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Eastern Pacific Tropical Weather Discussion (Text)

000
AXPZ20 KNHC 192127
TWDEP 

TROPICAL WEATHER DISCUSSION                                      
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
2205 UTC WED JUN 19 2013

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 
2100 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...            
MONSOON TROUGH 10N86W TO 12N93W TO 09N101W TO 1008 MB LOW PRES 
NEAR 09N109W TO 11N126W. ITCZ 10N126W TO 12N130W TO 10N140W. 
SCATTERED MODERATE TO ISOLATED STRONG WITHIN 180 NM S OF THE 
MONSOON TROUGH E OF 105W. SCATTERED MODERATE WITHIN 90 NM NW 
QUADRANT OF LOW 1008 MB NEAR 09N109W. 

...DISCUSSION... 

AN UPPER TROUGH EXTENDS FROM NE MEXICO 16N102W 
TO AN UPPER CYCLONE CENTERED NEAR 16N1112W. THIS SUPPORTING A 
1008 MB SURFACE LOW PRES AREA NEAR 10N109W ALONG THE MONSOON 
TROUGH. E OF THE LOW...SCATTEROMETER DATA AND OBSERVATIONS FROM 
TOGA-TAO BUOY 43301 NEAR 08N95W INDICATE A SURGE OF MODERATE TO 
FRESH SW FLOW INTO THE MONSOON TROUGH. THIS IS SUPPORTING 
CLUSTERS OF MODERATE TO STRONG CONVECTION WITHIN 180 NM S OF THE 
MONSOON TROUGH E OF 105W. RECENT CRYOSAT DATA INDICATE SEAS TO 8 
FT IN THIS AREA.

FRESH N FLOW WAS NOTED IN THE GULF OF TEHUANTEPEC RELATED TO 
BROAD SCALE FLOW AHEAD OF THE DEVELOPING T.S. BARRY IN THE SW 
GULF OF MEXICO. BARRY HAS SINCE SHIFTED FARTHER W TOWARD 
VERACRUZ...LIKELY ALLOWING WINDS THROUGH THE TEHUANTEPEC AREA TO 
DIMINISH AND START TO SHIFT MORE SOUTHERLY. 

THROUGH THE NEXT 48 TO 72 HOURS...OPERATIONAL MODELS ARE IN 
REASONABLE AGREEMENT INDICATING THE LOW NEAR 10N109W WILL DRIFT 
SLOWLY W. MEANWHILE...A SECOND SURFACE LOW WILL FORM NEAR 
12N100W THROUGH SAT UNDER THE INFLUENCE OF THE QUASI-STATIONARY 
UPPER TROUGH. AN ASCAT PASS FROM 1545 UTC INDICATED SOME HINT OF 
THIS POSSIBLY ALREADY STARTING TO FORM ALONG THE MONSOON TROUGH. 

FARTHER WEST...BROAD TROUGH IS EVIDENT IN THE LOWER LEVELS OF 
THE ATMOSPHERE ALONG 130W AS NOTED IN GOES DERIVED WIND FIELDS. 
THE SURFACE WINDS INDICATE THAT THERE IS A KINK IN THE ITCZ IN 
THIS AREA. SCATTEROMETER AND ALTIMETER DATA FROM THE PAST 12 
HOURS ALSO INDICATES POCKETS OF 20 TO 25 KT WINDS IN THE 
GRADIENT BETWEEN THE INCIPIENT TROUGH AND HIGH PRES N OF THE 
AREA WITH SEAS TO 9 FT. GLOBAL MODELS INDICATE THE TROUGH WILL 
MIGRATE W OF 140W THROUGH LATE FRI.

A SURFACE RIDGE EXTENDS FROM 35N145W TO SOUTH OF THE BAJA 
PENINSULA. SHIP OBSERVATIONS AND ASCAT DATA INDICATE FRESH NW TO 
N WINDS BETWEEN THE HIGH PRES AND THE COAST OF BAJA...MAINLY N 
OF 23N E OF 125W. 

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CHRISTENSEN