000
AXPZ20 KNHC 210920
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC MON DEC 21 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...
AXIS IS ALONG 05N77W TO 05N105W TO 10N120W TO 09N140W.
NO SIGNIFICANT CONVECTION.

...DISCUSSION...
AN UPPER LEVEL TROUGH IS APPROACHING THE FAR NW PORTION OF THE 
DISCUSSION AREA. OTHERWISE A LARGE RIDGE DOMINATES MUCH OF THE
AREA W OF AROUND 105W,..WITH AXIS FROM SOUTHERN CALIFORNIA 
ACROSS BAJA CALIFORNIA TO 5N121W. A 110-130 KT JETSTREAM ENTERS 
THE AREA AT 27N140W THEN NE TO 32N136W. THE SW JET IS ADVECTING 
TROPICAL MOISTURE NWD ACROSS THE RIDGE. THE JET CURVES AROUND 
THE RIDGE WITH NW WINDS 95-100 KT FROM 32N115W ACROSS WESTERN 
MEXICO TO 16N102W. A SHARP UPPER LEVEL TROUGH EXTENDS FROM NE 
MEXICO ACROSS CENTRAL MEXICO TO 5N104W. A 95-100 KT JETSTREAM IS 
E OF THE TROUGH FROM 14N94 ACROSS SOUTHERN MEXICO INTO THE GULF 
OF MEXICO. THIS JET IS ALSO ADVECTING TROPICAL MOISTURE NWD INTO 
SOUTHERN MEXICO.

DISSIPATING COLD FRONT IS IN THE FAR NW PART OF THE AREA EXTENDS 
FROM 32N127W TO 25N140W. THE COLD FRONT WILL BECOME DIFFUSE 
LATER TODAY BUT LONG PERIOD NW SWELL THAT GENERATED BEHIND THIS 
FRONT WILL SPREAD S AND E ACROSS THE AREA MAINLY N OF 08N AND W 
OF 120W. A SURFACE TROUGH IS ANALYZED ALONG THE ITCZ FROM 
14N122W TO 1012 MB LOW NEAR 11N122W TO 7N123W. A FEW SHOWERS ARE 
NEAR THE LOW CENTER.

N TO NE WINDS OF 20 TO 25 KT ARE OCCURRING THROUGH THE GULF OF 
TEHUANTEPEC AND ARE EXPECTED TO CHANGE LITTLE THROUGH LATE MON 
NIGHT THEN DECREASE ON TUE.

THE COMBINATION OF STRONG TRADE WINDS IN THE CARIBBEAN AND LOCAL 
DRAINAGE EFFECTS WILL ALLOW FOR NE TO E 20 KT WINDS THROUGH THE 
GULF OF PAPAGAYO...THESE CONDITIONS ARE EXPECTED TO CONTINUE 
THROUGH THE NEXT 24 HOURS THEN DECREASE TUE.

FOR ADDITIONAL INFORMATION PLEASE VISIT 
HTTP://WWW.HURRICANES.GOV/MARINE
  
$$
DGS