000
AXPZ20 KNHC 231530
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC THU JUN 23 2011

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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...ITCZ/MONSOON TROUGH...
THE MONSOON TROUGH EXTENDS W FROM COSTA RICA NEAR 10N85W TO 
10N92W THEN TURNS NW PARALLEL TO CENTRAL AMERICA TO NEAR 
18N100W. THE MONSOON TROUGH RESUMES NEAR 18N110W AND EXTENDS SW 
THROUGH 10N119W TO 08N124W WHERE LOW LEVEL WINDS INDICATE THAT 
THE ITCZ BEGINS...AND EXTENDS W TO BEYOND 05N140W. SCATTERED 
MODERATE FROM 05N TO 13N BETWEEN 88W AND 100W. SCATTERED 
MODERATE ISOLATED STRONG WITHIN 90 NM S OF MONSOON TROUGH 
BETWEEN 110W AND 120W. THE MONSOON TROUGH IS EXPECTED TO 
REESTABLISH ITSELF ALONG THE COAST OF OLD MEXICO WITHIN 24 
HOURS...AND DRIFT FURTHER N OVER OLD MEXICO AND INTERIOR CENTRAL 
AMERICA BY LATE SAT. A TROPICAL WAVE OVER THE W CARIBBEAN IS 
EXPECTED TO MOVE NW OVER PORTIONS OF CENTRAL AMERICA THIS 
WEEKEND...BUT SHOULD LOSE IDENTITY IN THE STRONG SOUTHWESTERLY 
LOW LEVEL FLOW OVER THE PACIFIC WATER ALONG CENTRAL AMERICA.    

...DISCUSSION...
A LARGE ANTICYCLONE CENTERED NEAR 30N119W DOMINATES MOST OF THE 
DISCUSSION AREA WITH A VAST AREA OF MODERATE TO STRONG 
SUBSIDENCE OVER THE AREA N OF 12N W OF 110W. ASSOCIATED RIDGE 
AXIS EXTENDS SW TO 17N138W...AND NE ACROSS THE SW CONUS. 
AN UPPER LEVEL SHEAR AXIS IS APPROACHING THE NW PORTION OF THE 
AREA BUT IS EXPECTED TO MAKE LITTLE PROGRESS IN THE FACE OF THE 
STRONG UPPER LEVEL RIDGE. 

A NARROW UPPER LEVEL TROUGH EXTENDS FROM THE RIO GRANDE VALLEY 
OF TEXAS SW ACROSS NW MEXICO TO A SMALL CYCLONIC CIRCULATION 
OVER SRN BAJA CALIFORNIA NEAR 23N112W. THIS TROUGH SEPARATES THE 
ANTICYCLONIC FLOW OVER NW OLD MEXICO FROM UPPER LEVEL DIFFLUENT 
FLOW ASSOCIATED WITH A SECOND UPPER ANTICYCLONE CENTERED OVER 
MEXICO NEAR 21N99W. UPPER DIFFLUENT EASTERLY FLOW S OF THE 
ANTICYCLONE OVER MEXICO WAS ENHANCING CONVECTION OVER THE EAST 
PACIFIC FROM 05N TO THE COAST OF CENTRAL AMERICA. 

THE AREA OF UPPER LEVEL DIFFLUENT FLOW EXTENDS W ACROSS THE 
PACIFIC TO ALONG 120W AND WAS ENHANCING DEEP CONVECTION IN AN 
AREA OF LOW LEVEL CONVERGENCE TO THE S OF THE MONSOON TROUGH 
BETWEEN 110W AND 120W. 

FURTHER EAST AN UPPER TROUGH EXTENDS SW ACROSS THE NW CARIBBEAN 
TO A SHARP BASE OVER GUATEMALA. AN UPPER ANTICYCLONE IS OVER THE 
EXTREME SW CARIBBEAN WITH A RIDGE EXTENDING NW OVER HONDURAS. 
CONVECTION HAS FLARED UNDER THIS RIDGE AND ALONG THE MONSOON 
TROUGH THAT LIES PARALLEL TO CENTRAL AMERICA. THE DEBRIS 
MOISTURE SPREADS W OVER THE TROPICS TO THE N OF 05N MERGING WITH 
THE PREVIOUSLY DESCRIBED MOISTURE OVER THE EAST PACIFIC. 

AT THE SURFACE...A BROAD RIDGE COVERS THE AREA N OF 10N AND W OF 
120W. A SURGE OF NORTHERLY WINDS OF 20 KT HAS DIPPED INTO THE 
MARINE AREA NE OF THE RIDGE...GENERALLY TO THE N OF 27N BETWEEN 
127W AND 135W...AND IS ACCOMPANIED BY NORTHERLY SWELLS RESULTING 
IN COMBINED SEAS OF 9 FT ALONG 30N. THESE NE WINDS WILL SPREAD 
SW OVER THE NW PORTION OVER THE NEXT COUPLE OF DAYS.

LOW LEVEL SW WINDS CONTINUE AT 15 TO 20 KT OVER THE AREA S OF 
05N BETWEEN 85W AND 95W...WITH THE AFFECTED AREA SHIFTING NE 
OVER THE NEXT COUPLE OF DAYS. MIXED SOUTHERLY SWELLS ARE 
CONTRIBUTING TO 9 FT SEAS IN THE WATERS S OF 18N E OF 110W...AND 
OVER THE DEEP TROPICS TO THE S OF 05N BETWEEN 110W AND 130W. THE 
NORTHERN EXTENSION OF THESE 8 FT SEAS TO SHRINK TO THE WATERS S 
OF 12N BETWEEN 85W AND 125W BY SAT.

$$
COBB