000
AXPZ20 KNHC 191005
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC TUE FEB 19 2008

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

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0930 UTC.
 
...ITCZ...
ITCZ AXIS ALONG...5N77W  8N123W  6N140W.  SCATTERED MODERATE 
CONVECTION WITHIN 180 NM N AND 75 NM S OF AXIS FROM 117W TO 128W 
AND WITHIN 90 NM OF AXIS E OF 88W. 

...DISCUSSION...
LARGE AMPLITUDE UPPER LEVEL TROUGH EXTENDS FROM 32N117W TO 
12N140W ALLOWING COOL DRY AIR MASS TO DIG DEEP INTO TROPICS 
ALONG 90 KT JTST OF W SIDE.  BROAD MID-UPPER LEVEL RIDGE 
DOWNSTREAM FROM TROUGH...EXTENSION OF ANTICYCLONIC CENTER 
LOCATED OVER VENEZUELA...IS ADVECTING WARM MOIST TROPICAL AIR 
MASS NE INTO BAJA CALIFORNIA RIDING ON 95 KT SUBTROPICAL JTST.  
DIFFLUENT FLOW BETWEEN BOTH FEATURES ENHANCING SCATTERED DEEP 
CONVECTION ALONG 124W.  WEAK UPPER LEVEL TROUGH CUTS SW ACROSS 
SRN MEXICO TO 17N100W TO 11N107W DENTS NW CORNER OF RIDGE.      
  
GFS MODEL HAS THE LARGE AMPLITUDE UPPER LEVEL TROUGH STALL FROM 
32N103W TO 1N140W WITHIN 48 HRS AS RIDGE REBUILDS AND FLATTEN 
THE WEAK TROUGH DENTING IT AND RECOVERS ITS WESTERNMOST 
EXTENSION.  THIS SHOULD EFFECTIVELY STALL COLD FRONT ASSOCIATED 
WITH THE MAIN TROUGH ALONG NRN WATERS OF E PAC BASIN AND 
REINFORCE DOMINANT SURFACE HIGH PRES 1024 MB RIDGE LOCATED AT 
27N126W.  

SURFACE...
SURFACE HIGH PRES MAINTAINS BRISK TRADES FROM 9N-15N W OF 130W 
THROUGH FORECAST PERIOD...BUT STALLING COLD FRONT LIKELY TO 
USHER LONG PERIOD SWELLS...BUILDING AS HIGH AS 12 FT...INTO W 
HALF OF BASIN. 

HIGH PRES RIDGE REBUILDING OVER WRN CARIBBEAN WILL INCREASE 
WINDS SPILLING INTO E PAC THROUGH GULF OF PAPAGAYO WITHIN  NEXT 
24 HRS.

$$
WALLY BARNES