000
AXPZ20 KNHC 220915
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC FRI DEC 22 2006

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0915 UTC.

...ITCZ...
THE ITCZ AXIS IS ALONG 6N77W 4N100W 5N130W 4N140W 
6N140W. VERY LITTLE DEEP CONVECTION NOTED AGAIN TONIGHT EXCEPT 
FOR THE SCATTERED MODERATE/ISOLATED STRONG ACTIVITY WITHIN 90 NM 
S OF THE AXIS BETWEEN 128W AND 136W.

...DISCUSSION...
UPPER LEVELS...AN UPPER RIDGE IS OVER THE FAR NW PORTION OF THE 
AREA WHILE AN UPPER TROUGH AXIS EXTENDS SOUTHWEST FROM THE 
CUTOFF LOW OVER THE CENTRAL UNITED STATES TO 19N119W. UPPER HIGH 
JUST S OF GUATEMALA IS AFFECTING MUCH OF THE AREA BETWEEN 85W 
AND 110W.  THE JET BETWEEN THESE TWO FEATURES IS ADVECTING 
SIGNIFICANT MOISTURE ACROSS MEXICO AND INTO THE GULF OF MEXICO.  
ON THE WESTWARD SIDE OF THE UPPER TROUGH AND IN THE VICINITY OF 
THE UPPER HIGH...EXTENSIVE DRY AND STABLE AIR DOMINATES. 

SURFACE FEATURES...A 1028 MB SURFACE HIGH IS NEAR 30N130W AND 
EXPECTED TO DRIFT NE OVER THE NEXT COUPLE DAYS.  FRESH 
TRADEWINDS ASSOCIATED WITH THIS FEATURE PERSIST FROM 10N-20N 
MAINLY WEST OF 120W. ONLY SLIGHT WEAKENING ANTICIPATED IN THESE 
WINDS THROUGH SUN. THE ASSOCIATED SHORT PERIOD WIND WAVES WILL 
MIX WITH THE LARGE...LONG PERIOD NW SWELL SPREADING THROUGH THE 
AREA THROUGH THE WEEKEND. NW WINDS ARE RELAXING IN THE GULF OF 
CALIFORNIA BUT THIS WILL ONLY BE TEMPORARY. BOTH NAM/GFS 
SUGGESTING 20 TO 30 KT NW WINDS WILL INCREASE BY EARLY SAT IN 
RESPONSE TO STRONG HIGH PRESSURE BUILDING N OF THE AREA AND 
INTERACTING WITH THE INVERTED TROUGH OVER THE AREA. ASSOCIATED 
STEEP NNW WIND WAVES WILL AGAIN BE LARGEST S OF 26N AT THE TAIL 
END OF THE FETCH. 
 
GAP WINDS...
NO SIGNIFICANT GAP FLOW WINDS ARE OCCURRING NOW OR OVER THE NEXT 
TWO DAYS AT TEHUANTEPEC OR PAPAGAYO.  HOWEVER...BY EARLY 
CHRISTMAS MORNING...A STRONG COLD FRONT PUSHING ACROSS THE GULF 
OF MEXICO MAY INITIATE A TEHUANTEPEC WIND EVENT.

$$
WILLIS