000
AXPZ20 KNHC 111513
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SUN JAN 11 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 7N77W 5N80W 7N90W 6N140W. NO SIGNIFICANT 
CONVECTION.

...DISCUSSION...
AN UPPER LEVEL TROUGH OVER THE W PORTION OF THE DISCUSSION AREA
EXTENDS FROM A CYCLONIC CIRCULATION NEAR 30N140W TO 5N135W. A 
BROAD UPPER LEVEL RIDGE IS SE OF THE TROUGH FROM 29N128W TO 
10N116W. DIFFLUENT UPPER LEVEL FLOW BETWEEN THE TROUGH AND THE 
RIDGE IS ENHANCING SHOWER ACTIVITY FROM 9N-15N BETWEEN 126W-132W.
MID/UPPER LEVEL TROUGH WITH AXIS FROM SW TEXAS ACROSS CENTRAL 
BAJA CALIFORNIA TO  28N125W. MODERATE TO STRONG SUBSIDENCE WITH 
DRY STABLE AIR AT THE MIDDLE AND UPPER LEVELS OF THE ATMOSPHERE 
COVERS THE AREA N OF 25N W OF 110W. UPPER LEVEL TROUGH IN THE 
TROPICS EXTENDS FROM 21N114W TO 6N101W. SCATTERED MODERATE TO 
STRONG CONVECTION JUST E OF THE TROUGH FROM 8N-10N BETWEEN 
103W-108W.

BROAD SURFACE RIDGE COVERS THE AREA N OF 15N W OF 120W. BROKEN 
TO OVERCAST STRATOCUMULUS CLOUDS BLANKET THE AREA N OF 15N W OF 
125W. SURFACE TROUGH IS ANALYZED ALONG THE ITCZ FROM 8N94W TO 
4N95W. SCATTERED SHOWERS ARE WITHIN 180 NM E OF TROUGH FROM 
5N-8N. STRONG PRES GRADIENT OVER NORTHERN MEXICO IS PRODUCING 
GALE FORCE WINDS ACROSS THE GULF OF CALIFORNIA. THE GRADIENT 
WILL WEAKEN EARLY MON WITH WINDS BELOW GALE FORCE.

$$
DGS