000
AXPZ20 KNHC 220937
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC WED FEB 22 2012

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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

MONSOON TROUGH NOT ANALYZED. ITCZ AXIS 03N110W TO 05N123W TO 
04N135W TO BEYOND 02N140W. SCATTERED MODERATE CONVECTION FROM 
04N TO 06N BETWEEN 122W AND 134W. ISOLATED MODERATE CONVECTION 
FROM 02N TO 04N BETWEEN 125W AND 130W. A DIFFLUENT PATTERN ALOFT 
IS HELPING TO INDUCE THIS CONVECTIVE ACTIVITY.

...DISCUSSION...

BROAD UPPER TROUGHING PREVAILS ACROSS N PORTIONS OF THE FORECAST 
AREA EXTENDING FROM NORTHERN BAJA CALIFORNIA TO 24N130W TO 
BEYOND 25N140W. A CUT-OFF LOW HAS DEVELOPED ALONG THE TROUGH 
AXIS NEAR 28N115W. A 70-90 KT UPPER JET CURRENTLY LIES SE OF THE 
TROUGH. THIS JET IS TRANSPORTING ABUNDANT MID AND HIGH LEVEL 
MOISTURE NORTHEASTWARD ACROSS N-CENTRAL MEXICO.

A PERSISTENT NEGATIVE TILT UPPER TROUGH EXTENDS FROM NEAR 
14N120W TO 06N115W. THIS TROUGH REMAINS LOCATED TO THE W OF A 
STRONG UPPER RIDGE THAT DOMINATES THE CARIBBEAN SEA...CENTRAL 
AMERICA...SE MEXICO AND THE E PACIFIC WATERS N OF 06N E OF 100W. 
STRONG SUBSIDENCE COVERS THIS ENTIRE AREA SUPPRESSING CONVECTION.

AT THE SURFACE...STRONG HIGH PRES CENTERED NEAR 37N137W EXTENDS 
A RIDGE SE ACROSS THE FORECAST WATERS TO NEAR 20N118W. PRES 
GRADIENT S OF THIS 1037 MB HIGH IS MAINTAINING FRESH TO STRONG 
NE TRADES W OF 125W. SCATTEROMETER DATA PROVIDED OBSERVATIONS OF 
THESE WINDS. THE HIGH WILL SHIFT NE AND WEAKEN THU AS A COLD 
FRONT MOVES TOWARD THE PAC NW COAST. NE TRADE WINDS WILL THEN 
DIMINISH TO AROUND 15-20 KT W OF 120W AND AREA OF FRESH NE WINDS 
WILL SHRINK SOUTHWARD. GALE FORCE WINDS ARE EXPECTED TO DEVELOP 
ALONG THE COAST OF CALIFORNIA THU...WHICH WILL BRING ANOTHER 
SURGE OF NLY SWELL INTO NORTHERN PORTION BETWEEN 120W AND 130W. 
LIGHT TO MODERATE NE-E TRADE WINDS PREVAIL ELSEWHERE ACROSS MOST 
OF THE REGION. 

LONG PERIOD NW SWELL GENERATED FAR N-NW OF THE AREA CONTINUES TO 
SWEEP INTO THE TROPICAL EAST PACIFIC WITH WAVE HEIGHTS SUBSIDING 
AS THE SWELL MOVES SE FROM ITS SOURCE REGION. NW WAVES ARE MIXING
WITH NE WIND WAVES BEING GENERATED LOCALLY BY ENHANCED NE TRADE 
WINDS BETWEEN 06N AND 24N W OF 125W. 

...GAP WINDS...

GULF OF PAPAGAYO...FRESH TO STRONG EASTERLY TRADE WINDS IN THE 
SW CARIBBEAN WILL PUSH THROUGH GAPS IN TERRAIN OVER NICARAGUA 
INTO THE GULF OF PAPAGAYO WHERE FRESH TO STRONG NE-E WINDS ARE 
EXPECTED EARLY THIS MORNING DUE TO LOCAL DRAINAGE FLOW. THIS 
WEATHER PATTERN WILL PERSIST THROUGH THU THEN DIMINISH BELOW 20 
KT THU NIGHT. 

GULF OF PANAMA...STRONG NE FLOW FROM THE SW CARIBBEAN WILL PUSH 
ACROSS THE ISTHMUS OF PANAMA INTO THE GULF OF PANAMA THROUGH THU 
MORNING. SHIP CALL SIGN ZCDF4 SAILING ACROSS THE AREA WAS 
REPORTING NLY WINDS OF 30 KT...AROUND 4-5 KT HIGHER THAN MODEL. 
THE O304 UTC ASCAT PASS INDICATED NLY WINDS OF 20 KT. EXPECT 
WINDS OF 20 TO 25 KT ACROSS THE GULF OF PANAMA THIS MORNING THEN 
WINDS WILL DIMINISH TO 20 KT THROUGH THU MORNING. SEAS WILL BE 
LESS THAN 8 FT.

LOOKING AHEAD...THE NEXT GULF OF TEHUANTEPEC GAP WIND EVENT IS 
FORECAST TO OCCUR DURING THE UPCOMING WEEKEND AS THE NEXT COLD 
FRONT MOVES ACROSS THE WESTERN GULF OF MEXICO. 

$$
GR