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Eastern Pacific Tropical Weather Discussion (Text)

000
AXPZ20 KNHC 300957
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
1005 UTC FRI JAN 30 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC. 

...SPECIAL FEATURES...                                           
GULF OF TEHUANTEPEC GALE WARNING...A TIGHT PRESSURE GRADIENT 
ACROSS SOUTHERN MEXICO CONTINUES TO SUPPORT A LONG DURATION 
MINIMAL GALE EVENT IN THE GULF OF TEHUANTEPEC. A SCATTEROMETER 
PASS AT 0400 UTC SHOWED MAX WINDS AROUND 32 KT...AN INDICATION 
THE INTENSITY MAY BE WANING OUTSIDE THE PEAK DIURNAL DRAINAGE 
FLOW PERIOD IN THE EARLY MORNING. A LARGE AREA OF 8-10 FT SEAS 
EXISTS FROM 03N TO 14N BETWEEN 93W AND 108W. THE GRADIENT WILL 
SLOWLY WEAKEN THROUGH SAT...WITH GALE FORCE WINDS ENDING BY SAT 
MORNING AS WINDS IN SW GULF OF MEXICO VEERS TO SE RETURN FLOW. 

GULF OF PAPAGAYO GALE WARNING...A TIGHT PRES GRADIENT IN THE FAR 
WESTERN CARIBBEAN SEA INTO CENTRAL AMERICA WILL REMAIN STRONG 
THIS MORNING. AFTERWARD...WINDS WILL DIMINISH TO FRESH TO STRONG 
AND DECREASE CONSIDERABLY IN AREAL COVERAGE. SWELL FROM PAPAGAYO 
IS COMBINING WITH SEAS GENERATED IN TEHUANTEPEC BUT WILL SUBSIDE 
AND SHRINK EASTWARD AS WINDS DIMINISH THIS WEEKEND.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...           
ITCZ AXIS EXTENDS FROM 04N91W TO 05N127W TO 07N140W. SCATTERED 
MODERATE CONVECTION WITHIN 75 NM OF AXIS BETWEEN 115W AND 120W.  

...DISCUSSION...                                                
UPPER LEVEL DIVERGENCE ASSOCIATED WITH A TROUGH ALONG 117W N OF 
10N IS TRIGGERING A LARGE AREA OF SHOWERS ACROSS NW MEXICO AND 
THE BAJA PENINSULA. THE TROUGH WILL SHIFT EASTWARD TODAY THEN 
FORM A CUT-OFF A LOW OVER NORTHERN ARIZONA SAT. 

1026 MB SUBTROPICAL HIGH NEAR 35N132W EXTENDS A RIDGE SOUTHWARD 
TO 18N139W. ASCAT SCATTEROMETER PASSES SHOW FRESH TO STRONG NE 
TRADES W OF 135W N OF THE ITCZ. FRESH TRADE WINDS ARE EXPECTED 
TO CONTINUE W OF 125W THROUGH EARLY SUN.

THE PRESSURE GRADIENT BETWEEN A HIGH IN THE GREAT BASIN AND 
TROUGHING W OF SIERRA MADRE OCCIDENTAL IS INDUCING FRESH TO 
STRONG NW WINDS IN THE SOUTH-CENTRAL GULF OF CALIFORNIA...WITH 
HIGHEST WINDS OVER 25 KT NEAR 27N BASED ON 0400 UTC ASCAT PASS. 
WINDS ARE EXPECTED TO DIMINISH BELOW 20 KT BY THIS AFTERNOON. 

FRESH TO STRONG WINDS WILL CONTINUE TO PULSE IN THE GULF OF 
PANAMA THIS MORNING. THE PRESSURE GRADIENT OVER SOUTHERN CENTRAL 
AMERICA WILL WEAKEN TODAY AND DECREASE TO 20 KT OR LESS BY THIS 
AFTERNOON WITH SEAS LESS THAN 8 FT. 

$$ 
MUNDELL