000
AXPZ20 KNHC 230237
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0215 UTC.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS FROM NORTHERN COSTA RICA TO 9N90W AND 
NW TO 16N99W...THEN RESUMES AT 15N111W TO 7N125W WHERE IT 
TRANSFORMS INTO THE ITCZ TO 5N131W AND TO BEYOND 5N140W. 
SCATTERED MODERATE CONVECTION IS WITHIN 120 NM S OF THE TROUGH 
BETWEEN 81W-84W...AND ALSO BETWEEN 110W-114W.

...DISCUSSION...

AN UPPER TROUGH IS APPROACHING THE FAR NW PORTION PRECEDED BY
SOUTHERLY UPPER FLOW OBSERVED TO THE N OF 20N W OF 130W. TO ITS
E...AN UPPER LEVEL ANTICYCLONE IS LOCATED NEAR 25N125W...WITH A 
RIDGE EXTENDING NE TO SOUTHERN CALIFORNIA AND THE SW U.S. ANOTHER
RIDGE EXTENDS FROM THE ANTICYCLONE SW TO NEAR 18N140W. OVER THE
FAR EASTERN PORTION OF THE AREA...E OF THE ANTICYCLONE...THE TAIL
END OF AN UPPER TROUGH EXTENDS SW INTO THE AREA FROM WESTERN 
TEXAS SW TO OVER SOUTHERN BAJA CALIFORNIA AND TO NEAR 20N115W. 
SATELLITE WATER VAPOR IMAGERY SHOWS AMPLE MODERATE SUBSIDENCE 
AND RESULTANT DRY AIR COVERING THE ENTIRE AREA W OF A LINE FROM 
24N106W TO 14N125W AND TO THE EQUATOR AT 135W. THE ANTICYCLONE IS
FORECAST TO MOVE NE AND WEAKEN AS IT BECOMES SITUATED OVER NW 
MEXICO LEAVING THE AREA UNDER A WEAK PRES PATTERN.

A SMALL UPPER ANTICYCLONE IS IDENTIFIED OVER WESTERN MEXICO NEAR
18N101W. A ZONE OF UPPER DIFFLUENCE BETWEEN THIS ANTICYCLONE AND
THE ONE NEAR 25N125W IS CREATING A VENTILATION AREA FOR 
CONVECTION ASSOCIATED WITH THE MONSOON TROUGH TO REMAIN RATHER 
ACTIVE BETWEEN 110W-114W...ALTHOUGH IT HAS WEAKENED OVER THE 
PAST FEW HOURS. THE UPPER LEVEL MOISTURE DUE TO THIS CONVECTION 
IS SPREADING SOUTHWESTWARD WITH THE AID OF MODERATE TO STRONG NE 
WINDS AROUND THE SOUTHERN PERIPHERY OF THE ANTICYCLONE NEAR 
25N124W...AND REACHES TO NEAR 128W BEFORE IT EVAPORATES IN THE 
SUBSIDENCE UPPER ENVIRONMENT.

STRONG UPPER LEVEL ELY WINDS FOUND OVER THE FAR EASTERN SECTION 
OF THE AREA TO THE S OF MID/UPPER RIDGING THAT COVERS MUCH OF 
CENTRAL AMERICA ARE TRANSPORTING UPPER LEVEL MOSITURE IN THE 
FORM OF SCATTERED TO BROKEN HIGH CLOUDS WESTWARD TO JOIN UP WITH
THAT SOME OF THE MOISTURE GENERATED BY THE MONSOON TROUGH 
CONVECTION.

AT THE SURFACE...A BROAD AND RATHER WEAK RIDGE COVERS THE AREA
N OF 13N AND W OF 122W. A PARTIAL ASCAT PASS FROM YESTERDAY
AFTERNOON SHOWED A NLY SURGE OF WINDS TO 20 KT BEGINNING TO MOVE 
INTO THE FAR NORTHERN WATERS N OF 28N AND BETWEEN 127W-135W WITH 
SEAS TO 8 FT. OVER THE NEXT 36-48 HRS THE BOUNDARY OF THIS AREA
OF 20 KT N WINDS WILL BECOME ESTABLISHED TO THE N OF 28N BETWEEN 
121W-134W...WITH WAVEWATCH GUIDANCE FORECASTING SEAS TO INCREASE
TO THE RANGE OF 8-10 FT IN A N SWELL.

THE GFS MODEL IS SUGGESTING THAT A LOW FORMS OVER THE FAR EASTERN
PART OF THE AREA IN ABOUT 36 HOURS NEAR 10N86W. THE GFS IS RATHER
MORE AGGRESSIVE THAN THE OTHER GLOBAL MODELS WITH THIS POSSIBLE
FEATURE...SO WILL GO ON THE WEAKER SIDE FOR NOW FOR THE NEXT
ISSUED HIGH SEAS FORECAST.

OTHERWISE...THE REMAINDER OF THE AREA REMAINS RATHER TRANQUIL 
WITH JUST A SMALL AREA OF SLY WINDS IN THE RANGE OF 15-20 KT S 
OF 4N E OF 95W. BY 24 HRS THE WINDS WILL BE MAINLY S-SW 15-20 KT 
S OF 4N BETWEEN 84W-96W WITH A S SWELL BUILDING SEAS TO 9 
FT...AND BY 48 HRS IT SHOULD BE CONFINED FROM 3N-6N BETWEEN 
87W-98W. THE REMAINDER OF THE AREA E OF A LINE FROM 19N104W TO 
THE EQUATOR AT 135W SHOULD SEE RATHER LIGHT WINDS WITH SEAS 8-10 
FT PRIMARILY IN A S SWELL...HIGHEST OF THE SEAS SHOULD BE S OF 
ABOUT 5N.

$$
AGUIRRE