000
AXPZ20 KNHC 222131
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SAT OCT 22 2011

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

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

...ITCZ/MONSOON TROUGH...
MONSOON TROUGH EXTENDS FROM 12N87W TO 12N93W TO 09N99W TO 
12N104W...THEN RESUMES FROM 1011 MB LOW PRES NEAR 18N113W TO 
SECOND LOW 1011 MB NEAR 11N117W TO 08N125W...THEN CONTINUES AS 
ITCZ TO 08N140W. SCATTERED MODERATE CONVECTION WITHIN 30 NM OF 
LINE FROM 23N107W TO 16N115W.

...DISCUSSION...
WESTERN PORTION OF MONSOON TROUGH HAS LIFTED NORTHWARD W OF 113W 
AND IS NO LONGER CONTINUOUS WITH EASTERN PORTION OF THE TROUGH E 
OF 104W. ANIMATED SAT IMAGERY SHOWS AN ELONGATED SW-NE ORIENTED 
TROUGH AXIS EXTENDING FROM THE SOUTHERN TIP OF BAJA CALIFORNIA 
THROUGH A LOW NEAR 18N113W TO ANOTHER LOW NEAR 11N117W...WITH 
MODERATELY ACTIVE CONVECTION ASSOCIATED WITH THE TROUGH DUE TO 
STRONG LOW LEVEL CONVERGENCE. A WEAK HIGH PRES RIDGE EXTENDS SE 
FROM 35N140W TO NEAR 23N113W.

SCATTEROMETER PASS AT 1622 UTC OVER THE GULF OF TEHUANTEPEC 
REVEALED NARROW BAND OF 25-30 KT WINDS EXTENDING FROM THE COAST 
OF MEXICO NEAR 16N95W TO 12N96W. THIS INDICATES PRES GRADIENT IN 
THE CHIVELAS PASS IS STILL SUPPORTING FRESH TO STRONG N-NE WINDS 
IN THE MORNING HOURS BUT WINDS SUBSIDE TO NEAR 20 KT BY EVENING.
GFS MODEL SHOWS WINDS INCREASING TO NEAR GALE FORCE BY LATE SUN 
OR EARLY MON IN RESPONSE TO THE SW CARIBBEAN LOW LIFTING N INTO 
THE NW CARIBBEAN AND BACKING FLOW ACROSS THE W GULF OF MEXICO. 
 
$$
MUNDELL