000
AXPZ20 KNHC 222133
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC WED DEC 22 2010

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 
2100 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ALONG 03N77W TO LOW 
PRES 07N98W TO 05N110W TO 10N125W TO 08N140W. NO SIGNIFICANT 
CONVECTION. 

...DISCUSSION...
A COLD FRONT ENTERS THE FORECAST AREA NEAR 30N118W THEN 
CONTINUES SW TO TO 26N122W TO 24N130W. AN ASCAT PASS FROM 1748 
UTC SHOWED W TO NW WINDS IN THE 20 TO 25 KT RANGE BEHIND THE 
FRONT TO NEAR 130W. A FRONTAL TROUGH LIES JUST AHEAD OF THE COLD 
FRONT AND STRETCHES FROM 30N116W TO 21N125W. SW WINDS OF 20 KT 
ARE NOTED BETWEEN THE TROUGH AND THE FRONT PER AN ASCAT PASS AND 
SHIP OBSERVATIONS. A LONG WAVE TROUGH WITH ITS MEAN AXIS ALONG 
THE WESTERN PORTION OF U.S. SUPPORTS THESE FEATURES. THE COLD 
FRONT IS EXPECTED TO OVERTAKE THE FRONTAL TROUGH THIS EVENING 
WITH THE MERGED FRONT MOVING ACROSS THE NORTHERN BAJA CALIFORNIA 
PENINSULA TONIGHT. SURFACE WINDS HAVE INCREASED UP TO 25 KT 
AHEAD OF THE FRONTAL TROUGH OVER THE NORTHERN PORTION OF THE 
GULF OF CALIFORNIA. AN EARLIER ASCAT PASS VERIFIED THESE WINDS 
SPEEDS. ANOTHER COLD FRONT IS FORECAST TO REACH THE FAR NW 
CORNER OF THE FORECAST AREA EARLY FRI MORNING. EXPECT INCREASING 
WINDS OF 20 TO 25 KT AHEAD OF THE FRONT COVERING ROUGHLY THE 
AREA N OF 26N W OF 127W. WINDS WILL VEER TO THE NW WITH THE 
FRONTAL PASSAGE. LONG PERIOD NW SWELL WILL FOLLOW THE FRONT.
 
CROSS EQUATORIAL SE WINDS AT 20 KT ARE NOTED OVER THE TROPICAL 
WATERS S OF 05N W OF 120W. THIS WEATHER PATTERN IS FORECAST TO 
PERSIST THROUGH THE NEXT 48 HOURS. 
   
GAP WINDS...
SOME LATE NIGHT DRAINAGE FLOW IS EXPECTED TO MAINTAIN 20 KT N 
WINDS IN THE GULF OF TEHUANTEPEC AROUND SUNRISE THROUGH FRI. 
ACCORDING TO THE COMPUTER MODELS...A GALE FORCE WIND EVENT WILL 
TAKE PLACE ACROSS THE GULF OF TEHUANTEPEC SAT NIGHT INTO SUN. 

GAP WIND OF 20 KT WILL CONTINUE TO PULSE THROUGH THE GULF OF 
PAPAGAYO OVER THE NEXT COUPLE OF DAYS. THE WINDS ARE GREATEST 
DURING THE OVERNIGHT AND MORNING HOURS WITH THE AID OF DRAINAGE 
FLOW. 

NLY WINDS AT 20 KT WILL CONTINUE TO DRAIN INTO THE GULF OF 
PANAMA THROUGH THU MORNING. 
     
$$
GR