000
AXPZ20 KNHC 271550
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC TUE MAY 27 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 
1415 UTC.

...TROPICAL WAVES...
NONE.

...ITCZ...
INTERTROPICAL CONVERGENCE ZONE ALONG 09N83W TO 05N93W TO 08N135W 
TO 07N140W.  SCATTERED MODERATE/ ISOLATED STRONG CONVECTION 
WITHIN 120 NM S OF AXIS FROM 103W-113W AND S OF AXIS TO 02N E OF 
90W.

...DISCUSSION...
MID/UPPER LEVEL TROUGH EXTENDS SWD ACROSS NW CORNER OF E PAC 
FROM CYCLONIC VORTEX AT 36N123W TO 21N140W.  TROUGH FORECAST TO 
MOVE SE AND LIFT NE OF REGION THU AS BROAD RIDGE ANTICYCLONIC 
CENTER IS WELL ANCHORED AT 21N104W BLOCKING ANY FURTHER SE 
INTRUSION.  UPPER LEVEL MOISTURE RESTRICTED TO AREA N OF 27N W 
OF 120W WHILE MODERATE TO STRONG SUBSIDENCE UNDER RIDGE DRIES 
OUT AIR MASS CURTAILING CLOUD DEVELOPMENT EVEN INTO ITCZ W OF 
120W.  

UPPER RIDGE PROVIDES GOOD UPPER DIFFLUENCE AND OUTFLOW FOR ITCZ 
DEEP CONVECTION E OF 95W BUT LACK OF UPLIFTING MECHANISM 
PREVENTS CONTINUITY TO CYCLE.  ONLY EXCEPTION TO THIS SCENARIO 
IS HEALTHY 1008 MB LOW PRES AT 11N91W.  WHILE STILL QUASI- 
STATIONARY...LOW PRES IS EXPECTED TO DRIFT INTO FAVORABLE 
ENVIRONMENT ALOFT CONDUCIVE TO DEVELOPMENT WITHIN 48 HRS AS 
LARGE AREA OF WLY WINDS ON S SIDE OF LOW PRES LIKELY TO BRING 
PLENTY OF ADDITIONAL WARM TRPCL MOISTURE INTO SYSTEM. 

ELSEWHERE AT THE SURFACE...
RIDGE EXTENDS SE INTO AREA N OF 18N W OF 113W BRINGING STRONG NW 
WINDS ALONG BAJA CALIFORNIA COAST EXPECTED TO CONTINUE THROUGH 
FORECAST PERIOD.  FRESH NE TRADES DIMINISH AS HIGH PRES WEAKENS 
AND DRIFTS E.  

WWD MOVEMENT OF E PAC LOW PRES EXPECTED TO SQUEEZE PRES GRADIENT 
OVER ISTHMUS OF TEHUANTEPEC FORCING STRONG WINDS ACROSS GULF OF 
TEHUANTEPEC WITHIN 48 HRS. 

$$
WALLY BARNES