000
AXPZ20 KNHC 111514
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED NOV 11 2009

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE LIES ALONG A LINE FROM 07N77W 
TO 06N105W TO 07N140W. SCATTERED MODERATE CONVECTION IS WITHIN 
THE AREA 90 NM EITHER SIDE OF THE ITCZ AXIS E OF 83W. SCATTERED 
MODERATE TO STRONG CONVECTION IS WITHIN 100 NM EITHER SIDE OF 
THE LINE FROM 11N129W TO 06N133W.

...DISCUSSION...

A MOSTLY UPPER TROUGH EXTENDS ACROSS THE AREA WITH AN AXIS FROM 
CENTRAL MEXICO NEAR 25N105W TO 10N123W. NORTH AND WEST OF THIS 
TROUGH AXIS TO A LINE FROM WEST TEXAS 20N130W TO 10N134W THE 
ATMOSPHERE IS DRY AND CLOUD FREE IN THE MIDDLE AND UPPER LEVELS. 
NORTH OF THIS DRY AREA UPPER MOISTURE IS PRESENT WITH BROKEN TO 
OVERCAST UPPER CLOUDS MAINLY WEST OF 115W. THROUGHOUT MOST OF 
THIS AREA NORTH OF THE TROUGH AXIS THE LOWER LEVELS ARE COVERED 
BY BROKEN TO OVERCAST STRATOCUMULUS CLOUDS. A DRY MIDDLE AND 
UPPER LAYER AREA IS OVER NORTHEASTERN MEXICO NORTH OF 25N E OF 
102W. A PLUME OF UPPER MOISTURE IS BEING ADVECTED NORTHEASTWARD 
FROM ITCZ CONVECTION WITHIN 100 NM EITHER SIDE OF LINE FROM 
23N100W TO 10N119W. WITHIN THIS PLUME ARE SOME THIN MOSTLY 
SCATTERED HIGH CLOUDS WITH SOME EMBEDDED CONVECTION. THE 
CONVECTION IS CONFINED TO SOUTH OF 14N.

A MOSTLY UPPER TROUGH EXTENDS FROM THE YUCATAN CHANNEL ACROSS 
NORTHERN CENTRAL AMERICA AND EASTERN MEXICO TO A CYCLONIC 
CIRCULATION CENTER NEAR 10N97W. THE AREA OVER THE OCEAN AND 
MEXICO WEST OF THE TROUGH AXIS TO THE ABOVE MENTIONED MOISTURE 
PLUME IS DRY AND CLOUD FREE IN THE MIDDLE AND UPPER LEVELS. OVER 
NORTHERN CENTRAL AMERICA SOME LOW TO MIDDLE CLOUDS WITH SOME 
EMBEDDED LOW TOPPED CONVECTION IS NOTED. MORE EXTENSIVE 
CLOUDINESS WITH SOME EMBEDDED CONVECTION IS OVER PANAMA AND 
COSTA RICA.
 
REMAINDER OF THE MIDDLE AND UPPER LEVELS IS BROAD ANTICYCLONIC 
FLOW. STRONG DEEP LAYER TROUGH IS JUST NORTHWEST OF THE AREA AND 
IS FORECAST TO MOVE ACROSS THE NORTHERN PART OF THE PACIFIC 
OCEAN AREA DURING THE NEXT SEVERAL DAYS. ASSOCIATED SURFACE COLD 
FRONT IS ALONG A LINE THROUGH 32N135W TO 29N140W. ELSEWHERE A 
MODERATE SURFACE RIDGE IS NORTH OF 15N WEST OF 110W. REMAINDER 
OF THE AREA A BROAD TROUGH IS ANALYZED AT THE SURFACE.

GALE FORCE WINDS IN THE GULF OF TEHUANTEPEC REGION ARE FORECAST 
TO PERSIST THROUGH THURSDAY.

$$
LL