000
AXPZ20 KNHC 220322
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC FRI MAY 22 2009

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

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0300 UTC.

...ITCZ...
AXIS ALONG 07N78W TO 10N93W TO 09N103W TO 13N120W TO 05N140W.  
SCATTERED MODERATE TO STRONG CONVECTION WITHIN 120 NM N AND 300 
NM S OF AXIS FROM 106W TO 123W.  SCATTERED MODERATE CONVECTION 
WITHIN 150 NM N OF AXIS FROM 135W TO 138W.

DISCUSSION...
MID/UPPER E-W RIDGE WITH AXIS BETWEEN 09N-12N STRETCHES E OF 
128W MAINTAINING GOOD OUTFLOW OVER ITCZ AND ENHANCING CONVECTION 
CAUSED BY TWO SURFACE LOW PRES CENTERS...ONE AT 13N121W WITH 
1008 MB AND A SECOND ONE AT 12N110W...ALSO 1008 MB.  VERY DRY 
QUASI-ZONAL JET CORE OF 85 KT FLOW ALOFT N OF 20N W OF 105W NOT 
ALLOWING ANY MOISTURE INTO ITS BOUNDARIES.  ITCZ CONVECTION 
DEBRIS FOLLOW RIDGE NORTHERN PERIPHERY S OF 20N FLOWING E INTO 
NORTHWESTERN CARIBBEAN FEEDING AREA OF STRONG UPPER DIFFLUENCE 
...HENCE ABUNDANT DEEP CONVECTION IN THAT BASIN.

WESTERNMOST LOW PRES MENTIONED ABOVE UNDER INCREASINGLY 
UNFAVORABLE UPPER ENVIRONMENT SHOULD WEAKEN AND DISSIPATE BY 
FRI.  EASTERNMOST LOW PRES CENTER REMAINS CLOSE TO ANTICYCLONE 
ALOFT AT 10N105W AND IS EXPECTED TO PRODUCE FRESH TO STRONG 
BREEZE THROOUGH SAT. 

ELSEWHERE AT THE SURFACE...
HIGH PRES CENTER 1032 MB WELL N OF BASIN HAS RIDGE EXTEND SE TO 
15N110W PRODUCING FRESH TRADES WITH 8 FT SEAS W OF 123W.  SYSTEM 
COMBINES WITH LOW PRES CENTER 1002 MB OVER NORTHERN CALIFORNIA 
TO PRODUCE GALE FORCE WINDS ALONG COAST OF CALIFORNIA SPILLING N 
SWELLS SPREADING INTO E PAC N OF 28N WITHIN 30 HRS.  

$$
WALLY BARNES