000
AXPZ20 KNHC 180939
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SUN JAN 18 2009

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN
FROM THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 4N77W 1N90W 7N122W 6N140W. SCATTERED 
MODERATE TO ISOLATED STRONG CONVECTION FROM 04N TO 06N BETWEEN 
103W AND 106W. SCATTERED MODERATE CONVECTION FROM 07N TO 13N 
BETWEEN 120W TO 125W. 

...DISCUSSION...
LARGE DEEP LAYERED LOW COVERS THE AREA FROM 7N TO 25N WITH THE 
UPPER LOW CENTERED NEAR 19N24W AND A 1014 MB SURFACE LOW NEAR 
17N127W AND SURFACE TROUGH EXTENDING FROM 21N127W TO 14N128W. 
UPPER TROUGH IS WEAKENING AS IT IS BLOCKED BY AN UPPER RIDGE TO 
THE E EXTENDING FROM 7N102W TO 30N113W AND A SECOND UPPER RIDGE 
TO THE W COVERING THE AREA W OF 132W. A BROAD AREA OF DIFFLUENCE 
ALOFT E THE UPPER TROUGH...GENERATING SCATTERED MODERATE 
CONVECTION E OF THE SURFACE TROUGH FROM 15N TO 19N BETWEEN 122W 
TO 126W AND COVERING THE AREA WITH SCATTERED MODERATE TO 
ISOLATED STRONG CONVECTION WITHIN 150/175 NM OF LINE FROM 
10N103W TO 25N116W. 

GULF OF TEHUANTEPEC AND IMMEDIATE AREA SW OF IT CONTINUE UNDER 
WEAKENING GALE FORCE WINDS...EXPECTED TO BE BELOW GALE FORCE IN 
12 HOURS AS HIGH PRES BUILDS OVER THE GULF OF MEXICO. 

GULF OF PAPAGAYO STRONG NE WINDS CONTINUE FROM W CARIBBEAN BEGIN 
TO WEAKEN BUT REMAIN NEAR 20 KT FOR THE NEXT 48 HOURS. 

STRONG COLD FRONT JUST NW OF THE REGION AND WILL ENTER LATER 
THIS MORNING BRINGING STRONGER WINDS IN ITS WAKE BECOMING  
DIFFUSE MON AFTERNOON AS ITS SUPPORTING UPPER TROUGH STALLS JUST 
W OF BLOCKING RIDGE. LARGE AREA OF 10 TO 19 FT LONG PERIOD 
SWELLS CONTINUE TO COVER THE AREA N OF 7N W OF 123W. 

$$
WALLACE