000
AXNT20 KNHC 161757
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
105 PM EST SUN DEC 16 2012

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.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS ACROSS AFRICA ROUGHLY ALONG 8N/9N. 
THE ITCZ EXTENDS ACROSS THE TROPICAL ATLANTIC STARTING AT THE 
COAST NEAR 8N13W TO 05N25W TO 03N40W TO THE SOUTH AMERICA NEAR  
THE EQUATOR AND 50W. NUMEROUS/SCATTERED STRONG CONVECTION IS 
LOCATED WITHIN 60 NM EITHER SIDE OF A LINE FROM 04N36W TO 02N32W 
AND FROM THE EQUATOR TO 07N BETWEEN 38W AND 45W. A SURFACE 
TROUGH IS LOCATED N OF THE ITCZ EXTENDING ALONG 51W FROM 05N TO 
13N WITH SCATTERED MODERATE/ISOLATED STRONG CONVECTION FROM 07N 
TO 10N BETWEEN 50W AND 54W. 
 
...DISCUSSION...

GULF OF MEXICO...

A MIDDLE/UPPER LEVEL ANTICYCLONIC CIRCULATION IS POSITIONED OFF 
THE PACIFIC COAST OF MEXICO NEAR 14N100W AND ALONG WITH A 
MIDDLE/UPPER LEVEL TROUGH OVER W TEXAS IS RESULTING IN MODERATE 
TO STRONG WESTERLY WINDS OVER THE ENTIRE GULF. SATELLITE DERIVED 
WINDS INDICATE THE STRONGEST WINDS N OF 28N WITH SPEEDS AS HIGH 
AS 100 KNOTS. A COLD FRONT IS LOCATED OVER E TEXAS WITH 
SCATTERED SHOWERS AND THUNDERSTORMS LOCATED ALONG MOST OF THE 
TEXAS COASTAL PLAINS. THE FRONT WILL MOVE FAIRLY RAPIDLY ACROSS 
THE GULF.


CARIBBEAN SEA...

MODERATE NORTHERLY WINDS ALOFT COVER MOST OF THE WESTERN HALF OF 
THE CARIBBEAN. LATEST WATER VAPOR IMAGERY SHOWS STRONG 
SUBSIDENCE OVER THE ENTIRE BASIN. THE SOUTHERN END OF A 
MIDDLE/UPPER LEVEL TROUGH LOCATED OVER THE W CENTRAL ATLANTIC 
COVERS THE E CARIBBEAN WITH THE AXIS RUNNING FROM PUERTO RICO TO 
12N73W. A SURFACE TROUGH IS LOCATED ALONG 74W AND IS MOVING W 10 
TO 15 KNOTS WITH SCATTERED SHOWERS WITHIN TWO TO THREE DEGREES 
EITHER SIDE OF THE AXIS.

ATLANTIC OCEAN...

OVER THE WESTERN ATLANTIC NORTHWESTERLY WINDS ALOFT HAVE SPEEDS 
IN THE 45 TO 60 KNOT RANGE. THE W CENTRAL ATLANTIC IS DOMINATED 
BY A MIDDLE/UPPER TROUGH WITH THE AXIS EXTENDING THROUGH 32N58W 
TO PUERTO RICO. THE TROUGH WILL MOVE ABOUT 20 KNOTS OVER THE 
NEXT TWO DAYS. MODERATE TO STRONG SOUTHWESTERLIES ALOFT ARE 
LOCATED UP TO 25 DEGREES E OF THE TROUGH AXIS. AT THE SURFACE A 
1012 MB LOW IS CENTERED NEAR 21N51W AND IS FORECAST TO DISSIPATE 
OVER THE NEXT 24 HOURS. A TROUGH EXTENDS N OF THE LOW TO 32N42W 
AND S OF THE LOW TO 18N53W. FURTHER S A BROAD AREA OF 
ANTICYCLONIC FLOW AT THE MIDDLE AND UPPER LEVELS IS LOCATED FROM 
08N TO NEAR 20N BETWEEN 30W AND 58W. A BROAD MIDDLE/UPPER TROUGH 
IS LOCATED OVER THE E ATLANTIC FROM 05N TO 20N E OF ABOUT 30W. A 
1030 MB HIGH IS LOCATED NEAR 33N14W WITH A RIDGE AXIS EXTENDING 
FROM THE HIGH TO 22N42W.

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

$$
CAB