000
AXPZ20 KNHC 192134
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC WED NOV 19 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 
2130 UTC.

...ITCZ...
THE INTERTROPICAL CONVERGENCE ZONE IS ALONG THE LINE...07N77W 
07N110W 07N140W. SCATTERED MODERATE WITHIN 90 NM OF AXIS BETWEEN 
130W AND 140W.

...DISCUSSION...

UPPER LEVELS
LARGE UPPER TROUGH CONTINUES TO DOMINATE THE AREA. TROUGH AXIS 
EXTENDS FROM THE ARIZONA/NEW MEXICO BORDER THROUGH 25N120W TO A 
DEVELOPING CYCLONIC CIRCULATION NEAR 14N125W. A NEGATIVELY 
TILTED EXTENSION OF THE TROUGH EXTENDS SE TO 03N110W. THIS
TROUGH WILL SLOWLY WEAKEN TO A SHEAR AXIS THROUGH 24 HOURS BUT 
REMAIN IN PLACE. UPSTREAM POSITIVELY TILTED TROUGH WITH AN AXIS 
NW OF THE AREA IS AFFECTING THE AREA NW OF A LINE FROM 32N125W 
TO 20N140W. THE AREA NORTHWEST OF THE LINE IS MOIST ALOFT WITH 
BROKEN TO OVERCAST HIGH LEVEL CLOUDS. THE AREA BETWEEN THE FIRST 
TROUGH AXIS AND THE LEADING EDGE OF THE TROUGH WEST OF THE AREA 
IS DRY AND CLOUD FREE IN THE MIDDLE AND UPPER LEVELS INDICATING 
SUBSIDENCE IN THIS AREA. SOUTHEAST OF THE FIRST TROUGH AXIS 
SOUTH TO SOUTHWESTERLY FLOW IS ADVECTION MOISTURE AND SOME 
MIDDLE AND HIGH LEVELS CLOUDS EMANATING FROM ITCZ CONVECTION 
OVER MEXICO AND CENTRAL AMERICA.  

SURFACE
DISSIPATING STATIONARY FRONT IS OVER THE NORTHWEST PART OF THE 
AREA ALONG A LINE 32N135W TO 28N140W. OTHERWISE WEAK RIDGE IS N 
OF 12N W OF 105W. 

GAP WINDS...
STRONG PRES GRADIENT REMAINS ACROSS ISTHMUS OF TEHUANTEPEC.
AN 1800 UTC SHIP REPORT FROM SHIP WITH CALL SIGN C6SD9 IN THE 
GULF OF TEHUANTEPEC INDICATED 36 KT WINDS AND 16 FT SEAS. IN 
ADDITION A PARTIAL HIGH RESOLUTION QUIKSCAT PASS FROM 1142 UTC 
INDICATED NLY WINDS OF 40 KT WINDS. BASED ON THIS INFORMATION 
THE STORM WARNING FOR THE AREA HAS BEEN DOWNGRADED TO A GALE 
WARNING. WINDS ARE EXPECTED TO DROP BRIEFLY BELOW GALE FORCE IN 
ABOUT 24 HOURS BEFORE PICKING UP AGAIN IN YET ANOTHER SURGE OF 
NLY WINDS WHICH ARE EXPECTED TO REACH 40 KT OR SO BY LATE FRI. 

AN 1800 UTC SHIP REPORT FROM THE SHIP WITH CALL SIGN 3FMH7 NEAR 
THE GULF OF PAPAGAYO INDICATED NE WINDS OF 27 KT AND 9 FT SEAS. 
THESE WINDS ARE FORECAST TO CONTINUE THROUGH 48 HOURS.

$$
COBB