000
AXPZ20 KNHC 120343
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC THU NOV 12 2009

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 
0300 UTC.

...ITCZ...
AXIS ALONG 07N78W TO 07N114W TO 10N129W TO 07N137W TO 07N140W.  
ISOLATED MODERATE CONVECTION WITHIN 90 NM N OF AXIS E OF 84W.  
SCATTERED MODERATE TO STRONG CONVECTION WITHIN 180 NM OF AXIS 
FROM 116W-129W.

...DISCUSSION...
UPPER LEVEL ANTICYCLONE OVER PANAMA HAS RIDGE EXTEND TO 109W S 
OF 15N KEEPING VERY DRY AIR MASS UNDER IT.  BARELY ANY MOISTURE 
NOTED EXCEPT E OF 85W ALONG COASTS OF PANAMA AND COSTA RICA. 
DEEP LAYER TROUGH FROM ACROSS MEXICO TO DEVELOPING UPPER LEVEL 
CYCLONE AT 06N115W ENHANCING ITCZ CONVECTION W OF 115W AND 50 KT 
SW JET CORE ADVECTS CONVECTIVE DEBRIS NE TO WRN CENTRAL MEXICO.

SECOND ANTICYCLONE AT 17N128W HAS UPSTREAM RIDGE SQUEEZED BY 
INCOMING TROUGH QUICKLY APPROACHING 32N140W.  WEAK COLD FRONT 
ASSOCIATED WITH TROUGH EXTEND FROM 32N126W TO 27N140W LIKELY TO  
REMAIN N OF 24N AND BECOME DIFFUSE BY END OF FORECAST PERIOD. 

AT THE SURFACE...
LARGE LONG PERIOD SWELLS NOW AFFECTING BASIN GET REINFORCED BY 
LARGE AND HEALTHY SURFACE HIGH PRES CENTER BEHIND COLD FRONT AND 
CONTINUE IMPACTING E PAC MAINLY W OF 95W.  

HIGH PRES CENTER 1028 MB OVER MEXICO WEAKENS AND ALLOW WINDS 
CROSSING INTO GULF OF TEHUANTEPEC REGION TO DIMINISH BELOW GALE 
FORCE WITHIN NEXT 24 HRS.

$$
WALLY BARNES