000
AXPZ20 KNHC 091533
TWDEP 

TROPICAL WEATHER DISCUSSION      
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED MAY 09 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
MONSOON TROUGH IS FROM 05N77W TO 06N90W TO 09N97W TO 07N105W TO 
09N122W. ITCZ IS FROM 09N122W TO 04N140W. SCATTERED MODERATE 
CONVECTION IS FROM 01N TO 05N BETWEEN 77W AND 84W...AND FROM 05N 
TO 12N BETWEEN 102W AND 120W. SCATTERED MODERATE TO ISOLATED 
STRONG CONVECTION IS FROM 03N TO 07N W OF 125W.

...DISCUSSION...
AN UPPER LEVEL RIDGE IS ACROSS THE NW PORTION OF THE DISCUSSION 
AREA N OF 15N W OF 120W. DOWNSTREAM UPPER LEVEL TROUGH EXTENDS 
FROM A CYCLONIC CIRCULATION OVER NW MEXICO NEAR 30N112W S 
ACROSS THE CENTRAL BAJA CALIFORNIA PENINSULA TO 20N112W. A 70-90 
KT JETSTREAM IS OVER THE SOUTHERN PERIPHERY OF THE CIRCULATION. 
UPPER LEVEL MOISTURE AND HIGH CLOUDS ARE OVER THE NW PORTION OF 
THE DISCUSSION AREA N OF 20N W OF 130W. THE REMAINDER OF THE 
AREA N OF 20N E OF 130W HAS STRONG SUBSIDENCE AND DRY/STABLE AIR.
OTHERWISE IN THE TROPICS S OF 20N BROAD UPPER RIDGE DOMINATES 
THE DISCUSSION AREA. UPPER LEVEL DIFFLUENT FLOW WITHIN THE RIDGE 
IS ENHANCING CONVECTIVE ACTIVITY FROM 5N TO 12N BETWEEN 102W AND 
120W.

1036 MB HIGH IS CENTERED NEAR 40N146W. A SURFACE HIGH PRES RIDGE 
IS N OF 15N W OF 120W. 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 
30N127W TO 26N140W. THIS WEATHER PATTERN AND CONDITIONS WILL 
PERSIST THROUGH LATE THU WITH INCREASING NLY SWELL ON THU. THE 
PRES GRADIENT ALONG THE SOUTHERN PERIPHERY OF THE RIDGE HAS 
DECREASED AND THE TRADES ARE LESS THAN 20 KT. THE MONSOON TROUGH 
HAS RECENTLY BEEN MOVED FURTHER W TO 122W DUE TO SCATTEROMETER 
WINDS SHOWING SW FLOW E OF 122W TO COLOMBIA.  

$$
FORMOSA