000
AXPZ20 KNHC 020908
TWDEP 

TROPICAL WEATHER DISCUSSION                                    
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
1005 UTC WED JAN 02 2013

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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

...SPECIAL FEATURE...                                         
GULF OF TEHUANTEPEC STORM WARNING...A STRONG COLD FRONT WILL 
SWEEP ACROSS THE GULF OF MEXICO THU AND REACH THE ISTHMUS OF 
TEHUANTEPEC THU EVENING. HIGH PRES BUILDING BEHIND THE FRONT 
WILL PRODUCE A TIGHT PRES GRADIENT ACROSS SOUTHERN MEXICO THU 
NIGHT AND FUNNEL COLD AIR THROUGH THE CHIVELA PASS INTO THE GULF 
OF TEHUANTEPEC. STORM FORCE WINDS ARE EXPECTED IN THE REGION 
STARTING THU NIGHT AND CONTINUE THROUGH FRI MORNING. WINDS TO 
GALE FORCE ARE EXPECTED FRI THROUGH SAT MORNING. MAX SEAS 
GENERATED BY THIS HIGH WIND EVENT ARE PROJECTED TO BE 20 TO 22 
FT FRIDAY. LARGE SWELL WILL SPREAD DOWNWIND FROM TEHUANTEPEC 
REGION FRI THROUGH SUN...WITH 8 FT SEAS REACHING NEAR 110W.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...              
MONSOON TROUGH EXTENDS FROM 08N78W TO 07N88W TO 05N105W...THEN 
ITCZ AXIS TO 09N135W TO 08N140W. SCATTERED MODERATE TO STRONG 
CONVECTION IS WITHIN 60 NM OF AXIS BETWEEN 125W AND 135W.  

...DISCUSSION...AN UPPER RIDGE ALONG 130W IS BECOMING LESS 
AMPLIFIED AND SHIFTING EAST AHEAD OF A VIGOROUS SHORT WAVE 
TROUGH MOVING EASTWARD THROUGH 145W. AN ASSOCIATED 1025 MB 
SURFACE HIGH CENTERED NEAR 25N130W IS SUPPORTING FRESH TRADE 
WIND FLOW FROM 10N TO 20N W OF 120W. THESE WINDS WILL DIMINISH 
OVER THE NEXT 48 HOURS AS THE HIGH PRES WEAKENS AND SHIFTS NE 
AHEAD OF THE ADVANCING TROUGH. 

A RECENT ALTIMETER PASS VERIFIED WAVEWATCH III AND ECWAVE 
INITIALIZATIONS DEPICTING A LARGE AREA OF NW SWELL STILL PLACE 
FROM 08N TO 20N W OF 120W IN MAINLY LONGER PERIOD NW SWELL 
MIXING WITH SHORTER PERIOD NE SWELL DUE TO TRADE WIND FLOW. WAVE 
MODELS CONTINUE TO SHOW THE LONG PERIOD SWELL DECAYING 
SIGNIFICANTLY OVER THE NEXT COUPLE OF DAYS. 

CONVERGING TRADE WINDS IN THE LOWER LEVELS COMBINED WITH 
DIVERGENCE ALOFT AHEAD OF THE TROUGH IS ENHANCING SCATTERED 
CONVECTION WITHIN 60 NM OF THE ITCZ BETWEEN 125W AND 135W. THESE 
SHOWER WILL SHIFT EAST AHEAD OF THE TROUGH OVER THE NEXT COUPLE 
OF DAYS...BUT THE  COVERAGE AND INTENSITY OF THIS CONVECTION 
WILL DECREASE AS THE TRADE WIND FLOW DIMINISHES AND THE UPPER 
TROUGH BECOMES LESS AMPLIFIED. 

GULF OF PAPAGAYO...AN ASCAT PASS FROM 03 UTC INDICATED FRESH GAP 
WIND FLOW THROUGH THE GULF OF PAPAGAYO. THIS IS DUE TO STRONG 
TRADE WIND FLOW IN THE SW CARIBBEAN MOVING THROUGH SOUTHERN 
NICARAGUA INTO THE GULF. THIS WILL BE ENHANCED BY EARLY MORNING 
DRAINAGE FLOW INCREASING WINDS TO 25 KT. WINDS WILL DIMINISH BY 
LATE MORNING...BUT A REPEAT OF THE STRONG GAP WINDS IS EXPECTED 
OVERNIGHT TONIGHT INTO FRI MORNING. 
 
$$ 
CHRISTENSEN