000
AXPZ20 KNHC 081620
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC MON DEC 08 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 
1515 UTC.

...ITCZ...
ITCZ AXIS ALONG 04N78W TO 07N114W TO 10123W TO 08N130W TO 
08N140W.  SCATTERED MODERATE CONVECTION WITHIN 120 NM N OF AXIS 
99W-106W.

...DISCUSSION...
MID/UPPER LEVEL TROUGH RUNS SW FROM 32N127W TO WELL DEFINED 
CYCLONIC VORTEX AT 21N139W DRIFTING W.  SURFACE TROUGH UNDER 
VORTEX ASSOCIATED WITH SCATTERED CONVECTION ENHANCED BY 
DIFFLUENT FLOW ALOFT MOVING W OF AREA WITHIN NEXT 24-36 HRS.

DOWNSTREAM MID/UPPER LEVEL RIDGE CENTERED AT 110-113W ADVECTING 
LARGE SUPPLY OF TROPICAL MOISTURE AND ITCZ DEBRIS INTO BAJA 
CALIFORNIA AND CENTRAL MEXICO.  UPPER LEVEL DIFFLUENT FLOW 
BETWEEN RIDGE AND VORTEX ENHANCING SCATTERED MODERATE ISOLATED 
STRONG FROM 12N TO 17N BETWEEN 119W AND 126W.  FURTHER E...LARGE 
AMPLITUDE TROUGH DIGS S FROM YUCATAN PENINSULA TO 00N96W WITH 
VERY DRY AIR MASS E OF 100W DUE TO MODERATE TO STRONG SUBSIDENCE 
ALOFT. 

ELSEWHERE AT THE SURFACE...
TROUGH FROM 08N-15N ALONG 127W TIGHTENS PRES GRADIENT TO SUPPORT 
STRONG WINDS ALONG AXIS.  WEAK SECOND TROUGH FROM 10N-15N ALONG 
137W SHOULD MOVE W OF AREA WITHIN 24 HRS HAS NO SIGNIFICANT 
CONVECTION OR WINDS ASSOCIATED WITH IT. 

GULF OF TEHUANTEPEC WINDS LIKELY BE UNDER 20 KT WITHIN NEXT 6 
HRS WHILE GULF OF PAPAGAYO NE WINDS SHOULD DIMINISH BUT LAST FOR 
NEXT 36 HRS.

$$
WALLY BARNES