000
AXPZ20 KNHC 210322
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC MON AUG 20 2007

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0245 UTC.

...TROPICAL WAVE...

TROPICAL WAVE IS ALONG 100W N OF 4N MOVING W 15 KT. LITTLE 
SIGNATURE IS SEEN ON SATELLITE IMAGERY ALONG THE AXIS...BUT 
THERE IS AN WEAK SLIGHTLY CURVED BAND FEATURE SEEN FURTHER TO 
THE W NEAR 107W. FOR NOW...THE FEATURE ALONG 107W IS ANALYZED AS 
A TROUGH SINCE IT WAS DIFFICULT TO CONFIRM IF THIS WAVE MOVED 
THAT FAR. CONVECTION IS MINIMAL NEAR THE WAVE AT THE MOMENT. 
THERE IS A WEAKENING AREA OF SCATTERED MODERATE WITHIN 60 NM W 
OF THE TROUGH AXIS.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 9N80W 8N105W 10N110W 13N120W 
11N140W. SCATTERED MODERATE WITHIN 150 NM S OF AXIS E OF 86W AND 
FROM 15N TO 17N BETWEEN 116W AND 118W.

...DISCUSSION...

AN UPPER LEVEL RIDGE...CENTERED ABOVE THE NRN PORTION OF BAJA 
CALIFORNIA...CONTROLS THE UPPER PATTERN ACROSS THE SUBTROPICS 
OUT TO 135W. WEAK INVERTED TROUGHING LIES W OF THERE ASSOCIATED 
WITH AN UPPER LOW CENTERED NEAR 16N138W. A FAIR AMOUNT OF HIGH 
LEVEL CLOUDS ARE LOCKED IN THE RIDGE...BUT IR IMAGERY DOES NOT 
SUGGEST MUCH PRECIP. CONFLUENCE ALOFT IS STABILIZING THE 
ATMOSPHERE ACROSS THE W PORTION OF THE AREA SUPPRESSING ANY DEEP 
OR HIGH LEVEL CLOUDINESS. MOISTURE IS A BIT MORE CONCENTRATED IN 
THE TROPICAL E PORTION OF THE AREA...BUT NEARLY ALL OF THE 
CONVECTION IS EMBEDDED WITHIN THE ITCZ. 

IN THE LOWER LEVELS...THE MAIN FEATURE IS A WEAKENING 1010 MB 
LOW CENTERED NEAR 25N120W. THIS SYSTEM HAS NOW MOVED OVER COOL 
WATERS AND CONSISTS OF ONLY LOW CLOUDS SWIRLING ABOUT IT'S 
CENTER. QSCAT AND ASCAT MISSED THE CIRCULATION...BUT BASED ON 
PREVIOUS DATA A SMALL AREA OF 20 KT WINDS ARE STILL POSSIBLE IN 
THE SE SEMICIRCLE...THOUGH NOT EXPECTED TO LAST MUCH LONGER. 
ELSEWHERE...BROKEN STRATOCUMULUS CLOUDS ARE THE MAIN SOURCE OF 
CLOUD COVER ACROSS THE SUBTROPICAL BELT INDICATING THE STABILITY 
ACROSS THE AREA. THE OVERALL WEAK PRES PATTERN IN PLACE IS 
KEEPING TRADE WINDS ON THE LIGHT SIDE.  

$$
CANGIALOSI