000
AXPZ20 KNHC 110254
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC THU DEC 11 2008

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0230 UTC.

...ITCZ...
THE INTERTROPICAL CONVERGENCE ZONE IS ALONG THE LINE...06N77W TO 
07N105W TO 09N115W TO 07N140W. SCATTERED MODERATE WITH ISOLATED 
STRONG CONVECTION IS WITHIN 60 NM EITHER SIDE OF THE ITCZ AXIS E 
OF 89W. SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION IS 
WITHIN 150 NM OF THE POINT 11N113W.

...DISCUSSION...

DEEP LAYER TROUGH IS OVER MEXICO. THE GULF OF MEXICO COASTAL 
PLAINS OF EAST MEXICO ARE BEING AFFECTED BY A STRONG COLD FRONT 
WITH STRONG NORTHERLY WINDS AND OVERCAST COLD AIR STRATOCUMULUS. 
OTHERWISE THE AREA UNDER THE TROUGH IS DRY IN THE LOWER AND 
MIDDLE AND UPPER LEVELS AND CLOUD FREE. THE TROUGH IS EXPECTED 
TO CONTINUE THROUGH 24 HOURS THEN WEAKEN AND MOVE EAST.

A DEEP LAYER TROUGH IS OVER THE NORTHWEST PART OF THE AREA 
CENTERED NEAR 27N130W. THE NORTHEAST SEMICIRCLE OF THE 
CIRCULATION IS MOIST AND DIFLUENT ALOFT WITH A LARGE AREA OF 
MULTI LEVEL CLOUDS WITHIN 600 NM IN THE NORTHEAST SEMICIRCLE.  

A MAINLY UPPER LEVEL TROUGH IS ALONG THE LINE FROM 23N120W TO 
03N127W. THE AREA EAST OF THIS AXIS OUT TO 107W N OF 07N AND TO 
120W S OF 07N IS MOIST IN THE MIDDLE AND UPPER LEVELS WITH MULTI 
LEVEL OVERCAST CLOUDS. A LARGE AREA OF PERSISTENT CONVECTION IS 
STILL PRESENT WITHIN 150 NM OF THE POINT 11N113W. THE CONVECTION 
WHICH BEGAN ABOUT 24 HOURS AGO IS NOW BEGINNING TO DIMINISH IN 
AREAL EXTENT. A TROUGH IS ANALYZED AT THE SURFACE NEAR THE 
CONVECTION BUT NO DEVELOPMENT OF THIS FEATURE IS FORECAST.

REMAINDER OF THE MIDDLE AND UPPER LEVELS IS BROAD ANTICYCLONIC 
FLOW.

MODERATE SURFACE RIDGE IS NORTH OF 15N WEST OF 110W. REMAINDER 
OF THE AREA IS ANALYZED AS BROAD TROUGH.

GAP WINDS IN THE GULF OF TEHUANTEPEC HAVE BEGUN AND WILL RAPIDLY 
INCREASE TO GALE FORCE TONIGHT. THESE GALE CONDITION WILL 
CONTINUE THROUGH 48 HOURS THEN DIMINISH RAPIDLY AFTER 72 HOURS.
 
$$
LL