000
AXPZ20 KNHC 090904
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC SAT DEC 09 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0345 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG...7N78W 6N85W 5N130W 7N140W. 
SCATTERED MODERATE TO STRONG CONVECTION WITHIN 90 NM EITHER SIDE 
OF AXIS FROM 125W TO 130W AND WITHIN 75  NM N OF AXIS 130W TO 
133W.

...DISCUSSION...

MID TO UPPER LEVEL RIDGE EXTEND FROM ANTICYCLONIC CIRCULATION 
NEAR 12N123W TO 32N125W. THE N PORTION OF THE RIDGE IS MOVING 
EWD AS A SHORTWAVE TROUGH APPROACHES THE AREA FROM THE W. A 
90-105 KT JET STREAM AHEAD OF THE TROUGH ENTERS THE DISCUSSION 
AREA NEAR 29N140W TO 32N120W. MODERATE TO STRONG SUBSIDENCE IS 
NOTED N OF 20N W OF 115W. UPPER LEVEL DIFFLUENT FLOW W OF THE 
ANTICYCLONE IS ENHANCING ITCZ CONVECTION W OF 124W. A WEAKENING 
SHORTWAVE TROUGH IS MOVING NE OVER NORTHERN BAJA CALIFORNIA AND 
SHOULD BE NE OF THE AREA SOON.

MID TO UPPER LEVEL RIDGE EXTENDS FROM SOUTHERN NEW MEXICO SW 
INTO NW MEXICO THEN TO AROUND 25N109W. MODERATE TO STRONG 
SUBSIDENCE N OF 12N BETWEEN 105W AND 115W. DOWNSTREAM TROUGH 
EXTENDS FROM THE BIG BEND OF TEXAS THROUGH CENTRAL MEXICO TO 
NEAR 14N105W. BROKEN TO OVERCAST CLOUDS CONTINUE ACROSS MUCH OF 
MEXICO.

MID/UPPER LEVEL ANTICYCLONE OVER NICARAGUA AND ASSOCIATED 
RIDGING DOMINATED THE PACIFIC E OF 100W AND WAS CHARACTERIZED BY 
AN AREA OF STRONG SUBSIDENCE. THIS AREA OF SUBSIDENCE WAS 
LIMITING CONVECTION ALONG THE ITCZ E OF 100W. 

DISSIPATING COLD FRONT EXTENDS FROM 32N120W TO 23N129W. AS THE 
FRONT WEAKENS WINDS WITH THE FRONT HAVE DECREASED...HOWEVER 
LARGE SWELLS CONTINUE ACROSS THE AREA. PRES GRADIENT REMAINS 
TIGHT OVER MEXICO AND GALE FORCE WINDS CONTINUE IN THE GULF OF 
TEHUANTEPEC.


$$
DGS