000
AXNT20 KNHC 132345
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
705 PM EST SUN DEC 13 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2315 UTC.

...ITCZ/MONSOON TROUGH...
                                   
THE MONSOON TROUGH EXTENDS ACROSS W AFRICA INTO THE E TROPICAL
ATLC NEAR 7N12W TO 6N14W WHERE THE ITCZ BEGINS AND CONTINUES
ALONG 4N24W 5N42W INTO SOUTH AMERICA NEAR 3N51W. CLUSTERS OF
SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 2N-8N
BETWEEN 23W-32W. CLUSTERS OF ISOLATED MODERATE CONVECTION ARE 3N-
8N BETWEEN 32W-40W. 

...DISCUSSION...

GULF OF MEXICO...                                       
SHARP NARROW UPPER RIDGE EXTENDS FROM THE E PACIFIC ACROSS
MEXICO AND THE E GULF TO OVER THE E CONUS AND THE W ATLC NEAR NE
FLORIDA. THE BROAD SURFACE RIDGE EXTENDING FROM A 1024 MB HIGH
IN THE W ATLC IS RETREATING AS A COLD FRONT MOVES FURTHER INTO
THE GULF WATERS. AN UPPER TROUGH IS MOVING ACROSS TEXAS
SUPPORTING A COLD FRONT THAT AT 13/2100 UTC ENTERS THE W GULF
JUST W OF VERMILION BAY LOUISIANA TO OVER MEXICO NEAR LAGUNA
MADRE. NUMEROUS SHOWERS ARE WITHIN 120 NM W OF THE FRONT N OF
26N WITH SCATTERED SHOWERS OVER THE REMAINDER OF THE AREA W OF
THE FRONT TO OVER TEXAS. A WEAK SURFACE TROUGH IS MOVING INLAND
OVER THE FLORIDA E COAST FROM WEST PALM BEACH TO MIAMI BRINGING
ISOLATED SHOWERS FROM 24N-26N E OF 86W TO OVER FLORIDA AND THE
FLORIDA KEYS. THE UPPER RIDGE IS ADVECTING UPPER LEVEL MOISTURE
ACROSS THE REMAINDER OF THE GULF. ALTHOUGH STRONG SUBSIDENCE AND
DRY STABLE AIR COVER THE GULF E OF UPPER RIDGE AXIS UPPER LEVEL
CLOUDS ARE FOUND ACROSS THE REMAINDER OF THE GULF THIS EVENING.
THE FRONT WILL REACH FROM THE MOUTH OF THE MISSISSIPPI TO
VERACRUZ MEXICO LATE TONIGHT THEN WEAKEN AND BECOME STATIONARY
FROM THE FLORIDA PANHANDLE TO BAY OF CAMPECHE MON.

CARIBBEAN SEA...                                             
AN UPPER LOW IS ALONG THE NE COAST OF CUBA EXTENDING AN UPPER
TROUGH S TO CENTRAL PANAMA DOMINATING THE CARIBBEAN. SCATTERED
SHOWERS/ISOLATED THUNDERSTORMS ARE N OF 18N BETWEEN 71W-81W
INCLUDING HISPANIOLA AND E CUBA. STRONG SUBSIDENCE AND DRY
STABLE AIR COVER THE REMAINDER OF THE CARIBBEAN GIVING THE
REMAINDER OF THE BASIN FAIR WEATHER THIS EVENING. THE PRESSURE
GRADIENT BETWEEN THE W ATLC HIGH AND THE LOWER PRESSURE OVER
SOUTH AMERICA WILL CONTINUE PRODUCE FRESH TO STRONG TRADE WINDS
ACROSS THE S/CENTRAL CARIBBEAN THROUGH MON MORNING. OTHERWISE
LITTLE CHANGE IS EXPECTED. 

...HISPANIOLA...                                       
THE UPPER LOW OVER E CUBA IS GIVING THE ISLAND W OF 71W
SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS. THE UPPER
LOW/TROUGH WILL PERSIST THROUGH TUE NIGHT BEFORE SHIFTING E OVER
THE ISLAND WED. THIS WILL KEEP MOISTURE HIGH THROUGH THE TUE
BRINGING SHOWERS AND POSSIBLE THUNDERSTORMS TO THE ISLAND. 

ATLANTIC OCEAN...                                          
A SURFACE TROUGH EXTENDS FROM 28N80W INLAND OVER THE FLORIDA
PENINSULA ALONG 26N80.5W TO 25N80W GENERATING SCATTERED SHOWERS
FROM 24N-30N W OF 78W TO OVER FLORIDA. THE UPPER RIDGE OVER THE
GULF OF MEXICO EXTENDS ACROSS NE FLORIDA TO ALONG THE COAST OF
NORTH CAROLINA COVER THE NW ATLC AND INTO THE E CONUS. THE
SURFACE RIDGE IS ANCHORED OFF THE COAST OF THE CAROLINAS AND
EXTENDS A RIDGE AXIS SW TO OVER THE E GULF OF MEXICO. AN UPPER
LOW IS TO THE S OF THE UPPER RIDGE ALONG THE NE COAST OF CUBA
NEAR 21N75W GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS
S OF 24N TO OVER HISPANIOLA AND CUBA BETWEEN 70W-75W. A BROAD
UPPER TROUGH OVER THE CENTRAL ATLC IS SUPPORTING A COLD FRONT
THAT ENTERS THE REGION NEAR 32N32W ALONG 24N40W TO 23N57W WHERE
IT BECOMES STATIONARY TO 26N73W. ISOLATED TO SCATTERED SHOWERS
ARE WITHIN 75 NM SE OF THE COLD FRONT AND WITHIN 60 NM EITHER
SIDE OF THE STATIONARY FRONT. THE REMAINDER OF THE E ATLC IS
DOMINATED BY A SURFACE RIDGE THAT EXTENDS ACROSS THE CANARY
ISLANDS TO A 1018 MB HIGH NEAR 25N22W. THE CENTRAL ATLC COLD
FRONT WILL CONTINUE E AS THE STATIONARY FRONT CONTINUES TO
WEAKEN. A WEAK COLD FRONT WILL MOVE INTO THE W ATLC MON NIGHT
AND WILL STALL OUT NEAR THE FL/GA COASTS. THE FRONT WILL THEN
RETREAT NORTH AS A WARM FRONT TUE NIGHT.

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

$$
PAW