000
AXPZ20 KNHC 071538
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED OCT 07 2009

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1515 UTC.

...TROPICAL WAVE... 

A TROPICAL WAVE WAS ANALYZED ALONG 97W N OF 8N TO INLAND OVER S 
MEXICO MOVING W 20-25 KT. THE WAVE IS EMBEDDED WITHIN A BROAD 
AREA OF DEEP LAYER MOISTURE OBSERVED IN TOTAL PRECIPITABLE WATER 
IMAGERY. SCATTERED STRONG CONVECTION IS WITHIN 90/120 NM ALONG A 
LINE FROM THE WAVE AXIS NEAR 13N97W TO 17N102W INCLUDING PORTION 
OF THE MEXICAN COAST. SCATTERED MODERATE/ISOLATED STRONG 
CONVECTION IS WITHIN 120 NM ALONG THE COAST OF MEXICO S OF 20N W 
OF 102W AND WITHIN 90/120 NM OF LINE FROM THE WAVE AXIS NEAR 
15N97W TO 13N93W. 


...ITCZ...

THE ITCZ AXIS IS ALONG 7N77W 7N81W 12N95W 11N101W 8N121W 6N140W. 
A 1010 MB LOW IS EMBEDDED WITHIN THE ITCZ NEAR 11N112W BUT IS 
NOT PRODUCING ANY DEEP CONVECTION. SCATTERED MODERATE/ISOLATED 
STRONG CONVECTION IS FROM THE ITCZ TO 3N E OF 80W TO INLAND OVER 
COLOMBIA. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG 
CONVECTION COVER THE AREA FROM 5N TO THE ITCZ BETWEEN 97W-108W. 
CLUSTERS OF SCATTERED MODERATE CONVECTION DOT THE REMAINDER OF 
THE AREA WITHIN 200 NM EITHER SIDE OF THE ITCZ W OF 110W. 

...DISCUSSION...
A SURFACE TROUGH IS N OF THE ITCZ EXTENDING FROM 16N120W TO 
11N123W GENERATING SCATTERED/NUMEROUS STRONG CONVECTION WITHIN 
120 NM W OF THE TROUGH FROM 11N-14N WITH SCATTERED MODERATE/ 
ISOLATED STRONG CONVECTION WITHIN 120 NM W OF THE TROUGH FROM 
14N-16N AND FROM 10N-12N BETWEEN 124W-128W. 

AN UPPER LEVEL RIDGE COVERS THE E PACIFIC FROM 10N-23N BETWEEN 
90W-110W ANCHORED OVER CENTRAL MEXICO. UPPER RIDGE CONTINUES TO 
SHIFT EAST AND WEAKEN AHEAD OF A STRONG MID/UPPER LEVEL TROUGH 
EXTENDING FROM AN UPPER LOW OVER S/CENTRAL CALIFORNIA THROUGH 
30N120W TO 18N126W. 

SHIP AND SCATTEROMETER DATA INDICATE GENERALLY 15 TO 20 KT NW 
FLOW ALONG THE BAJA COAST...ON THE EASTERN PERIPHERY OF A 
SURFACE RIDGE AND IS EXPECTED TO CONTINUE THROUGH FRI. 

FURTHER SOUTH...THE 1010 MB LOW NOTED EMBEDDED WITHIN THE ITCZ 
IS EXPECTED TO DRIFT W TO SW OVER THE NEXT COUPLE OF DAYS. 
ALTHOUGH THIS LOW IS NOT PRODUCING ANY DEEP CONVECTION...IT MAY 
ENHANCE TRADE WIND FLOW AS IT INTERACTS WITH THE RIDGE TO THE 
NORTH. 

$$
WALLACE