000
AXPZ20 KNHC 261521
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC MON MAR 26 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1230 UTC.

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

THE ITCZ AXIS EXTENDS FROM 10N102W TO 07N116W TO 06N140W. 
SCATTERED MODERATE CONVECTION LIES WITHIN 90 NM N OF AXIS 
BETWEEN 105W AND 122W AND ELSEWHERE FROM 08N TO 11N BETWEEN 120W 
AND 127W.

...DISCUSSION...

THE PROGRESSIVE NORTHERN STREAM PATTERN WILL SEND A NEW COLD 
FRONT INTO NW WATERS OVERNIGHT TONIGHT. THIS FRONT WILL NOT BE 
AS STRONG AS THE PREVIOUS FRONT THAT IS CURRENTLY DISSIPATING 
OVER BAJA CALIFORNIA. DEEP LAYER RIDGING IS QUICKLY BUILDING IN 
BEHIND THAT FRONT AFTER ITS SUPPORTING UPPER TROUGH TURNED 
NEGATIVE TILT. SUBSIDING SWELL FROM THAT DISSIPATING FRONT 
CONTINUES TO TRAVEL SOUTHWARD THROUGH THE FORECAST AREA...WITH 
THE 0510 UTC JASON2 PASS SHOWING SEAS TO 15 FT. FRESH TRADE 
WINDS HAVE RETURNED TO THE AREA FROM 09N TO 15N W OF 122W AS 
HIGH PRES HAS BUILT E BEHIND THIS FRONT. THE WEAK HIGH WILL MOVE 
TO NE FORECAST WATERS OVERNIGHT TONIGHT...FORCED EASTWARD BY THE 
NEW COLD FRONT MOVING INTO NW WATERS AROUND THAT TIME. THE PRES 
GRADIENT BETWEEN THE HIGH AND WEAK TROUGHING OVER CENTRAL MEXICO 
WILL ALLOW FRESH NW TO N WINDS TO PERSIST ALONG THE W COAST OF 
BAJA CALIFORNIA INTO WED MORNING. FRESH WESTERLY WINDS 
ASSOCIATED WITH THE NEW COLD FRONT MOVING INTO NW WATERS TONIGHT 
WILL DISSIPATE BY WED...BUT NW SWELL WILL CONTINUE TO PROPAGATE 
INTO THE FORECAST AREA WITH SEAS EXPECTED TO REACH 12 FT BEHIND 
THE NEW COLD FRONT. THIS NEW FRONT WILL DISSIPATE WED. 

FARTHER S...THE SOUTHERN STREAM UPPER JET GENERALLY LIES BETWEEN 
10N AND 20N W OF 130W AND THEN SPLITS WITH A BRANCH CONTINUING 
ALONG 15N TO 120W AND A SECOND BRANCH MOVING S OF THE EQUATOR. 
THE DIFFLUENT LEFT FRONT QUADRANT OF THE NORTHERN BRANCH IS 
LIFTING LOW LEVEL MOISTURE POOLED ALONG THE ITCZ. THE RESULTING 
CONVECTION ALONG THE ITCZ IS DESCRIBED IN THE SECTION ABOVE. 

A PERSISTENT SURFACE TROUGH LIES FROM 08N81W TO 04N87W TO 
02N95W. THE CONVECTION THAT WAS PREVIOUSLY NOTED NEAR THIS 
TROUGH HAS DISSIPATED OVER THE LAST SEVERAL HOURS AS 45-55 KT SW 
WINDS ASSOCIATED WITH THE UPPER JET OVER THE CARIBBEAN MOVED 
OVER THE SURFACE TROUGH.

$$
SCHAUER