000
AXPZ20 KNHC 301620
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SAT AUG 30 2008

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1445 UTC.

...TROPICAL WAVES...
TROPICAL WAVE ALONG 106W FROM 10N-17N MOVING W 10 KT HAS 
MODERATE TO STRONG SHEAR ALOFT N OF ITCZ INHIBITING ITS 
DEVELOPMENT.  WAVE TRAVELING ALONG SRN PERIPHERY OF BROAD UPPER 
LEVEL ANTICYCLONE CENTERED AT 22N118W.  THESE CONDITIONS LIKELY 
EXTENDING TO 130W LIMITING CHANCES OF CYCLONIC ORGANIZATION OF 
WAVE.  SCATTERED MODERATE CONVECTION IS SEPARATING FROM WAVE 
AXIS.
     
...ITCZ...
ITCZ AXIS ALONG 09N78W TO 12N100W TO 12N120W TO 08N140W. 
SCATTERED MODERATE ISOLATED STRONG CONVECTION WITHIN 150 NM OF 
LINE 05N79W TO 07N88W AND WITHIN 240 NM OF LINE 16N102W TO 
07N122W.

...DISCUSSION...
LARGE AMPLITUDE TROUGH ENTER E PAC AT 140W EXPECTED TO SHIFT NE 
AS BROAD ANTICYCLONE AT 22N118W WILL BLOCK ANY FURTHER EWD 
INTRUSION.  AIR MASS REMAINS VERY DRY N OF 17N W OF 109W DUE TO 
MODERATE TO STRONG SUBSIDENCE UNDER ANTICYCLONE.

PLENTY OF TROPICAL MOISTURE ADVECTING ALONG SRN FRINGES OF UPPER 
LEVEL ANTICYCLONE WITH ITCZ MAKING GOOD USE OF IT FOR SCATTERED 
MODERATE CONVECTION E OF 88W AND FROM 100W-122W.  LACK OF 
UPLIFTING MECHANISMS AND ADVERSE UPPER ENVIRONMENT PREVENT 
DEEPER CONVECTION FROM FORMING.

ELSEWHERE AT THE SURFACE...
HIGH PRES 1033 MB AT 44N150W BEHIND COLD FRONT WELL N OF AREA 
ALONG 36N FROM 130W TO 140W.  COMPLEX LOW PRES SYSTEM OVER NRN 
CALIFORNIA PRODUCING GALE WINDS WELL N OF AREA BUT SOME 20 KT 
EXTEND S INTO E PAC WITH 8-12 FT SEAS. 

CROSS EQUATORIAL SWELL MOVING INTO E PAC S OF 10N OBSERVED TO BE 
1-2 FT UNDER NWW3 GUIDANCE.  SWELL TO CONTINUE THROUGH FORECAST 
PREIOD.  

$$
WALLY BARNES