000
AXPZ20 KNHC 212204
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC FRI NOV 21 2008

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

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2145 UTC.

...ITCZ...
THE INTERTROPICAL CONVERGENCE ZONE IS CENTERED ALONG 08N83W 
06N95W 09N113W 07N125W 07N140W. SCATTERED MODERATE WITHIN 90-120 
NM N OF AXIS BETWEEN 100W AND 116W. SIMILAR CONVECTION IS NEAR 
08N128W. 

...DISCUSSION...

AN UPPER LEVEL TROUGH EXTENDS FROM 30N127W TO 20N129W. A SECOND 
UPPER TROUGH IS NOTED FROM 22N120W TO 08N116W. MID/UPPER LEVEL 
MOISTURE IS AHEAD OF BOTH TROUGHS THAT ARE EXPECTED TO MERGE 
ALONG 120W N OF THE EQUATOR BY LATE SAT. AN UPPER-LEVEL RIDGE 
ANCHORED ON A HIGH OVER THE SW CARIBBEAN DOMINATES THE EPAC EAST 
OF 105W. UPPER DIFFLUENCE BETWEEN THIS RIDGE AND THE EASTERNMOST 
TROUGH IS ENHANCING CONVECTION ALONG THE ITCZ BETWEEN 100W AND 
116W. ANOTHER UPPER-LEVEL RIDGE CENTERED WEST OF THE FORECAST 
REGION IS PRODUCING SUBSIDENCE/DRY AIR ACROSS MUCH OF THE AREA S 
OF 20N W OF 120W EXCEPT ALONG THE ITCZ AXIS.   
 
AT THE SURFACE...A 1030 MB HIGH LOCATED N OF AREA NEAR 33N135W 
EXTENDS A RIDGE OVER THE DISCUSSION AREA COVERING THE AREA N OF 
12N AND W OF 110W. THIS FEATURE IS PRODUCING A BELT OF TRADE 
WINDS IN THE 20 T0 25 KT RANGE MAINLY BETWEEN 7N AND 22N. A 1412 
UTC HIGH RESOLUTION QUIKSCAT PASS CONFIRMED THESE WIND SPEEDS.   

GAP WINDS...NORTHERLY WINDS IN AND DOWNSTREAM OF THE GULF OF  
TEHUANTEPEC HAVE ONCE AGAIN REACHED GALE FORCE PER A 1230 UTC 
HIGH RESOLUTION QUIKSCAT PASS FROM THIS MORNING. THESE WINDS ARE 
EXPECTED TO PERSIST DURING THE UPCOMING WEEKEND AS ANOTHER COLD 
SURGE MOVES INTO THE AREA WITH WINDS INCREASING TO A STRONG GALE 
WITHIN 12 HOURS THEN DIMINISHING BELOW GALE BY LATE SUN. 

NE WINDS OF 20 TO 25 KT ARE IN THE GULF OF PAPAGAYO. THESE WINDS 
MAY BRIEFLY WEAKEN AND THEN INCREASE TO 20 TO 30 KT LATE SAT AND 
SUN. 

$$
COBB