000
AXPZ20 KNHC 111516
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SUN MAY 11 2008

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 
1200 UTC.

...ITCZ...
ITCZ AXIS CENTERED ALONG 07N78W TO 08N115W TO 06N125W TO 
05N140W. SCATTERED MODERATE TO STRONG WITHIN 90 NM S OF AXIS 
FROM 78W TO 80W AND WITHIN 200 NM S OF AXIS FROM 102W TO 105W. 
SCATTERED MODERATE ISOLATED STRONG WITHIN 60 NM EITHER SIDE OF 
AXIS FROM 131W TO 134W.

...DISCUSSION...
MID/UPPER LEVEL CYCLONIC CIRCULATION CENTERED NEAR 29N128W IS 
DRIFTING TO THE NE. TROUGH EXTENDING FROM 32N126W THROUGH THE 
CYCLONIC CIRCULATION TO 22N138W. MODERATE TO STRONG SUBSIDENCE 
WITH ASSOCIATED DRY AIR ALOFT COVERS THE AREA FROM 24N-30N W OF 
122W. A 95 KT SUBTROPICAL JET STREAM SE OF THE TROUGH FROM 
17N140W 20N125W TO CENTRAL BAJA CALIFORNIA. THE JET IS ADVECTING 
TROPICAL MOISTURE INTO SOUTHERN BAJA CALIFORNIA AND NW MEXICO.  

BROAD ANTICYCLONE OVER THE BAY OF CAMPECHE WITH RIDGE EXTENDING 
NW ACROSS MEXICO AND INTO THE SOUTHERN ROCKIES. VERY DRY AIR 
MASS UNDER RIDGE DUE TO MODERATE TO STRONG SUBSIDENCE ACROSS 
MUCH OF MEXICO AND GUATEMALA FROM 15N-23N E OF 110W. TAIL END OF 
UPPER LEVEL LONG WAVE TROUGH WITH AXIS FROM THE SW CARIBBEAN
ACROSS PANAMA. DIFFLUENT FLOW OVER THE SOUTHERN PORTION OF THE 
TROUGH IS ENHANCING CONVECTIVE ACTIVITY OVER PANAMA AND COSTA 
RICA.

A COUPLE OF TROUGHS ARE ANALYZED ALONG THE ITCZ...ONE FROM 12N-4N
ALONG 93W WITH SCATTERED SHOWERS AND TSTMS FROM 7N-14N BETWEEN
89W-96W. ANOTHER TROUGH FROM 14N-6N ALONG 113W. SCATTERED SHOWERS
AND A FEW TSTMS ARE WITHIN 150 NM EITHER SIDE OF TROUGH. HIGH 
PRES RIDGE EXTEND FROM 32N140W TO 17N106W. BROKEN/OVERCAST 
STRATOCUMULUS CLOUDS COVER THE AREA N OF 13N W OF 120W AND N OF 
23N E OF 120W.

$$
DGS