000
AXPZ20 KNHC 282205
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON MAY 28 2007

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.

...SPECIAL FEATURES...

TROPICAL DEPRESSION ONE-E AT 12.8N 113.2W AT 2100 UTC WITH 
ESTIMATED CENTRAL PRES OF 1005 MB MOVING W OR 260 DEG AT 5 KT. 
NUMEROUS MODERATE TO STRONG WITHIN 90 NM SW SEMICIRCLE OF CENTER.
FAVORABLE WATER TEMPERATURES SUPPORT THE FORECAST FOR CONTINUED 
DEVELOPMENT TO A TROPICAL STORM MOVING W UNDER AN UPPER RIDGE. 

...ITCZ...

INTERTROPICAL CONVERGENCE ZONE AXIS 11N85W 13N97W 9N102W 7N140W. 
SCATTERED MODERATE ISOLATED STRONG WITHIN 120 NM 11N86W 12N99W 
AND LINE 7N103W 11N110W AND WITHIN 8N125W.

...DISCUSSION...

A WELL DEFINED UPPER ANTICYCLONE HAS SHIFTED E TO NEAR 14N108W.
A SECOND UPPER ANTICYCLONE IS NEAR 9N135W. THE COMBINED RIDGE 
CRESTS ALONG POINTS 18N140W 29N124W 24N109W. AN UPPER TROUGH IS 
OBSERVED NW OF THE RIDGE ALONG 32N120W 30N135W THEN SW TO BEYOND 
23N140W. UPPER MOISTURE IS INDICATED ALONG A PLUME ALONG THE 
RIDGE CREST WITHIN 120 NM EITHER SIDE OF LINE 14N140W 22N130W 
25N117W. OTHER DRY UPPER AIR IS TRAPPED UNDER THE UPPER RIDGE 
AND EFFECTIVELY SUPPRESSES CONVECTION ALONG THE ITCZ BETWEEN 
128W AND 137W. ITCZ CONVECTION AND IS ENHANCED BETWEEN 93W AND 
118W. SOME OF THE RESULTANT DEBRIS MOISTURE IS ADVECTED S ACROSS 
THE EQUATOR BETWEEN 107W AND 119W. SOME OF THE MOISTURE SPREADS 
N BUT EVAPORATES IN THE UPPER DRY AIR ALONG 20N.  

AN UPPER TROUGH EXTENDS S ACROSS OLD MEXICO ALONG 24N99W TO 
18N99W. ANOTHER UPPER ANTICYCLONE IS NEAR 13N96W WITH A RIDGE E 
ACROSS CENTRAL AMERICA.

AT THE SURFACE...
WEAK HIGH PRES CENTER 1026 MB AT 35N134W HAS RIDGE EXTENDING SE 
TO NEAR 21N109W. 

$$
NELSON