000
AXPZ20 KNHC 031513
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SUN MAY 03 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 
1500 UTC.

...ITCZ...
AXIS IS ALONG 7N78W 5N110W 6N105W 4N115W 07N125W 5N140W. 
SCATTERED MODERATE ISOLATED STRONG CONVECTION WITHIN 60 NM 
EITHER SIDE AXIS E OF 80W AND WITHIN 120 NM N OF AXIS FROM 
96W-110W. SCATTERED MODERATE TO STRONG CONVECTION WITH 60 NM 
RADIUS OF 9N131W.

...DISCUSSION...
UPPER LEVEL CYCLONIC CIRCULATION IS CENTERED NEAR 19N132W WITH A 
TROUGH FROM THE CYCLONIC CIRCULATION SW TO 12N140W. STRONG 
SUBSIDENCE WITH DRY STABLE AIR IS S OF 25N W OF THE TROUGH. A 
40-50 KT WIND MAX IS E OF THE TROUGH AXIS FROM 11N135W TO 
23N128W. BROKEN TO OVERCAST MID AND HIGH CLOUDS AREA WITHIN
300 NM SE OF THE WIND MAX. UPPER LEVEL ANTICYCLONIC CIRCULATION 
IS E OF THE TROUGH NEAR 19N119N...WITH RIDGE EXTENDING FROM THE 
ANTICYCLONIC CIRCULATION TO THE CENTRAL BAJA PENINSULA INTO NW 
MEXICO. UPPER LEVEL TROUGH WITH AXIS FROM NEAR BROWNSVILLE TEXAS 
ACROSS MEXICO TO 20N117W. HIGH CLOUDS ARE WITHIN 180 NM E OF THE 
TROUGH.

AN ELONGATED UPPER LEVEL CYCLONIC CIRCULATION IN THE DEEP 
TROPICS IS CENTERED NEAR 10N104W...WITH TROUGH EXTENDING FROM 
THE CIRCULATION S TO THE EQUATOR AT 105W. SW FLOW E OF THE 
CYCLONIC CIRCULATION IS ADVECTING MOISTURE FROM ITCZ CONVECTION 
INTO CENTRAL AMERICA FROM GUATEMALA TO NICARAGUA. UPPER LEVEL 
ANTICYCLONIC CIRCULATION IS CENTERED NEAR 9N86W. DIFFLUENT FLOW 
ALOFT WITH THE ANTICYCLONIC CIRCULATION IS ENHANCING CONVECTIVE 
ACTIVITY ALONG THE COASTS OF COSTA RICA AND PANAMA. 

A 1025 MB SURFACE HIGH PRES IS CENTERED NEAR 29N129W WITH RIDGE 
COVERING THE AREA N OF 15N W OF 110W. THE HIGH IS BLOCKING A
SERIES OF COLD FRONTS TO N OF 30N...HOWEVER NW SWELLS TO 10 FT 
WILL SPREAD SE INTO THE NW PORTION OF THE AREA IN ABOUT 24 
HOURS. ALSO THE HIGH COMBINED WITH LOWER PRES OVER MEXICO IS 
CONTINUING TO PRODUCE 20 KT NW WINDS OFF THE COAST OF BAJA 
CALIFORNIA. A 1011 MB LOW PRES IS CENTERED JUST N OF THE ITCZ 
NEAR 7N90W. SCATTERED SHOWERS ARE WITHIN 100 NM NW SEMICIRCLE.
SURFACE TROUGH IS ANALYZED ALONG THE ITCZ FROM 10N124W TO 3N125W.
ISOLATED SHOWERS ARE ALONG THE TROUGH.

$$
DGS