000
AXPZ20 KNHC 031531
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC TUE JAN 03 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 ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...MONSOON 
TROUGH EXTENDS FROM 07N78W TO 08N85W TO 05N93W...THEN ITCZ AXIS 
FROM 05N93W TO BEYOND 06N140W. SCATTERED MODERATE CONVECTION 
WITHIN 90 NM S OF MONSOON TROUGH BETWEEN 80W AND 95W. SCATTERED 
MODERATE CONVECTION WITHIN 30 NM N OF ITCZ AXIS BETWEEN 105W AND 
110W. SCATTERED MODERATE WITHIN 60 NM N OF ITCZ AXIS BETWEEN 
125W AND 130W.

...DISCUSSION...
W OF 110W...A 1028 MB HIGH PRES IS CENTERED NEAR 32N132W. 
OVERNIGHT ASCAT AND WINDSAT DATA SHOWED FRESH TRADE WIND FLOW S 
OF THE HIGH PRES FROM THE ITCZ TO 20N W OF 125W. A LONG WAVE 
TROUGH EXTENDS FROM SOUTHERN CALIFORNIA TO UPPER CLOSED LOW NEAR 
15N138W. LARGE SCALE UPPER DIVERGENCE IS PROMOTING VERTICAL 
MOTION E-SE OF THE UPPER TROUGH. COMBINED WITH LOW LEVEL TRADE 
WIND CONVERGENCE...THIS IS ENHANCING SCATTERED MODERATE 
CONVECTION N OF THE ITCZ BETWEEN 125W AND 130W. GLOBAL MODELS 
HINT OF A WEAK SURFACE TROUGH FORMING ALONG THE ITCZ NEAR 130W S 
OF 15N SE OF THE UPPER TROUGH THROUGH 48 HOURS...ALLOWING A 
SLIGHT INCREASE IN CONVECTION AND LOCALLY HIGHER TRADE WINDS TO 
25 KT NEAR THE SURFACE TROUGH AXIS. A COLD FRONT WILL APPROACH 
THE NW DISCUSSION AREA THROUGH EARLY WED...THEN STALL AND BECOME 
DIFFUSE. MEANWHILE NW SWELL WITH HEIGHTS TO 12 FT AND PERIODS TO 
14 SECONDS WILL MOVE THROUGH MOST OF THE AREA W OF 
110W...FOLLOWED BY A SECOND TRAIN OF NW SWELL MOVING INTO THE NW 
DISCUSSION AREA BY 24 HOURS.

GULF OF TEHUANTEPEC...A STRONG 1038 MB HIGH PRES IS BUILDING 
OVER SOUTHERN TEXAS BEHIND A COLD FRONT THAT PUSHED THROUGH THE 
GULF OF MEXICO YESTERDAY. THE RESULTING STRONG PRES GRADIENT AND 
COLD AIR ADVECTION OVER THE WESTERN GULF OF MEXICO IS PROMOTING 
STORM FORCE WINDS THROUGH THE GULF OF TEHUANTEPEC. GAP WINDS IN 
EXCESS OF 20 KT EXTEND AS FAR AS 500 NM SW OF TEHUANTEPEC...WITH 
SEAS BUILDING TO 23 FT IN THE AREA TO STORM FORCE WINDS. STORM 
CONDITIONS WILL PERSIST THROUGH TONIGHT. WINDS WILL DROP BELOW 
GALE FORCE BY LATE WED...BUT WILL PERSIST TO 30 KT THROUGH AT 
LEAST 72 HOURS...ESPECIALLY DURING THE EARLY MORNING HOURS. 

GULFS OF FONSECA AND PAPAGAYO... STRONG EASTERLY GRADIENT FLOW 
ALONG WITH OVERNIGHT DRAINAGE EFFECTS WILL ENHANCE GAP FLOW 
THROUGH THE GULF OF PAPAGAYO...REACHING GALE FORCE TUE NIGHT 
INTO EARLY WED MORNING...WITH STRONG FLOW EXTENDING 200 NM WSW 
OF THE PAPAGAYO AREA WITH SEAS BUILDING TO 12 FT. FURTHER 
N...OVERNIGHT DRAINAGE IMPACTS ALONG WITH 20 TO 25 KT NORTHERLY 
GRADIENT FLOW ACROSS NORTHERN CENTRAL AMERICA WILL ALLOW WINDS 
TO INCREASE TO 20 KT...AND MERGE WITH GAP FLOW FROM THE GULF OF 
PAPAGAYO.

GULF OF PANAMA...STRONG NORTHERLY GRADIENT FLOW OVER THE SW 
CARIBBEAN WILL PUSH ACROSS THE PANAMA ISTHMUS INTO THE GULF OF 
PANAMA THROUGH WED.

ELSEWHERE E OF 110W...BUILDING N TO NE SWELL ASSOCIATED WITH THE 
COMBINED STRONG GAP FLOW FROM PAPAGAYO AND TEHUANTEPEC WILL 
COVER MUCH OF THE AREA S OF 15N BETWEEN 85W AND 110W. NW SWELL 
WILL PUSH INTO THIS AREA BY 72 HOURS.

GULF OF CALIFORNIA...HIGH PRES WILL BUILD OVER THE GREAT BASIN 
TONIGHT...SUPPORTING FRESH NW FLOW DOWN THE LENGTH OF THE GULF 
THROUGH WED.

$$
CHRISTENSEN