000
AXPZ20 KNHC 252235
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC THU OCT 25 2007

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

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 2100 UTC.

...ITCZ....
AXIS ALONG 10N85W 11N106W 10N126W 11N132W 9N140W.
SCATTERED MODERATE CONVECTION WITHIN 30 NM OF AXIS E OF 92W.

...DISCUSSION...
UPPER TROUGH FROM 28N128W TO CYCLONIC VORTEX AT 22N129W 4N136W 
FOLLOWED DOWNSTREAM BY ANTICYCLONE GYRE AT 7N115W MAINTAIN A 
VERY DRY STABLE AIR MASS ACROSS ENTIRE E PAC W OF 105W.  SECOND 
UPPER LEVEL TROUGH ALONG 90W ALSO BRINGING DOWN DRY AIR MASS N 
OF 20N E OF 110W.  ONLY MOISTURE NOTED IS FROM 6N-20N E OF 110W. 

CARIBBEAN UPPER LEVEL RIDGE FORCED E BY SECOND TROUGH NOW KEEP 
ITS MOISTURE EAST F CENTRAL AMERICA AND FLORIDA.  

NEW LONGWAVE TROUGH ALOFT APPROACHES NW CORNER OF E PAC 
ADVECTING SOME MOISTURE BUT A JET CORE OF 70 KT TAKES IT NE
AWAY FROM BASIN.  WITH SO MUCH DRYNESS AROUND IT ITCZ KEEPS 
CONVECTION AT A MINIMUM. 

AT THE SFC...RIDGE EXTENDS SE FROM 1041 MB HIGH PRES WELL NW OF 
AREA TO 20N130W MAINTAINING STRONG NE TRADES AND LARGE LONG 
PERIOD SWELLS INTO E PAC THROUGH 48 HRS SPREADING S.  REMNANTS 
OF KIKO STILL SPINNING AT 19N121W BUT WINDS HAVE DECREASED 
SIGNIFICANTLY.

GAP WINDS...GALE WARNING REMAINS IN EFFECT ACROSS GULF OF 
TEHUANTEPEC.  GFS AND NAM GUIDANCE SUGGEST THAT EVENT SHOULD END 
IN ABOUT 18 HOURS.  HOWEVER...BOTH MODELS AGREE THAT WIND SHOULD 
REMAIN FAIRLY STRONG FOR THE NEXT COUPLE OF DAYS AND PERHAPS 
INCREASE BACK TO GALE FORCE BY END OF FORECAST PERIOD. 

$$
WALLY BARNES