000
AXPZ20 KNHC 202211
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON APR 20 2009

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

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS LIES ALONG 06N77W TO 
05N95W TO 09N113W TO 05N130W TO 06N140W. SCATTERED MODERATE TO 
ISOLATED STRONG CONVECTION IS FROM 08N TO 11N BETWEEN 110W AND 
117W. 

...DISCUSSION...
A 1026 MB HIGH IS LOCATED OFF THE COAST OF OREGON NEAR 43N130W. 
THIS HIGH IS WELL N OF THE AREA AND IS LESSENING THE SURFACE 
GRADIENT AND SURFACE WINDS W OF BAJA CALIFORNIA. PRECIPITATION 
IS WELL SOUTH CONFINED TO NEAR THE ITCZ. GFS MODEL PRECIPITATION 
POTENTIAL FORECASTS SHOWERS AND THUNDERSTORMS S OF 10N. PAPAGAYO 
GAP WINDS OF 20 KT AND SEAS OF 8 FT ARE FORECAST TO PERSIST FOR 
THE NEXT 48 HOURS. PANAMA GAP WINDS OF 20 KT AND SEAS LESS THAN 
8 FT ARE ALSO FORECAST FOR THE NEXT 30 HOURS. A TEHUANTEPEC GALE 
IS FORECAST IN 12 HOURS AS THE TAIL END OF A COLD FRONT PUSHES E 
OVER THE BAY OF CAMPECHE TO THE YUCATAN PENINSULA USHERING IN 
NORTHERLY WINDS. SOUTHWEST SWELL IS PUSHING N FROM SOUTH OF THE 
EQUATOR AND WILL COVER THE ENTIRE AREA WITHIN 48 HOURS. MERGING 
SEAS ARE FORECAST SOUTH OF TEHUANTEPEC WITHIN 24 HOURS. A 1002 
MB LOW IS W OF THE AREA NEAR 37N148W MOVING SLOWLY E. THE COLD 
FRONT WILL APPROACH 140W IN 48 HOURS WITH CONVECTION.     

IN THE UPPER LEVELS...AN UPPER LEVEL LOW IS CENTERED NEAR 
34N132W. THIS LOW IS THE EASTERN LOW IN AN OMEGA BLOCK. UPPER 
LEVEL PATTERNS N OF 20N ARE CHANGING VERY SLOWLY THUS THE 
SURFACE LOW AND FRONT W OF 140W IS APPROACHING THE AREA SLOWLY.  

$$
FORMOSA