000
AXPZ20 KNHC 270957
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC TUE NOV 27 2007

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 
0900 UTC.
 
...ITCZ...
INTERTROPICAL CONVERGENCE ZONE...AXIS ALONG 9N85W 7N93W 10N120W 
7N140W.  SCATTERED MODERATE WITHIN 180 NM OF AXIS FROM 118W TO 
126W AND W OF 132W.  SCATTERED MODERATE WITHIN 60 NM OF AXIS E 
OF 101W. 

...DISCUSSION...
LARGE UPPER LEVEL CYCLONIC VORTEX AT 27N123W DOMINATES WIND FLOW 
ALOFT N OF 17N W OF 110W.  ATTENDANT TROUGH AXIS TO 20N124W TURN 
W TO 21N140W.  MODERATE TO STRONG SUBSIDENCE WITHIN 150 NM OF 
AXIS MAINTAINS DRY AIR MASS ALOFT IN AREA AS 115 KT JET CORE 
DIGS S AROUND ITS BASE.  ELSEWHERE W OF 100W MID-UPPER LEVEL 
RIDGE CREST IS FLATTENED BY MENTIONED VORTEX MAKING MAKING ZONAL 
FLOW FROM 6N-18N W OF 120W.   

SECOND UPPER RIDGE EXTENDS NW FROM EQUATOR ALONG CENTRAL AMERICA 
INTO CENTRAL MEXICO.  WEAK UPPER TROUGH ORIENTED NW-SE IS 
TRAPPED BETWEEN THE TWO RIDGES AND HELPS DIFFLUENT FLOW NEAR 
15N120W ENHANCING SCATTERED CONVECTION IN PLACE.   THIS MOISTURE 
PLUME PLUS SOME FROM ITCZ BEING ADVECTED BY 90 KT WIND INTO BAJA 
CALIFORNIA.

AT THE SURFACE...HIGH PRES CENTER 1028 MB AT 35N128W HAS RIDGE 
EXTEND TO 13N110W.  REBUILDING RIDGE STRENGTHENS AND EXPAND NE  
TRADES N OF 10N W OF 120W.

ELSEWHERE...HIGH PRES 1026 MB OVER TEXAS DRIVING STRONG FLOW 
ACROSS BAY OF CAMPECHE FUNNELING INTO GULF OF TEHUANTEPEC WITH 
GALE FORCE WINDS BEGINNING WITHIN 6 HR OR LESS.  EVENT LASTING 
LITTLE MORE THAN 48 HRS AS HIGH PRES MOVES QUICKLY E.  

SIMILARLY GULF OF PAPAGAYO WINDS INCREASE AS HIGH PRES REBUILDS 
ACROSS CARIBBEAN FORCING STRONG WINDS AGAINST MOUNTAIN GAPS IN 
CENTRAL AMERICA.  WHILE NOT AS STRONG AS TEHUANTEPEC...PAPAGAYO 
EXPECTED TO REACH 20-25 KT AT ITS PEAK WITHIN 48 HR.
  
$$
WALLY BARNES