000
AXNT20 KNHC 280537
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL 
105 AM EST SUN DEC 28 2014

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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0515 UTC. 

...THE ITCZ/THE MONSOON TROUGH...                                

THE MONSOON TROUGH CROSSES THE AFRICAN COAST NEAR 6N10W AND 
EXTENDS TO 5N20W WHERE THE ITCZ BEGINS AND CONTINUES TO 4N30W TO 
TO THE COAST OF SOUTH AMERICA AT 3N51W. WIDELY SCATTERED 
MODERATE CONVECTION IS FROM 2N-9N BETWEEN 34W-45W. 

...DISCUSSION...

GULF OF MEXICO... 

A 1014 MB LOW IS CENTERED OVER CENTRAL LOUISIANA NEAR 31N93W. A 
COLD FRONT EXTENDS SW FROM THE LOW TO THE NW GULF OF MEXICO TO 
BEYOND BROWNSVILLE TEXAS AT 26N97W. 20-25 KT NORTHERLY WINDS ARE 
NW OF THE FRONT. THE REMAINDER OF THE GULF HAS 10-15 KT 
SOUTHERLY WINDS. TEMPERATURES OVER THE TEXAS COASTAL CITIES ARE 
IN THE 40'S AND 50'S. AIR TEMPERATURES OVER THE GULF WATERS SE OF 
THE FRONT ARE IN THE 70'S. RADAR IMAGERY SHOWS SCATTERED SHOWERS 
WITHIN 180 NM NW OF FRONT EXTENDING WELL INLAND. IN THE UPPER 
LEVELS...A LARGE UPPER LEVEL RIDGE WITH AXIS ALONG 80W IS 
PRODUCING SW FLOW OVER THE GULF. UPPER LEVEL MOISTURE COVERS THE 
N AND THE W GULF. EXPECT IN 24 HOURS FOR THE COLD FRONT TO 
EXTEND FROM THE FLORIDA PANHANDLE TO THE SOUTHERN BAY OF 
CAMPECHE WITH SHOWERS AND CONVECTION. 
 
CARIBBEAN SEA...   

15-25 KT TRADEWINDS ARE OVER THE CARIBBEAN WITH STRONGEST WINDS 
ALONG THE COAST OF N NICARAGUA. SCATTERED SHOWERS ARE OVER THE 
GULF OF HONDURAS...HONDURAS...AND BELIZE. MOSTLY FAIR WEATHER IS 
OVER THE REMAINDER OF THE CARIBBEAN. IN THE UPPER LEVELS... A 
LARGE UPPER LEVEL RIDGE WITH AXIS ALONG 77W IS OVER THE 
CARIBBEAN WITH STRONG SUBSIDENCE. EXPECT OVER THE NEXT 24 HOURS 
FOR SCATTERED SHOWERS TO ADVECT OVER THE WINDWARD ISLANDS...AND 
ELSEWHERE OVER THE YUCATAN PENINSULA. 
 
HISPANIOLA...                   

PRESENTLY MOSTLY FAIR WEATHER IS OVER HISPANIOLA. THE TAIL END 
OF A COLD FRONT IS JUST N OF THE ISLAND IN THE ATLANTIC. EXPECT 
OVER THE NEXT 24 HOURS FOR THE REMNANTS OF THE FRONT TO ADVECT 
OVER THE ISLAND WITH SCATTERED SHOWERS. ALOFT...RIDGING WITH 
STRONG SUBSIDENCE WILL SUPPRESS THUNDERSTORM FORMATION.   

ATLANTIC OCEAN...   

A 1026 MB HIGH IS CENTERED OVER THE W ATLANTIC NEAR 33N71W WITH 
FAIR WEATHER. A 1008 MB IS CENTERED OVER THE CENTRAL ATLANTIC 
NEAR 30N42W. A COLD FRONT EXTENDS SW FROM THE LOW TO 23N43W TO 
22N50W TO 21N60W TO 22N70W. SCATTERED SHOWERS ARE WITHIN 60 NM 
OF THE FRONT. A 1031 MB HIGH IS CENTERED OFF THE COAST OF 
PORTUGAL NEAR 37N15W WITH A SURFACE RIDGE EXTENDING S TO BEYOND 
THE CANARY ISLANDS. OF NOTE IN THE UPPER LEVELS...A LARGE UPPER 
LEVEL LOW IS CENTERED NEAR 30N40W WITH UPPER LEVEL DIFFLUENCE E 
OF THE CENTER PRODUCING ISOLATED MODERATE CONVECTION N OF 26N 
BETWEEN 24W-40W. EXPECT OVER THE NEXT 24 HOURS FOR THE COLD 
FRONT TO MOVE E WITH SHOWERS.  
 
FOR ADDITIONAL INFORMATION PLEASE VISIT 
HTTP://WWW.HURRICANES.GOV/MARINE

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FORMOSA