000
AXPZ20 KNHC 191516
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED DEC 19 2012

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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
MONSOON TROUGH 7N78W 5N93W 7W97W. ITCZ 7N97W TO 7N140W. 
SCATTERED MODERATE TO STRONG CONVECTION WITHIN 90 NM N AND 60 NM 
S OF AXIS BETWEEN 120W-128W.

...DISCUSSION...
BROAD UPPER LEVEL TROUGH OVER THE FAR W PORTION OF THE 
DISCUSSION AREA N OF 15N W OF 130W. A 95-125 JET STREAM IS E OF 
THE TROUGH FROM 20N129W TO THE NORTHERN BAJA PENINSULA INTO THE 
SW U.S. BROKEN TO OVERCAST MID AND UPPER LEVEL CLOUDS ARE WITHIN 
600 NM SE OF THE JET. A BROAD UPPER LEVEL RIDGE IS E OF THE 
TROUGH TO MEXICO WITH AN UPPER LEVEL ANTICYCLONIC CIRCULATION 
CENTERED OFF THE COAST OF MEXICO NEAR 10N97W. WITH THE 
EXCEPTION OF A FEW SHOWERS FROM 7N-9N BETWEEN 104W-106W MODERATE 
TO STRONG SUBSIDENCE WITH DRY AND STABLE AIR AT THE MIDDLE AND 
UPPER LEVELS IS E OF 110W.

COLD FRONT EXTENDS FROM 27N114W TO 23N125W. A FEW LIGHT SHOWERS 
ARE ALONG THE FRONT. NLY WINDS 20-25 KT ARE W OF THE FRONT WITH 
SEAS TO 13 FT. LARGE MIXED NE AND NW SWELLS ARE FROM 8N-20N W OF 
120W.

A STRONG COLD FRONT IS FORECAST TO MOVE INTO THE GULF OF MEXICO 
WITH STRONG HIGH PRES BUILDING BEHIND THE FRONT. THIS WILL 
TIGHTEN THE PRES GRADIENT ACROSS SOUTHERN MEXICO THU NIGHT 
BRINGING STORM FORCE WINDS THROUGH THE GULF OF TEHUANTEPEC. NLY 
WINDS ARE FORECAST TO BE 40-50 KT WITH SEAS BUILDING TO 19 FT BY 
EARLY FRI.

$$
DGS