000
AXPZ20 KNHC 251510
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SUN MAR 25 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 
1300 UTC.

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

THE ITCZ AXIS EXTENDS FROM 01N105W TO 06N123W TO 05N135W. NO 
SIGNIFICANT CONVECTION LIES NEAR THE AXIS.

...DISCUSSION...

AN AMPLIFIED UPPER LEVEL TROUGH ALONG 125W N OF 20N WILL TURN 
NEGATIVE TILT AND MOVE INTO THE WESTERN U.S. AND NW MEXICO 
THROUGH MON. A 70-90 KT NORTHERN STREAM UPPER JET ROUNDS THE 
TROUGH NEAR 30N WHILE THE SOUTHERN STREAM JET EXTENDS ZONALLY 
BETWEEN 05N AND 20N TO THE BASE OF THE TROUGH NEAR 125W. A BAND 
OF HIGH LEVEL MOISTURE IS BEING ADVECTED NE AHEAD OF THE TROUGH 
FROM 20N120W TO THE NORTHERN GULF OF CALIFORNIA AND A SECOND 
BAND LIES BETWEEN 10-20N W OF 125W ASSOCIATED WITH THE SOUTHERN 
STREAM JET. MODERATE TO STRONG SUBSIDENCE WITH DRY AIR THE 
MIDDLE AND UPPER LEVELS IS N OF 20N W OF 125W. ELSEWHERE... A 
BROAD UPPER LEVEL RIDGE IS CENTERED FROM CENTRAL TEXAS THROUGH 
MEXICO TO 10N105W. THIS RIDGE WILL SHIFT E AHEAD OF THE 
NEGATIVELY TILTED TROUGH MON INTO TUE. 

THE AFOREMENTIONED UPPER LEVEL TROUGH IS ASSOCIATED WITH A 
SURFACE COLD FRONT OVER N WATERS FROM 30N120W TO 25N124W TO 
22N132W. W TO NW WINDS HAVE INCREASED GALE FORCE BEHIND THE 
FRONT NEAR 32N132W ACCORDING TO THE 0532 UTC ASCAT PASS AS THE 
SURFACE LOW MAKES ITS CLOSEST APPROACH TO THE FORECAST AREA. THE 
1004 MB LOW CURRENTLY LIES NEAR 34N126W. GALE FORCE WINDS WITH 
THIS LOW ARE EXPECTED TO REMAIN N OF 30N. STRONG WINDS S OF 30N 
WILL QUICKLY DIMINISH MON AS THE SUPPORTING TROUGHING ALOFT 
TURNS NEGATIVE TILT ALLOWING RIDGING TO BUILD TO ITS 
SOUTH...BREAKING UP THE DEEP LAYER TROUGHING. THE FRONT WILL 
WEAKEN SHARPLY BEFORE DISSIPATING OVER THE FORECAST AREA TUE. 
LARGE NW SWELL TO 21 FT CURRENTLY LIES W OF THE FRONT. THE FRONT 
WILL DISSIPATE BY 48 HOURS WITH THE LARGE NW SWELL GRADUALLY 
SUBSIDING TO 8-10 FT BY TUE MORNING.

FRESH TRADE WINDS...WHICH HAVE TAKEN A HIATUS DUE TO THE FRONT 
BREAKING UP THE SUBTROPICAL RIDGE TO THE N...WILL RETURN BY MON 
NIGHT AS HIGH PRES BUILDS E BEHIND THE FRONT. THE WEAK HIGH WILL 
LIE OVER NE WATERS BY TUE MORNING...FORCED EASTWARD BY ANOTHER 
COLD FRONT MOVING INTO NW WATERS. 

FARTHER S...A PERSISTENT SURFACE TROUGH LIES FROM 10N86W TO 
05N90W TO 02N99W. SCATTERED MODERATE CONVECTION CAN BE FOUND 
WITHIN 210 NM SE OF TROUGH BETWEEN 88W AND 98W AND WELL AS 
WITHIN 75 NM OF THE COAST OF PANAMA BETWEEN 81W AND 84W. 
MOSITURE POOLED SOUTH OF THE SURFACE TROUGH IS BEING LIFTED BY 
UPPER LEVEL DIFFLUENCE ASSOCIATED WITH THE REAR RIGHT QUADRANT 
OF THE UPPER JET OVER THE CARIBBEAN. 

GAP WINDS...
GULF OF CALIFORNIA...STRONG S-SW WINDS LIE IN THE FAR NORTHERN 
GULF OF CALIFORNIA N OF 30N. THESE WINDS ARE FORECAST TO 
CONTINUE THROUGH MON MORNING AHEAD OF THE WEAKENING COLD FRONT 
CURRENTLY APPROACHING BAJA CALIFORNIA.

$$
SCHAUER