Eastern Pacific Tropical Weather Discussion

000
AXPZ20 KNHC 050230
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
0405 UTC THU MAR 05 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0230 UTC. 

...SPECIAL FEATURES...

...GULF OF TEHUANTEPEC STORM WARNING...

STRONG HIGH PRESSURE BEHIND A COLD FRONT PUSHING SOUTHWARD INTO 
SOUTHERN MEXICO BY THU EVENING 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. WINDS ARE EXPECTED TO INCREASE TO 40 KT...GALE FORCE BY 
0600 UTC FRI MORNING WITH SEAS BUILDING TO 12 FT. WINDS ARE 
EXPECTED TO INCREASE FURTHER TO 50 KT...STORM FORCE BY FRI 
EVENING WITH SEAS BUILDING TO 18 TO 20 FT. GALE FORCE WINDS ARE 
FORECAST TO CONTINUE IN THE REGION THROUGH EARLY SUN...WITH SEAS 
TO 12 FT IN NE SWELL SPREADING SOUTHWARD ACROSS MOST OF THE EAST 
PACIFIC N OF 05N BETWEEN 95W AND 110W BY SUN. 

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

WIND CONVERGENCE IS VERY WEAK IN THE NORTHERN HEMISPHERE WITH 
THE AXIS OF THE ITCZ NOTED FROM 02N83W TO 05N96W TO 03N104W. THE 
PRIMARY CONVERGENCE ZONE IS BEGINNING TO SHIFTS SOUTH OF THE 
EQUATOR BETWEEN 105W AND1 40W. NO SIGNIFICANT CONVECTION WAS 
NOTED ALONG THE PORTION OF THE ITCZ N OF THE EQUATOR. 

LINGERING TROUGH EXTENDS FROM 07N115W TO 11N112W WITH SCATTERED 
MODERATE ISOLATED STRONG CONVECTION WELL REMOVED FROM THE TROUGH 
AND FOCUSED IN AN AREA FROM 08N TO 11N BETWEEN 108W AND 111W.

...DISCUSSION... 

A FAIRLY SHARP MID TO UPPER LEVEL TROUGH WITH SEVERAL EMBEDDED 
SHORTWAVES  EXTENDS FROM ARIZONA TO A BASE NEAR 17N125W. THE 
SURFACE TROUGH NOTED EARLIER FROM 22N106W TO 13N118W HAS 
DISSIPATED AS HIGH PRESSURE OVER THE EAST-CENTRAL PACIFIC BUILDS 
SE. 

A 1920 UTC HIGH RESOLUTION ASCAT PASS INDICATED AN AREA OF FRESH 
TRADES FROM 11N TO 14N W OF 125W. EXPECT THE TRADES TO WEAKEN 
SLIGHTLY THROUGH FRI AS HIGH PRES WELL N OF THE AREA SHIFTS 
EASTWARD AHEAD OF AN ADVANCING MID-LATITUDE COLD FRONT. 

PULSING GAP WIND FLOW DOMINATES THE REMAINDER OF THE FORECAST 
AREA E OF 95W...WITH MODERATE TO FRESH FLOW SPILLING ACROSS 
CENTRAL AMERICA INTO THE GULF OF PAPAGAYO. WINDS ARE EXPECTED TO 
REACH 25 KT DURING MAXIMUM DRAINAGE FLOW EARLY THU. STEADIER GAP 
WINDS ARE FORECAST BY EARLY FRI WITH SEAS BUILDING TO 9 FT.   

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 PEAK AT 
30 KT LOCALLY EARLY FRI WITH SEAS BUILDING TO 8 FT. 

$$ 
COBB