000
AXPZ20 KNHC 201605
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED DEC 20 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1545 UTC.

...ITCZ...

AXIS ALONG 6N77W 5N93W 9N112W 7N127W 8N140W. MODERATE CONVECTION 
WITHIN 90 NM N AND 180 NM S OF THE AXIS BETWEEN 77W AND 81W. 
ISOLATED CONVECTION ALSO IS FOUND WITHIN 120 NM OF THE AXIS 
BETWEEN 117W AND 140W. SCATTERED MODERATE CONVECTION IS 
OCCURRING IN ASSOCIATION WITH A SURFACE TROUGH FROM 11N TO 14N 
BETWEEN 111W AND 117W. 

...DISCUSSION...

AT THE SURFACE...A HIGH PRESSURE RIDGE PERSISTS ALONG 30N AND IS 
DRIVING NE WINDS UP TO 25 KT AND SEAS UP TO 14 FT BETWEEN 10 AND 
20N W OF 110W.  THE EARLIER MENTIONED NEAR-GALE FORCE WIND EVENT 
ALONG CABO CORRIENTES MEXICO APPEARS TO BE SHORT-LIVED AS WINDS 
HAVE SUBSIDED TO 20 TO 25 KT.  HOWEVER...N TO NW WINDS HAVE 
INCREASED THIS MORNING WITHIN THE GULF OF CALIFORNIA AND SEAS 
ARE LIKELY INCREASING TO NEAR 8 FT ACCORDINGLY.  ONLY WEAK GAP 
FLOW EVENTS ARE OCCURRING ALONG THE GULF OF TEHUANTEPEC AND GULF 
OF PAPAGAYO...PRODUCING LESS THAN 8 FT SEAS...AND THESE ARE 
EXPECTED TO CEASE WITHIN THE NEXT DAY OR SO AS THE MODERATE 
PRESSURE GRADIENT WEAKENS IN THE AREA.  THE NEXT EVENT OF 
SIGNIFICANCE WILL BE A COLD FRONT PUSHING INTO THE NW CORNER OF 
THE REGION WITH RAPIDLY BUILDING NW SWELL ON THU AND FRI.  IN 
THE TROPICS...THE SURFACE TROUGH NEAR 12N115W HAS PERSISTED WITH 
MODERATE CONVECTION...BUT FURTHER DEVELOPMENT INTO A TROPICAL 
CYCLONE APPEARS TO BE HIGHLY UNLIKELY BECAUSE OF HIGH SHEAR 
TYPICAL FOR THIS TIME OF YEAR.

ALOFT...A LARGE UPPER RIDGE IS CENTERED NEAR 11N118W AND A 
TROUGH EXTENDS SOUTHWARD OVER NW MEXICO FROM THE CLOSED LOW 
CENTERED OVER NEW MEXICO.  THE COMBINED STRONG WESTERLY FLOW 
BETWEEN THE TWO FEATURES IS ADVECTING A MOIST UPPER FLOW ACROSS 
MEXICO AND INTO THE GULF OF MEXICO. 

$$
LANDSEA