000
AXPZ20 KNHC 121513
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC MON JAN 12 2009

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...ITCZ...
ITCZ IS ALONG 4N77W 7N85W 5N90W 8N120W 5N140W. NUMEROUS 
MODERATE TO STRONG FROM 06N TO 11N BETWEEN 98W AND 112W.

...DISCUSSION...
UPPER LEVEL TROUGH OVER THE FAR NW PORTION OF THE DISCUSSION 
AREA FROM 32N140W TO 29N133W. S OF THE TROUGH AN UPPER LEVEL 
RIDGE IS S OF 28N ALONG 138W. MODERATE TO STRONG SUBSIDENCE WITH 
DRY STABLE AIR COVERS THE AREA W OF 130W. AN UPPER LEVEL TROUGH
E OF THE RIDGE WITH AXIS 22N128W TO 7N117W. UPPER LEVEL 
DIFFLUENT FLOW SE OF THE TROUGH AXIS IS SUPPORTING NUMEROUS 
MODERATE TO STRONG CONVECTION ALONG THE ITCZ. MIDDLE TO UPPER 
LEVEL RIDGE IS N OF 25N BETWEEN 115W AND 130W WITH A DEEP LAYER 
TROUGH E OF THE RIDGE. THE TROUGH EXTENDS FROM SW TEXAS ACROSS 
NORTHERN MEXICO THROUGH SOUTHERN BAJA CALIFORNIA TO 25N120W. A 
90-120 KT JET STREAM IS SE OF THE TROUGH OVER NORTHERN MEXICO.
A BROAD MID/UPPER LEVEL TROUGH COVERS THE AREA SE OF THE TROUGH.

STATIONARY FRONT OVER WESTERN MEXICO IS DISSIPATING...HOWEVER
A 1027 MB SURFACE HIGH IS OVER NE MEXICO MAINTAINING A STRONG
PRES GRADIENT ACROSS SOUTHERN MEXICO WITH GALE FORCE WINDS 
CONTINUING THROUGH THE GULF OF TEHAUNTEPEC. OTHERWISE BROAD 
RIDGE DOMINATES THE AREA N OF 11N W OF 120W.

$$
DGS