W   65 KT  75 MPH
 72H  27/1800Z 30.0N  76.0W   60 KT  70 MPH
 96H  28/1800Z 33.5N  72.5W   60 KT  70 MPH
120H  29/1800Z 37.0N  70.5W   60 KT  70 MPH...POST-TROPICAL

$$
FORECASTER BRENNAN