[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 021741
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
105 PM EST WED DEC 02 2015

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF
SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE
EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE
IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL
ANALYSIS.

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1715 UTC.

...SPECIAL FEATURES...

A GALE WARNING IS IN EFFECT FOR THE WEST-CENTRAL AND SW GULF OF
MEXICO. AT 1200 UTC...A COLD FRONT IS ANALYZED ACROSS THE GULF
AND EXTENDS FROM PENSACOLA FLORIDA TO S OF TAMPICO MEXICO.
REINFORCING COLDER AIR MOVING ACROSS EASTERN TEXAS WILL PUSH
INTO THE NW GULF ALLOWING THE FRONT TO REACH A POSITION FROM THE
FLORIDA BIG BEND TO VERACRUZ MEXICO THIS EVENING AND FROM SW
FLORIDA TO THE BAY OF CAMPECHE THU AFTERNOON. STRONG TO GALE
FORCE NORTHERLY WINDS AND BUILDING SEAS WILL FOLLOW THE FRONT
ALONG THE COAST OF MEXICO LATE TONIGHT THROUGH THU NIGHT AS
STRONG HIGH PRES BUILDS IN THE WAKE OF THE FRONT. IT IS FORECAST
TO STALL FROM SOUTH FLORIDA AND THE FLORIDA KEYS TO THE YUCATAN
CHANNEL FRI THROUGH SUN. PLEASE SEE LATEST NWS HIGH SEAS
FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/ FZNT02 KNHC FOR MORE
DETAILS.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 9N13W TO
08N17W. THE INTERTROPICAL CONVERGENCE ZONE AXIS CONTINUES FROM
08N17W TO 04N30W TO 05N45W TO 04N51W. AN AREA OF SCATTERED
MODERATE TO ISOLATED STRONG CONVECTION IS NOTED FROM 03N-07N
BETWEEN 42W-53W.

...DISCUSSION...

GULF OF MEXICO...

A VIGOROUS MIDDLE TO UPPER LEVEL LOW IS OBSERVED ON WATER VAPOR
IMAGERY OVER THE NORTH-CENTRAL CONUS WITH TROUGHING DIPPING
SOUTHWEST OVER NORTHERN TEXAS AND NW MEXICO. THE TROUGH SUPPORTS
THE AFOREMENTIONED COLD FRONT. PLEASE SEE SPECIAL FEATURES FOR
MORE DETAILS. SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING
ALONG THE FRONTAL BOUNDARY. A PRE-FRONTAL TROUGH EXTENDS FROM
31N85W TO 26N92W. MOSAIC DOPPLER RADAR FROM SE U.S. INDICATES A
BAND OF SHOWERS WITH EMBEDDED TSTMS IN ASSOCIATION WITH THIS
TROUGH AFFECTING PARTS OF THE FLORIDA PANHANDLE. SOME SHOWER
ACTIVITY IS ALSO NOTED OVER SOUTH FLORIDA UNDER THE INFLUENCE OF
A MOIST LOW LEVEL ONSHORE SE FLOW. OTHERWISE...WHILE FRESH TO
LOCALLY STRONG NORTHERLIES ARE OCCURRING NW OF THE FRONT...THE
REMAINDER OF THE GULF REGION IS UNDER THE INFLUENCE OF WEAK
RIDGING AND GENTLE TO MODERATE ANTICYCLONIC FLOW. A THERMAL
TROUGH IS MOVING WWD ACROSS THE BAY OF CAMPECHE.

CARIBBEAN SEA...

AN UPPER-LEVEL LOW PERSISTS OVER HAITI WITH A TROUGH EXTENDING
SW TO NEAR THE COSTA RICA-NICARAGUA BORDER. A RIDGE IS BEHIND
THE TROUGH AXIS AND STRETCHES FROM SE MEXICO AND WESTERN CUBA
INTO THE NW BAHAMAS. A DIFFLUENT PATTERN ALOFT BETWEEN THESE TWO
UPPER LEVEL FEATURES IS HELPING TO INDUCE AN AREA OF SHOWERS
WITH EMBEDDED TSTMS FROM 16N-20N BETWEEN 81W AND A SURFACE
TROUGH ANALYZED FROM 20N83W TO 15N84W. ISOLATED SHOWERS ARE ALSO
OCCURRING ACROSS THE CENTRAL CARIBBEAN WITHIN THE AREA OF
MAXIMUM DIFFLUENCE EAST OF THE TROUGH AXIS PRIMARILY BETWEEN 67W-
75W...INCLUDING HISPANIOLA. FARTHER EAST...ANOTHER WEAK SURFACE
TROUGH IS ANALYZED NE OF PUERTO RICO PROVIDING FOCUS FOR
ISOLATED SHOWERS ACROSS THE NE CARIBBEAN...INCLUDING PARTS OF
PUERTO RICO AND UK/US VIRGIN ISLANDS. HIGH PRES OVER THE CENTRAL
ATLC AND THE ABOVE MENTIONED TROUGH IN THE NW CARIBBEAN WILL
SUPPORT FRESH TO STRONG TRADE WINDS OVER MAINLY THE CENTRAL
CARIBBEAN THROUGH THE WEEKEND. A RECENT ASCAT PASS PROVIDED
OBSERVATIONS OF FRESH TO STRONG WINDS ACROSS THE CENTRAL
CARIBBEAN...PARTICULARLY BETWEEN HISPANIOLA AND NW VENEZUELA. AS
THE UPPER LEVEL LOW DRIFTS WESTWARD THROUGH THURSDAY...WEAK
SURFACE TROUGH AND THE ASSOCIATED PRECIPITATION IS EXPECTED
ACROSS WESTERN CUBA...THE NW CARIBBEAN AND PORTIONS OF NORTHERN
CENTRAL AMERICA. ANOTHER FACTOR FOR INCREASING RAIN PROBABILITY
WILL BE THE PRESENCE OF A STALLING COLD FRONT ACROSS SOUTH
FLORIDA...THE FLORIDA KEYS AND THE YUCATAN CHANNEL FRI THROUGH
SUN. LOCALLY HEAVY RAIN MAY OCCUR.

...HISPANIOLA...

AN UPPER LEVEL LOW IS CENTERED OVER HAITI AND CONTINUES TO
SUPPORT INCREASED CLOUDINESS AND ISOLATED SHOWERS ACROSS THE
ISLAND. THE UPPER LEVEL FEATURE WILL DRIFT WESTWARD DURING THE
NEXT 24 HOURS RESULTING IN DRIER WEATHER CONDITIONS LATE TODAY
INTO THURSDAY. MAINLY ISOLATED SHOWERS ARE EXPECTED.

ATLANTIC OCEAN...

ALOFT...A RIDGE/TROUGH/RIDGE PATTERN DOMINATES THE DISCUSSION
AREA. THE UPPER LEVEL TROUGH SUPPORTS A COLD FRONT THAT ENTERS
THE FORECAST REGION NEAR 31N31W AND EXTENDS TO NEAR 27N48W WHERE
IT BECOMES STATIONARY TO NEAR 29N58W. SCATTERED SHOWERS AND
ISOLATED TSTMS ARE OCCURRING WITHIN 120 NM EITHER SIDE OF THE
COLD FRONT. FRESH TO STRONG NORTHERLY WINDS ARE NOTED PER
SCATTEROMETER DATA BEHIND THE FRONT. OTHERWISE...A SURFACE RIDGE
INFLUENCES THE REMAINDER OF THE AREA. PRES GRADIENT BETWEEN THE
RIDGE AND LOWER PRES IN THE VICINITY OF THE ITCZ IS PRODUCING
FRESH TO LOCALLY STRONG TRADE WINDS ACROSS THE TROPICS E OF THE
LESSER ANTILLES. THE FRONT WILL CONTINUE TO MOVE SE ACROSS THE
ATLC WATERS FOLLOWED BY A STRONG HIGH PRES FORECAST TO REACH A
CENTRAL PRES OF 1037 MB BY THU MORNING. ANOTHER COLD FRONT IS
FORECAST TO MOVE OFF THE COAST OF NE FLORIDA THIS EVENING...
REACHING FROM 31N77W TO CENTRAL FLORIDA EARLY THU MORNING...AND
FROM 31N70W TO SOUTH FLORIDA LATE THU...THEN FROM 31N65W TO THE
FLORIDA KEYS ON FRI. A BAND OF SHOWERS AND TSTMS WILL BE
ASSOCIATED WITH THE FRONT.

FOR ADDITIONAL INFORMATION PLEASE VISIT
HTTP://WWW.HURRICANES.GOV/MARINE

$$
GR
This weather bulletin was brought to you by:
www.nashvilleweather.net