000
AXNT20 KNHC 180539
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
105 AM EST FRI JAN 18 2013

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.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL 
ATLC NEAR 6N10W TO 5N13W WHERE THE ITCZ CONTINUES ALONG 2N16W 
1N27W TO ALONG THE EQUATOR BETWEEN 30W-43W. SMALL CLUSTERS OF 
SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 75 NM 
OF LINE FROM 4N12W TO 2N29W. 

...DISCUSSION...

GULF OF MEXICO...
DEEP LAYERED TROUGH COVERS THE E CONUS TO OVER THE GULF N OF 27N 
AND INTO THE W ATLC SUPPORTING A STRONG COLD FRONT THAT EXTENDS 
AT 18/0300 UTC FROM A 1007 MB LOW OFF THE COAST OF NORTH 
CAROLINA THROUGH THE W ATLC AND THE STRAITS OF FLORIDA ALONG 
24N80W TO OVER CUBA AND INTO THE NW CARIBBEAN JUST E OF HAVANA. 
DENSE CLOUD COVER WITH SCATTERED SHOWERS ARE WITHIN 180 NM W OF 
THE FRONT S OF 25N.  COLD AIR STRATOCUMULUS CLOUDS COVER THE 
GULF S OF A LINE FROM PANAMA CITY FLORIDA TO 27N95W. SURFACE 
RIDGE HAS MOVED OVER THE GULF IN THE WAKE OF THE FRONT ANCHORED 
BY A PAIR OF 1033 MB HIGHS OVER NE TEXAS AND SE MISSOURI. COLD 
FRONT WILL MOVE E OF THE AREA TONIGHT. WINDS AND SEAS WILL 
DIMINISH FROM W TO E ACROSS THE ENTIRE GULF FRI. HIGH PRESSURE 
WILL STRENGTHEN BRIEFLY ON MON THEN RELAX SOME ON TUE AS A 
SURFACE HIGH SHIFTS SE OVER THE NE COASTAL PLAINS.

CARIBBEAN SEA...
NEAR ZONAL WESTERLY FLOW ALOFT IS ACROSS THE ENTIRE CARIBBEAN 
BASIN. THE GULF OF MEXICO/W ATLC COLD FRONT EXTENDS AT 18/0300 
UTC ACROSS CUBA JUST E OF HAVANA ALONG 20N85W TO THE GULF OF 
HONDURAS NEAR 16N88W. DENSE CLOUD COVER WITH SCATTERED SHOWERS 
ARE W OF THE FRONT TO OVER W CUBA/THE YUCATAN PENINSULA AND 
THROUGH THE YUCATAN CHANNEL. THE PRESSURE GRADIENT BETWEEN THE 
SURFACE RIDGE OVER THE W ATLC AND THE LOWER PRESSURE OVER SOUTH 
AMERICA REMAINS CREATING FRESH EASTERLY TRADE WINDS ACROSS THE 
CENTRAL CARIBBEAN. THESE TRADE WINDS ARE GENERATING CLUSTERS OF 
ISOLATED SHOWERS MAINLY S OF 20N E OF 80W. THE TRADE WINDS WILL 
PERSIST THROUGH TUE. THE COLD FRONT WILL STALL FROM CENTRAL CUBA 
TO E HONDURAS LATE FRI WITH THE REMNANTS OF THE FRONT GRADUALLY 
DISSIPATING SAT THROUGH TUE.

ATLANTIC OCEAN...
A DEEP LAYERED TROUGH THAT COVERS THE E CONUS EXTENDS OVER THE W 
ATLC N OF 27N W OF 75W SUPPORTING A COLD FRONT THAT EXTENDS AT 
18/0300 UTC FROM A 1007 MB LOW OFF THE COAST OF NORTH CAROLINA 
THROUGH 32N76W ACROSS GRAND BAHAMA ISLAND INTO THE STRAITS OF 
FLORIDA NEAR 24N80W CONTINUING INTO THE CARIBBEAN ACROSS CUBA 
JUST E OF HAVANA. SCATTERED SHOWERS ARE WITHIN 75 NM W OF THE 
FRONT. LARGE UPPER RIDGE COVERS THE REMAINDER OF THE W ATLC AND 
ALL OF THE CENTRAL ATLC ANCHORED NEAR 28N54W. A WEAK UPPER LOW 
IS IN THE SE ATLC CENTERED NEAR 20N41W. A 1015 MB SURFACE LOW IS 
ANALYZED NEAR 20N41W WITH A SURFACE TROUGH TO THE E ALONG 22N39W 
19N38W TO 13N45W. SCATTERED SHOWERS ARE FROM 18N-22N BETWEEN 
37W-42W. A BROAD SURFACE RIDGE COVERS THE ATLC E OF 70W WITH A 
WEAKNESS IN THE IMMEDIATE VICINITY OF THE ABOVE SURFACE TROUGH 
AND ANCHORED BY A 1026 MB HIGH IN THE W ATLC NEAR 32N56W AND 
1026 MB HIGH IN THE E ATLC NEAR 32N19W. THE COLD FRONT WILL 
EXTEND FROM BERMUDA TO CENTRAL CUBA ON FRI EVENING THEN STALL 
FROM 32N58W TO CENTRAL CUBA SAT. REMNANTS OF THE FRONT WILL 
RETURN NW THROUGH THE NORTHERN BAHAMAS ON SUN THEN MOVE SE AGAIN 
ON MON AND TUE.

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

$$
PAW