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Eastern Pacific Tropical Weather Discussion (Text)

000
AXPZ20 KNHC 012146
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
2205 UTC SUN FEB 01 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 
2030 UTC. 

...SPECIAL FEATURES...

GULF OF TEHUANTEPEC GALE WARNING...SPLIT FLOW OVER NORTH AMERICA 
WILL SEND A NORTHERN STREAM TROUGH THROUGH THE MISSISSIPPI 
VALLEY OVERNIGHT AND THROUGH THE EASTERN SEABOARD OF THE UNITED 
STATES MON NIGHT. THE ASSOCIATED COLD FRONT WILL PASS S THROUGH 
THE GULF OF MEXICO...MOVING THROUGH CHIVELA PASS BEFORE SUNSET 
ON MON. A QUICK BURST OF 30-35 KT WINDS WILL OCCUR IN THE GULF 
OF TEHUANTEPEC AFTER THE FRONTAL PASSAGE THROUGH SUNRISE TUE. 
MEANWHILE...A CUT OFF LOW WITHIN THE SOUTHERN STREAM CURRENTLY 
OVER THE BAJA CALIFORNIA PENINSULA WILL MOVE EASTWARD INTO NW 
MEXICO...ALLOWING THE MID TO LOW LEVEL FLOW OVER THE GULF OF 
MEXICO TO SHIFT MORE SOUTHEASTERLY AHEAD OF THE SYSTEM BY TUE. 
THE GALE WARNING IS FORECAST EXPIRE AFTER SUNRISE TUE AS A 
RESULT. SEAS WILL RAPIDLY BUILD TO 10-12 FT TUE MORNING. 

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

THE MONSOON TROUGH AXIS WAS ANALYZED FROM 09N84W TO 06N92W. THE 
ITCZ AXIS WAS ANALYZED FROM 06N92W TO 06N100W TO 04N100W TO 
08N120W TO 06N140W. SCATTERED MODERATE CONVECTION WAS WITHIN 150 
NM EITHER SIDE OF THE AXIS BETWEEN 113W AND 123W AS WELL AS 
WITHIN 210 NM S OF THE AXIS W OF 136W.

...DISCUSSION...

A 1026 MB SUBTROPICAL HIGH PRESSURE CENTER NEAR 32N132W SENDS A 
RIDGE AXIS SE TO SOCORRO ISLAND AND ANOTHER SW THROUGH 25N140W. 
SCATTEROMETER PASSES PRIOR TO 1900 UTC SHOW FRESH TO STRONG NE 
TRADES S OF THESE RIDGE AXES OVER WATERS JUST N OF THE ITCZ AND 
W OF 130W. THIS AREA OF FRESH TO STRONG TRADE WINDS HAS SHRUNK 
WESTWARD AND SHOULD GRADUALLY WANE OVER W WATERS TONIGHT AS THE 
DRIVING HIGH PRESSURE CENTER WEAKENS AND SHIFTS NORTHEASTWARD. 
SEAS OVER 8 FT WITHIN THE TRADE WIND BELT ARE EXPECTED TO SHRINK 
WESTWARD OVER THE NEXT TWO DAYS AS THE WINDS COME DOWN A NOTCH.

AS MENTIONED IN THE SPECIAL FEATURES SECTION ABOVE...A MID TO 
UPPER LEVEL LOW HAS CUT OFF FROM THE NORTHERN STREAM AND LIES 
OVER THE BAJA CALIFORNIA PENINSULA. SOUTHWEST FLOW ON THE SE 
SIDE OF THIS CUT OFF LOW IS PUMPING MOISTURE INTO THE CENTRAL 
MEXICAN COAST. CURRENTLY...CONVECTION IS PRIMARILY FOCUSED ON A 
SURFACE TROUGH FROM 22N105W TO 17N108W TO 12N114W ACCORDING TO 
LIGHTNING DATA...BUT WIDESPREAD SHOWERS CAN BE FOUND OVER MUCH 
OF MAINLAND MEXICO BETWEEN 19N AND 26N. THE CUT OFF LOW IS 
FORECAST TO SLOWLY MOVE EASTWARD INTO NW MEXICO....BUT THE 
LOCATION OF THE SW JET PROPELLING MOISTURE INTO MEXICO SHOULD 
CHANGE LITTLE. THIS WILL KEEP THE PRECIPITATION ASSOCIATED WITH 
THE SYSTEM FOCUSED ALONG THE COAST BETWEEN MANZANILLO AND 
MAZATLAN INLAND TO N CENTRAL AND NORTHEASTERN MEXICO THROUGH THE 
END OF THE FORECAST PERIOD ON TUE.

GAP WINDS...                                                    

GULF OF PAPAGAYO...THE 1552 UTC ASCAT-B PASS OBSERVED 20-25 KT 
NE WINDS ACROSS THE GULF OF PAPAGAYO AND DOWNWIND TO NEAR 87W. 
WHILE THE PRESSURE GRADIENT CONTINUES TO WEAKEN OVER THE SW 
CARIBBEAN...WINDS ARE EXPECTED TO CONTINUE AT A FRESH TO STRONG 
BREEZE WITH SEAS TO 8 FT IN THE GULF OF PAPAGAYO OVERNIGHT 
TONIGHT. THE STRONG BREEZE SHOULD TAKE A BRIEF REPRIEVE DURING 
THE DAY MON BEFORE BECOMING REINVIORATED BY BUILDING HIGH 
PRESSURE OVER CENTRAL AMERICA BEHIND THE AFOREMENTIONED COLD 
FRONT MOVING THROUGH CHIVELA PASS AND THE ASSISTANCE OF DRAINAGE 
FLOW OFF THE LAND LATE MON NIGHT AND EARLY TUE MORNING. THE 
BUILDING PRESSURE GRADIENT WILL ALLOW A FRESH BREEZE TO PERSIST 
INTO TUE AFTERNOON...WITH SEAS BUILDING TO AROUND 9 FT.

$$ 
SCHAUER