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Eastern Pacific Tropical Weather Discussion (Text)

000
AXPZ20 KNHC 042202
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
2205 UTC WED MAR 04 2015

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 
2130 UTC. 

...SPECIAL FEATURES...

...GULF OF TEHUANTEPEC GALE WARNING...

STRONG HIGH PRESSURE BEHIND A COLD FRONT PUSHING SOUTHWARD INTO 
SOUTHERN MEXICO WILL INDUCE A TIGHT PRESSURE GRADIENT ACROSS THE 
ISTHMUS OF TEHUANTEPEC AND FUNNEL COLD AIR THROUGH THE CHIVELA 
PASS INTO THE GULF OF TEHUANTEPEC OVERNIGHT THU. EXPECT SUDDEN 
INCREASE IN WINDS TO GALE FORCE BY 0600 UTC EARLY FRI MORNING... 
FOLLOWED BY AN EXTENDED PERIOD OF STRONG GALE FORCE....POSSIBLY 
STORM FORCE WINDS IN THE REGION THROUGH SUN MORNING. MAX SEAS 
WILL RAPIDLY BUILD TO 15-16 FT FRI MORNING ...AND REACH A PEAK 
AROUND 18-20 FT FRI NIGHT INTO SAT.

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

WIND CONVERGENCE NEGLIGIBLE IN THE NORTHERN HEMISPHERE TODAY AS 
PRIMARY CONVERGENCE ZONE SHIFTS SOUTH OF THE EQUATOR. WEAK ITCZ 
IS ANALYZED FROM 06N132W TO 06N140W. NO SIGNIFICANT CONVECTION.

LINGERING TROUGH EXTENDS FROM 07N115W TO 11N112W WITH SCATTERED 
MODERATE ISOLATED STRONG CONVECTION FROM 08N TO 10N BETWEEN 111W 
AND 113W.

...DISCUSSION... 

A FAIRLY SHARP MID TO UPPER LEVEL TROUGH EXTENDS FROM SOUTHERN 
CALIFORNIA/ARIZONA TO A BASE NEAR 17N125W. THIS TROUGH IS 
PROVIDING LIMITED SUPPORT FOR A SURFACE TROUGH FROM 22N106W TO 
13N118W.  

SCATTEROMETER DATA SHOWS A SMALL AREA OF FRESH TRADES CENTERED 
NEAR 14N133W. EXPECT TRADES TO WEAKEN SLIGHTLY THROUGH FRI AS 
HIGH PRES WELL N OF THE AREA MOVES AWAY AHEAD OF A MID-LATITUDE 
COLD FRONT. 

GAP WIND FLOW DOMINATES THE FORECAST AREA E OF 110W...WITH THE 
TYPICAL GAP AREAS SEEING MODERATE TO FRESH FLOW SPILLING ACROSS 
CENTRAL AMERICA INTO THE EAST PACIFIC FROM THE CARIBBEAN. MOST 
OF THESE LOCATIONS WILL SEE WINDS REACHING 25 KT DURING MAXIMUM 
DRAINAGE FLOW AGAIN TONIGHT...THEN WEAKEN THU.

NW WINDS ARE EXPECTED TO INCREASE TO 20 TO 25 KT THU NIGHT IN 
NORTHERN GULF OF CALIFORNIA AS TROUGHING DEVELOPS ACROSS NW 
MEXICO AND HIGH PRES BUILDS W OF CALIFORNIA. WINDS WILL CONTINUE 
THROUGH FRI NIGHT WITH SEAS BUILDING LOCALLY TO 8 FT. 

$$ 
COBB