000
AXPZ20 KNHC 230329
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC MON APR 23 2007

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0345 UTC.

...ITCZ...
ITCZ AXIS ALONG 5N77W  5N86W  9N94W  6N106W  5N138W  4N140W.  
ISOLATED MODERATE FROM 101W TO 112W AND W OF 132W.

...DISCUSSION...
SHORTWAVE TROUGH OVER SRN CALIFORNIA AT 32N114W EXTENDS SWWD 
INTO DISCUSSION AREA TO CYCLONIC VORTEX AT 20N129W THEN CONTINUE 
W TO 19N140W.  VERY DRY AIR MASS ALOFT WITHIN 210 NM OF TROUGH 
AXIS DUE TO MODERATE TO STRONG SUBSIDENCE.  UPSTREAM RIDGE 
FOLLOWS BEHIND WITH MOISTURE ADVECTED INTO BASIN N OF 25N W OF 
TROUGH.  PLENTY OF WATER ADVECTED BY 105 KT SUBTROPICAL JET CORE 
SE OF TROUGH AXIS INTO SRN HALF OF BAJA CALIFORNIA AND NW MEXICO 
BUT REGION IS UNDER LOW LEVEL HIGH PRES RIDGE WITH LITTLE UPLIFT 
MECHANISM TO PROMPT SIGNIFICANT PRECIPITATION.  

DOWNSTREAM...UPPER LEVEL RIDGE THAT DOMINATES ENTIRE CARIBBEAN 
BASIN EXTENDS INTO E PAC LITERALLY SHUTTING DOWN ITCZ CONVECTION 
TO MINOR BURST NEAR 8N102W AS UPPER LEVEL DEFORMATION ZONE 
ALLOWS MINOR DIFFLUENCE ABOVE.  

AT THE SFC...STATIONARY 1025 MB HIGH PRES CENTER ANALYZED AT 
28N145W WITH RIDGE EXTENDING ESE THROUGH 21N113W AND CONTROLLING 
CONVECTION N OF 15N W OF 112W.  HIGH PRES MAINTAINS STRONG NE 
TRADES FROM 6N-21N W OF 130W BUT SHOULD DIMINISH AS RIDGE DRIFTS 
E AND WEAKENS.  WINDS ALONG BAJA CALIFORNIA ALSO EXPECTED TO 
DIMINISH AS WEAK COLD FRONT ERODES HIGH PRES GRIP ON E PAC.
WEAK TRADES CROSS CENTRAL AMERICA NEAR GULF OF PAPAGAYO WITHIN 
NEXT 24 HRS.

$$
WALLY BARNES