000
AXNT20 KNHC 281109
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL 
705 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1045 UTC. 

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

THE MONSOON TROUGH CROSSES THE AFRICAN COAST NEAR 5N9W AND 
EXTENDS TO 5N21W WHERE THE ITCZ BEGINS AND CONTINUES TO 3N40W TO 
TO THE COAST OF SOUTH AMERICA AT 3N51W. WIDELY SCATTERED 
MODERATE CONVECTION IS FROM 1N-9N BETWEEN 32W-45W. 

...DISCUSSION...

GULF OF MEXICO... 

A 1016 MB LOW IS CENTERED OVER S MISSISSIPPI NEAR 32N90W. A COLD 
FRONT EXTENDS SW FROM THE LOW TO THE NW GULF OF MEXICO TO NE 
MEXICO AT 24N98W. 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 240 NM 
NW OF FRONT EXTENDING WELL INLAND. IN THE UPPER LEVELS...A LARGE 
UPPER LEVEL RIDGE WITH AXIS ALONG 78W 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. ISOLATED MODERATE CONVECTION IS 
OVER N BELIZE. SCATTERED SHOWERS ARE OVER THE GULF OF 
HONDURAS...AND HONDURAS. ELSEWHERE...THE TAIL END OF A COLD 
FRONT IS PRODUCING SCATTERED SHOWERS S OF 20N AND N OF THE 
VIRGIN ISLANDS...PUERTO RICO...AND HISPANIOLA. MOSTLY FAIR 
WEATHER IS OVER THE REMAINDER OF THE CARIBBEAN. IN THE UPPER 
LEVELS... A LARGE UPPER LEVEL RIDGE WITH AXIS ALONG 75W 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 1025 MB HIGH IS CENTERED OVER THE W ATLANTIC NEAR 32N68W WITH 
FAIR WEATHER. A 1007 MB IS CENTERED OVER THE CENTRAL ATLANTIC 
NEAR 30N39W. A COLD FRONT EXTENDS SW FROM THE LOW TO 26N40W TO 
20N50W TO 19N60W TO 21N71W. SCATTERED SHOWERS ARE WITHIN 60 NM 
OF THE FRONT. A 1030 MB HIGH IS CENTERED OFF THE COAST OF 
PORTUGAL NEAR 38N16W 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 30N38W WITH UPPER LEVEL DIFFLUENCE E 
OF THE CENTER PRODUCING ISOLATED MODERATE CONVECTION N OF 27N 
BETWEEN 30W-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