000
AXPZ20 KNHC 230308
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC FRI DEC 23 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 09N85W TO 07N94W. THE ITCZ 
AXIS EXTENDS FROM 07N94W TO 10N118W WHERE THERE IS A BREAK IN 
THE ITCZ DUE TO A SURFACE TROUGH FROM 14N117W TO 09N120W. THE 
ITCZ THEN CONTINUES FROM 08N121W AND EXTENDS TO BEYOND 07N140W. 
SCATTERED MODERATE CONVECTION WAS NOTED WITHIN 90 NM N OF AXIS W 
OF 128W. 

...DISCUSSION...

HIGH PRES 1030 MB IS CENTERED N OF THE AREA NEAR 38N133W WITH 
SURFACE RIDGE EXTENDING SE TO NEAR 17N106W. THE PRESSURE 
GRADIENT BETWEEN THE RIDGE OF HIGH PRESSURE AND LOWER PRESSURE 
IN THE VICINITY OF THE ITCZ IS SUPPORTING FRESH TRADEWINDS 
REACHING AS FAR E AS 112W. THIS AREA OF HIGH PRESSURE WILL BUILD 
TO 1034 MB BY FRI. THIS WILL FURTHER TIGHTEN THE PRESSURE 
GRADIENT AND STRENGTHEN THE TRADEWINDS WHILE EXPANDING THE AREAL 
COVERAGE OF THE FRESH TO STRONG TRADEWINDS. 

GAP WINDS...
GULF OF CALIFORNIA...NEAR GALE FORCE WINDS ARE CURRENTLY OVER 
THE GULF N OF 28N. WINDS WILL FURTHER INCREASE TO GALE FORCE AND 
SPREAD SOUTHWARD OVERNIGHT IN RESPONSE TO HIGH PRES IN EXCESS OF 
1040 MB BUILDING OVER THE GREAT BASIN REGION. THE GALE SHOULD BE 
RELATIVELY SHORT LIVED AS HIGH PRES IS EXPECTED TO SHIFT 
EASTWARD INTO THE PLAINS OVER THE WEEKEND...WEAKENING THE PRES 
GRADIENT OVER THE GULF OF CALIFORNIA. HOWEVER...NEAR GALE WINDS 
ARE EXPECTED TO CONTINUE THROUGH SAT AFTERNOON.

GULF OF TEHUANTEPEC...COLD FRONT CURRENTLY OVER THE GULF OF 
MEXICO IS EXPECTED TO REACH THE BAY OF CAMPECHE FRI. WINDS 
FUNNELING THOUGH THE CHIVELA PASS WILL STRENGTHEN WINDS OVER THE 
GULF OF TEHUANTEPEC BY FRI MORNING. WINDS ARE FORECAST TO REACH 
GALE FORCE OVERNIGHT FRI INTO SAT AS HIGH PRES BEGINS TO EMERGE 
IN THE SOUTHERN PLAINS...WHICH WILL INCREASE THE WINDS FUNNELING 
INTO THE GULF OF TEHUANTEPEC.

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.

$$
AL