000
AXPZ20 KNHC 040305
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC FRI NOV 4 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0230 UTC.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH IS ALONG 13N88W TO 14N90W TO 07N103W. THE 
INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 07N103W TO 
10N125W TO 10N130W TO 08N140W. SCATTERED MODERATE CONVECTION IS 
WITHIN 120 NM EITHER SIDE OF THE ITCZ BETWEEN 123W AND 127W... 
AND ALSO WITHIN 120 NM S OF THE ITCZ BETWEEN 131W AND 137W.

...DISCUSSION...

GULF OF TEHUANTEPEC...A COLD FRONT CURRENTLY MOVING THROUGH THE 
W GULF OF MEXICO WILL PUSH SOUTHWARD THROUGH THE CHIVELA PASS 
BRINGING WINDS TO GALE FORCE OVER THE GULF OF TEHUANTEPEC LATER 
TONIGHT AND PERSISTING THROUGH FRI NIGHT. WINDS WILL DIMINISH TO 
20 KT BY SAT NIGHT WITH LINGERING 8 FT SWELL GENERATED BY THE 
EVENT PROPAGATING SOUTHWESTWARD AWAY FROM THE GULF OF 
TEHUANTEPEC.

GULF OF CALIFORNIA...SW WINDS WILL BECOME ESTABLISHED OVER THE 
NORTHERN GULF AS A COLD FRONT APPROACHES FROM THE NW. WINDS WILL 
REACH 20-25 KT FRI MORNING...INCREASING TO NEAR GALE FORCE FRI 
EVENING WITH LOCALLY HIGHER WINDS EXPECTED TO FUNNEL THROUGH W 
FACING PASSAGES. THE FRONT IS FORECAST TO WEAKEN AS IT PASSES 
THROUGH THE NORTHERN GULF SAT WITH WINDS DIMINISHING TO LESS 
THAN 20 KT SAT AFTERNOON.

ELSEWHERE E OF 110W...AN UPPER ANTICYCLONE IS CENTERED OVER EL 
SALVADOR NEAR 13N90W WITH AN UPPER TROUGH AXIS TO THE W 
EXTENDING FROM THE W COAST OF MEXICO NEAR 23N106W THROUGH 
10N105W TO THE EQUATOR NEAR 98W. CONFLUENCE ALOFT BETWEEN THE 
ANTICYCLONE AND TROUGH CONTINUES TO INHIBIT CONVECTION ALONG THE 
ITCZ AND MONSOON TROUGH...DESPITE PLENTY OF LOW LEVEL MOISTURE 
IN THE AREA.

W OF 110W...A COLD FRONT CURRENTLY LIES FROM THE U.S. CALIFORNIA 
COAST NEAR 35N121W EXTENDING INTO THE DISCUSSION AREA NEAR 
32N133W CONTINUING TO 30N140W. THIS FRONT WILL MOVE INTO THE N 
WATERS DURING THE NEXT SEVERAL HOURS...BRINGING FRESH NORTHERLY 
WINDS BEHIND IT. LARGE NW SWELL WILL BE THE MAIN HAZARD FROM 
THIS SYSTEM...WITH SIGNIFICANT WAVE HEIGHTS EXPECTED TO REACH 16 
FT OVER THE N CENTRAL WATERS BY FRI EVENING SUBSIDING TO 14 FT 
BY SAT EVENING. STRONG 1036 MB HIGH PRES CURRENTLY LIES BEHIND 
THIS COLD FRONT NEAR 40N150W. THE PRES GRADIENT BETWEEN THIS 
HIGH AND THE ITCZ TO THE S IS FORCING FRESH NE TRADE WINDS OVER 
THE W CENTRAL WATERS W OF 120W ACCORDING TO AN EARLIER ASCAT 
SCATTEROMETER PASS. THESE TRADES ARE FORECAST TO GRADUALLY SHIFT 
W BECOMING CONFINED W OF 130W BY SAT EVENING AS THE HIGH WEAKENS 
AND IS FORCED SW BY ANOTHER COLD FRONT.

$$
LEWITSKY