000
AXPZ20 KNHC 100255
TWDEP 

TROPICAL WEATHER DISCUSSION      
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC THU MAY 10 2012

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.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
MONSOON TROUGH ANALYZED FROM LOW PRES OVER COLOMBIA NEAR 06N75W 
1007 MB TO 06N90W TO 08N98W TO 08N106W TO 10N111W TO 05N130W. 
ITCZ AXIS FROM 03.5N137W TO BEYOND 04N140W. SCATTERED MODERATE 
ISOLATED STRONG CONVECTION NOTED WITHIN 90 NM N AND 240 NM S OF 
TROUGH BETWEEN 83W AND 94W. SCATTERED MODERATE TO STRONG 
CONVECTION NOTED WITHIN 150 NM EITHER SIDE OF TROUGH BETWEEN 
101W AND 115W. SCATTERED MODERATE ISOLATED STRONG CONVECTION 
NOTED WITHIN 120 NM N AND 60 NM S OF TROUGH BETWEEN 115W AND 
130W. SCATTERED MODERATE ISOLATED STRONG CONVECTION NOTED WITHIN 
60 NM N OF ITCZ W OF 137W. 

...DISCUSSION...
AT UPPER LEVELS...A FLATTENING TROUGH-RIDGE-TROUGH PATTERN 
CONTINUES ACROSS THE AREA EARLY TONIGHT...N OF 20N...AND 
CONTINUES TO SHIFT VERY SLOWLY EWD. THE MIDDLE/UPPER TROUGH W OF 
THE AREA YESTERDAY HAS WEAKENED AND SHIFTED NE TO ALONG 
139W/140W... WITH UPPER TROUGH EXTENDING SE TO NEAR 08N132W. A 
DEEP LAYERED TROUGH SWEEPING N OF THE HAWAIIAN ISLANDS IS ACTING 
TO FORCE THE AFOREMENTIONED TROUGH NE ACROSS THE BACKSIDE OF A 
SHORTWAVE RIDGE ALONG 125W. CUT OFF LOW ACROSS THE DESERT SW OF 
THE U.S. HAS MOVED SLOWLY SE PAST 24 HOURS AND IS NOW CENTERED 
OVER FAR NRN MEXICO NEAR 30N110W AND IS IGNITING WIDESPREAD 
CONVECTION WITHIN 240 NM OF CENTER ACROSS NRN SEMICIRCLE AND NE 
QUADRANT. S OF 20N E OF 124W...UPPER RIDGING PREVAILS TO 85W AS 
VERY ACTIVE CONVECTION NEAR THE MONSOON TROUGH AND ITCZ CONTINUE 
TO AID IN MAINTAINING DIVERGENT FLOW ALOFT. 

A 1036 MB HIGH HAS SHIFTED ENE IN THE PAST 24 HOURS...AND WAS 
LOCATED NNW OF THE AREA NEAR 41N141W...WITH RIDGE EXTENDING SE 
TO NEAR 14N104W. THE PRES GRADIENT BETWEEN THE RIDGE AND LOWER 
PRES ALONG CALIFORNIA AND THE NORTHERN BAJA CALIFORNIA PENINSULA 
IS RESULTING IN AN AREA OF 20 KT NLY WINDS NW OF LINE 30N128W TO 
23N140W. THIS LOW LEVEL PATTERN WILL PERSIST THROUGH THU 
AFTERNOON WITH INCREASING NLY SWELL. THE PRES GRADIENT ALONG THE 
SOUTHERN PERIPHERY OF THE RIDGE HAS DECREASED IN THE PAST FEW 
DAYS AND THE NE TRADES ARE LESS THAN 20 KT N OF THE ITCZ. LATE 
MORNING AND EARLY AFTERNOON SCATTEROMETER DERIVED WINDS INDICATE 
THAT MONSOON FLOW S OF THE TROUGH HAS BEGUN TO INCREASE...AND 
WAS 15-20 KT BETWEEN 97W AND 114W...RESULTING IN SOME OF THE 
STRONGER CONVECTION DESCRIBED ABOVE. NO SIGNIFICANT CHANGES ARE 
EXPECTED IN THIS OVERALL WEATHER SCENARIO INTO THE WEEKEND AS 
HIGH PRES WILL REMAIN WELL N AND NW OF THE AREA...AND MONSOONAL 
FLOW WILL REMAIN WELL ESTABLISHED E OF 120W.  

$$
STRIPLING