000
AXPZ20 KNHC 040250
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC MON AUG 04 2008

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 
0230 UTC.

...TROPICAL WAVES... 

TROPICAL WAVE IS LOCATED FROM THE ISTHMUS OF TEHUANTEPEC 
SOUTHWARD ALONG 95W N OF 07N MOVING W 15-20 KT. THE WAVE IS NOT 
PARTICULARLY WELL-DEFINED BUT IS PLACED NEAR A MID-LEVEL 
CIRCULATION NOTED WITHIN CONVECTION ALONG THE ITCZ. SCATTERED 
MODERATE CONVECTION IS MOVING WESTWARD ACROSS PORTIONS OF 
GUATEMALA AND SE MEXICO TOWARDS THE COASTAL WATERS OF THE GULF 
OF TEHAUNTEPEC. OTHERWISE...WEAKER CONVECTION IS NOTED ALONG THE 
ITCZ.

TROPICAL WAVE IS ALONG 109W/110W S OF 17N MOVING W 10-15 KT. 
CONFIDENCE IN THE POSITION OF THIS WAVE IS QUITE LOW DUE TO THE 
EXISTENCE OF SEVERAL LOW-LEVEL CIRCULATIONS ALONG THE ITCZ. IN 
FACT...THE WAVE HAS MOVED PAST A FAIRLY WELL-DEFINED STATIONARY 
1008 MB LOW LOCATED ALONG THE ITCZ NEAR 08N104W. ONLY SCATTERED 
SHOWERS/TSTMS ARE NEAR THE WAVE WITHIN THE ITCZ.

...ITCZ...

ITCZ AXIS IS CENTERED FROM 10N85W TO 09N110W TO 10N128W TO 
09N140W. SCATTERED MODERATE CONVECTION FROM 04N-10N BETWEEN 
86W-90W. SCATTERED MODERATE FROM 06N-14N BETWEEN 96W-108W. 
SCATTERED MODERATE/ISOLATED STRONG FROM 07N-13N W OF 130W.

...DISCUSSION...

E OF 120W...
A LARGE BLOCKING MID/UPPER RIDGE IS LOCATED ACROSS THE S/CENTRAL 
UNITED STATES WITH PREDOMINANTLY DEEP EASTERLY FLOW AROUND 
SYSTEM ACROSS MUCH OF MEXICO AND THE ADJACENT WATERS. THE RIDGE 
IS BOUNDED BY A VIGOROUS UPPER LOW OVER THE NW CARIBBEAN NEAR 
19N85W AND A MID/UPPER TROUGH JUST SW OF BAJA CALIFORNIA ALONG 
118W N OF 10N. DEEP-LAYERED MOISTURE DOMINATES MUCH OF THIS 
REGION...AND SOUTHEASTERLY FLOW AROUND THE PERIPHERY OF THE 
RIDGE HAS EVEN ADVECTED THE MOISTURE NWD THROUGH THE GULF OF 
CALIFORNIA AND ACROSS BAJA CALIFORNIA. THIS MOISTURE HAS 
RESULTED IN WIDESPREAD TSTM DEVELOPMENT ACROSS THE SIERRA MADRE 
OCCIDENTALS OF WESTERN MEXICO INTO THE U.S. ROCKIES. AS NOTED 
ABOVE...A 1008 MB NEARLY STATIONARY LOW IS LOCATED ALONG THE 
ITCZ NEAR 08N104W AND IS EXPECTED TO MOVE VERY LITTLE UNTIL THE 
TROPICAL WAVE NEAR 95W BEGINS TO INTERACT WITH IT IN ANOTHER 48 
HOURS OR SO. ELSEWHERE...THE AREA OF LOW PRES WHICH WAS LOCATED 
NEAR THE BAJA PENINSULA HAS WEAKENED WITH NO NOTICEABLE 
SIGNATURE RECOGNIZED IN THE NEARBY CLOUD FIELD.

W OF 120W...
A STRONG MID/UPPER LEVEL RIDGE DOMINATES THE NW PORTION OF THE 
AREA FROM 30N122W SW PAST 22N140W AND IS PRODUCING 
MODERATE/STRONG SUBSIDENCE N OF 16N W OF 125W. A BROKEN 
STRATOCUMULUS FIELD LIES BENEATH THIS SUBSIDENCE MOVING S/SW 
AROUND THE SUBTROPICAL RIDGE. FARTHER S...THE ITCZ IS 
CONVECTIVELY ACTIVE W OF 130W DUE TO STRONG LOW-LEVEL 
CONVERGENCE AND FAVORABLE OUTFLOW TO THE S.

$$
BERG