000
AXPZ20 KNHC 280409
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC THU FEB 28 2008

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 
0345 UTC.
 
...ITCZ...
ITCZ-RELATED AXIS ALONG 6N77W 4N80W 2N99W 6N116W 5N130W 5N140W.  
SCATTERED MODERATE WITHIN 60 NM OF 8N135W AND 30 NM OF 9N114W.

...DISCUSSION...
DEEP LAYERED TROUGH FROM 32N131W TO 22N140W DIGS SE ACROSS WRN
E PAC BUT BEING BLOCKED S OF 20N BY PERSISTENT MID-UPPER LEVEL 
RIDGE WELL ANCHORED AT 11N123W.  S-SW WIND FLOW TOPPING 85 KT 
ADVECTING TRPCL MOISTURE FURTHER N INTO MID SECTION OF E PAC BUT 
1024 SURFACE HIGH PRES CENTERED AT 32N134W MAINTAINS TIGHT LID 
ON ANY CONVECTION TRYING TO SURVIVE.  SHORTWAVE TROUGH ALOFT 
DENTS RIDGE N OF 23N ALONG 120W BUT MODERATE TO STRONG 
SUBSIDENCE AND DRY AIR MASS RESTRAINS CLOUDINESS TO ONLY LOW 
LEVELS.

MODELS SHOW WEAK TROUGH ALOFT APPROACHING NRN BAJA CALIFORNIA 
BUT LACKS MOISTURE TO GET ANYTHING STARTED.  MODERATE 
SUBSIDENCE UNDER BROAD UPPER RIDGING S OF 9N FROM 90W-120W.

AT THE SURFACE...HIGH PRES MENTIONED ABOVE HAS RIDGE STRETCH SE 
N OF 15N W OF 115W.

GULF OF TEHUANTEPEC STORM WARNING APPEARS ON VERGE OF VERIFYING 
TONIGHT AS QUIKSCAT AND SHIP REPORTS INDICATE STRONG GALE AND IT 
IS YET TO PEAK.  MODEL GUIDANCE FORECASTS WINDS TO INCREASE TO 
STORM FORCE IN ABOUT 6 HRS...AND LAST THROUGH THU...THEN SUBSIDE 
TO GALE FORCE AGAIN FRI MORNING.

GULF OF PANAMA AND PAPAGAYO GAP WIND INCREASING AS CARIBBEAN 
RIDGE PRESSES AGAINST 1006 MB LOW PRES CENTER OVER COLOMBIA.

$$
WALLY BARNES