000
AXPZ20 KNHC 272152
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON JUL 27 2009

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

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2145 UTC.

...TROPICAL WAVES...
A TROPICAL WAVE EXTENDS FROM 04N TO 13N ALONG 106W AND HAS BEEN 
MOVING W AT AN ESTIMATED 15 KT. SCATTERED MODERATE AND ISOLATED 
STRONG CONVECTION IS CURRENTLY ENHANCED FROM 08N TO 15N BETWEEN 
105W AND 109W. 

A TROPICAL WAVE FROM 04N TO 17N ALONG 123W HAS MOVED W AROUND 15 
KT. THE WAVE IS MOVING UNDER AN UPPER RIDGE WITH THE ASSOCIATED 
DIFFLUENCE ENHANCING A LARGE AREA OF SCATTERED MODERATE AND 
ISOLATED STRONG CONVECTION OVER THE PACIFIC FROM 07N TO 15N 
BETWEEN 120W AND 128W. 

A TROPICAL WAVE EXTENDS FROM 04N TO 12N ALONG 131W AND HAS MOVED 
W AT ABOUT 13 KT OVER THE PAST 24 HOURS. THE WAVE IS MOVING 
THROUGH AN AREA THAT HAS SOMEWHAT UNFAVORABLE UPPER SUPPORT WITH 
CONVECTION SUPPRESSED N OF 10N BUT ENHANCED FROM 06N TO 10N 
BETWEEN 119W AND 132W. 

...ITCZ...
THE AXIS EXTENDS ALONG POINTS FROM 09N76W TO 06N82W TO 11N105W 
T0 11N120W TO 07N140W. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION IS NOTED WITHIN 90 NM OF 05N81W AND ALSO WITHIN 270 
NM OF LINE FROM 17N100W TO 06N139W.

...DISCUSSION...
AN UPPER LEVEL RIDGE POKES E INTO THE SW CORNER ALONG 09N W OF 
136W. A MID TO UPPER LEVEL CYCLONE N OF THE AREA IS NEAR 36N138W 
WITH A TROUGH S ALONG 32N139W TO A BASE AT 14N136W. CYCLONIC 
FLOW DOMINATES THE UPPER LEVELS N OF 16N W OF 125W WITH DEBRIS 
MOISTURE INDICATED N OF 25N W OF 130W...WHILE DRY AIR IS 
OBSERVED ELSEWHERE WITHIN THE TROUGH. 

AN UPPER ANTICYCLONE IS CENTERED OVER NORTHWESTERN OLD MEXICO AT 
29N110W WITH ITS ANTICYCLONIC CIRCULATION DOMINATING THE AREA N 
OF 22N BETWEEN 100W AND 120W. AN UPPER TROUGH EXTENDS SW ACROSS 
CENTRAL AMERICA INTO THE PACIFIC ALONG 20N99W TO 10N107W TO 
01N110W. CONVECTION IS ENHANCED OVER THE AREA FROM 10N TO 18N 
BETWEEN 98W AND 110W WITH THE DEBRIS MOISTURE ADVECTED NE ACROSS 
THE GULF OF MEXICO AND FLORIDA. 

AN UPPER ANTICYCLONE HAS FORMED NEAR 15N120W AND IS ENHANCING 
CONVECTION BETWEEN 113W AND 132W. AN UPPER CYCLONE IS OVER THE 
DEEP TROPICS AT 07N87W AND IS MOVING W WITH TIME. 
   
GAP WINDS...NE TO E WINDS IN AND DOWNSTREAM OF THE GULF OF 
PAPAGAYO ARE EXPECTED TO CONTINUE FOR AT LEAST A COUPLE MORE 
DAYS. 

$$
NELSON