000
AXPZ20 KNHC 222201
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SUN APR 22 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2115 UTC.

...ITCZ...
ITCZ AXIS ALONG 7N77W  8N82W  6N88W  9N93W  7N102W  8N111W  
5N126W  5N140W.  SCATTERED MODERATE ISOLATED STRONG FROM 103W TO 
113W AND W OF 133W.  ISOLATED MODERATE E OF 89W FROM 4N TO 8N.  

...DISCUSSION...
SHORTWAVE TROUGH OVER SRN CALIFORNIA AT 32N116W EXTENDS SWWD 
INTO DISCUSSION AREA TO 20N124W AND CONTINUE W TO 20N140W.  VERY 
DRY AIR MASS ALOFT WITHIN 180 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 100 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 97W LITERALLY SHUTTING DOWN ITCZ 
CONVECTION TO MINOR BURST NEAR 5N87W AND 10N92W AS UPPER LEVEL 
DEFORMATION ZONE ALLOWS MINOR DIFFLUENCE ABOVE.  

AT THE SFC...STATIONARY 1026 MB HIGH PRES CENTER ANALYZED AT 
29N147W 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