000
AXPZ20 KNHC 041503
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC TUE MAY 04 2010

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

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

...ITCZ...
AXIS IS ALONG 8N83W 4N95W 6N105W 4N115W 6N140W. SCATTERED 
MODERATE ISOLATED STRONG CONVECTION WITHIN 120 NM EITHER SIDE 
OF AXIS FROM 83W TO 87W AND WITHIN 200 NM EITHER SIDE OF AXIS 
FROM 95W TO 101W.

...DISCUSSION...
AN UPPER LEVEL SHORTWAVE TROUGH IS APPROACHING THE EXTREME NW
PORTION OF THE DISCUSSION AREA...OTHERWISE AN UPPER LEVEL RIDGE
COVERS THE AREA N OF 15N W OF 130W. THE RIDGE AXIS EXTENDS FROM
32N130W TO 15N140W. HIGH LEVEL MOISTURE IS LOCATED ON THE W SIDE
OF THE RIDGE. AN UPPER LEVEL TROUGH WITH AXIS EXTENDING FROM 
SOUTHERN CALIFORNIA INTO THE DISCUSSION AREA NEAR 32N122W TO 
15N1267W TO 00N126W. MODERATE TO STRONG SUBSIDENCE WITH DRY 
STABLE AIR AT THE MIDDLE AND UPPER LEVELS OF THE ATMOSPHERE 
COVERS THE AREA BETWEEN THE RIDGE AND TROUGH AXIS.

A BROAD UPPER LEVEL ANTICYCLONIC CIRCULATION CENTERED OVER S 
CENTRAL MEXICO NEAR 20N101W WITH RIDGE FROM THE ANTICYCLONE TO 
15N110W 10N115W. E PACIFIC ITCZ CONVECTION IS BEING ENHANCED 
UNDER THIS RIDGE FROM COSTA RICE W TO 101W.

AN UPPER LEVEL CYCLONIC CIRCULATION IS CENTERED IN THE W 
CARIBBEAN AND IS MOVING SLOWLY TO THE W WITH AN UPPER LEVEL 
TROUGH ACROSS NICARAGUA TO NEAR 8N90W. VERY DRY AIR IS NOTED N 
OF 15N E OF 115W.

SURFACE RIDGE DOMINATES THE DISCUSSION AREA N OF 10N W OF 110W.  
NE TRADES ALONG THE SOUTHERN PERIPHERY OF THE RIDGE ARE AT 15-20 
KT WITH SEAS 8-10 FT. A SURFACE TROUGH IS ANALYZED ALONG THE ITCZ
FROM 10N104W TO 3N106W. SCATTERED MODERATE CONVECTION IS WITHIN
120 NM E OF THE TROUGH AXIS FROM 4N-7N.

$$
DGS