000
AXPZ20 KNHC 240303
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC SAT DEC 24 2011

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 ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0300 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
THE MONSOON TROUGH AXIS EXTENDS FROM 08N84W TO 07N94W. THE ITCZ 
AXIS EXTENDS FROM 07N94W TO 10N123W TO BEYOND 06N140W. SCATTERED 
MODERATE ISOLATED STRONG CONVECTION WAS NOTED WITHIN 90 NM N OF 
ITCZ AXIS BETWEEN 100W AND 115W. SCATTERED MODERATE CONVECTION 
WAS NOTED WITHIN 90 NM OF ITCZ AXIS W OF 125W.

...DISCUSSION...

GULF OF CALIFORNIA...STRONG HIGH PRESSURE IN EXCESS OF 1040 MB 
PREVAILS OVER THE GREAT BASIN REGION PROMOTING STRONG NORTHERLY 
FLOW OVER THE ENTIRE LENGTH OF THE GULF OF CALIFORNIA WITH GALE 
FORCE WINDS NOTED. THE STRONG GRADIENT FLOW ACROSS THE GULF OF 
CALIFORNIA WILL SPILL OVER SOME OF THE GAPS ON THE BAJA 
PENINSULA...WITH CERTAIN AREAS OF WINDS TO 30 KT ALONG THE 
PACIFIC COAST OF BAJA THROUGH THE OVERNIGHT HOURS. THE RIDGING 
OVER THE GREAT BASIN HAS WEAKENED SLIGHTLY SINCE THE AFTERNOON 
AND WILL CONTINUE TO WEAKEN AS A SHORT WAVE TROUGH MIGRATES N OF 
THE RIDGE THROUGH THE NORTHERN ROCKIES. THE WEAKENING HIGH 
PRESSURE WILL RESULT IN DIMINISHING WINDS OVER THE GULF OF 
CALIFORNIA...BELOW GALE FORCE BY SAT MORNING...AND FURTHER 
DIMINISH TO 25 KT SUN. 

GULF OF TEHUANTEPEC...DENSE COLD AIR BEHIND THE COLD FRONT OVER 
THE GULF OF MEXICO IS PUSHING THROUGH THE CHIVELA PASS INTO THE 
GULF OF TEHUANTEPEC WITH NEAR GALE WINDS NOTED. WINDS ARE 
EXPECTED TO REACH GALE FORCE OVERNIGHT AS HIGH PRES BUILDS INTO 
THE SOUTHERN PLAINS...WHICH WILL INCREASE THE WINDS FUNNELING 
INTO THE GULF OF TEHUANTEPEC. WINDS WILL DIMINISH BELOW GALE 
FORCE BY SAT AFTERNOON AS THE DENSER AIR OVER THE GULF OF MEXICO 
MODIFIES REDUCING THE WINDS FUNNELING THROUGH THE CHIVELA PASS. 
ANOTHER SURGE OF COLD AIR WILL REACH THE BAY OF CAMPECHE 
SUN...INCREASING WINDS OVER THE GULF OF TEHUANTEPEC WITH WINDS 
ONCE AGAIN EXPECTED TO REACH GALE FORCE SUN NIGHT. 

GULF OF PAPAGAYO...FRESH TRADEWINDS OVER THE WESTERN CARIBBEAN 
WILL FUNNEL INTO THE GULF OF PAPAGAYO. WINDS WILL PEAK DURING 
THE EARLY MORNING HOURS WITH THE ADDITION OF NOCTURNALLY DRIVEN 
KATABATIC WINDS.

HIGH PRES 1036 MB IS CENTERED N OF THE AREA NEAR 37N127W WITH 
RIDGE EXTENDING SE TO NEAR 17N106W. THE PRESSURE GRADIENT 
BETWEEN THIS AREA OF HIGH PRESSURE AND LOWER PRESSURE IN THE 
VICINITY OF THE ITCZ IS MAINTAINING A LARGE AREA OF FRESH TO 
STRONG TRADEWINDS OVER MUCH OF THE AREA N OF 10N W OF 110W. THE 
AREA OF HIGH PRESSURE WILL REMAIN N OF THE AREA THROUGH SUN 
NIGHT...MAINTAINING THIS AREA OF TRADEWINDS... WITH SEAS 
BUILDING TO 13 FT. 

$$
AL