000
AXPZ20 KNHC 040320
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC WED JAN 04 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0300 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS FROM 05N77W TO 07N85W TO 05N93W. THE 
ITCZ AXIS EXTENDS FROM 05N93W TO 06N100W TO 05N106W TO 07.5N121W 
TO BEYOND 04N140W. SCATTERED MODERATE CONVECTION WAS NOTED 
WITHIN 90 NM N OF ITCZ AXIS BETWEEN 98W AND 104W. SCATTERED 
MODERATE CONVECTION WAS NOTED WITHIN 120 NM N OF ITCZ AXIS 
BETWEEN 111W AND 127W.  

...DISCUSSION...
W OF 110W...A 1026 MB HIGH PRES IS CENTERED NEAR 33N127W WITH 
SURFACE RIDGE EXTENDING SE TO NEAR 17N106W. THE PRESSURE 
GRADIENT BETWEEN THIS AREA OF HIGH PRESSURE AND LOW PRESSURE IN 
THE VICINITY OF THE ITCZ IS PRODUCING FRESH TRADEWIND FLOW FROM 
06N TO 12N W OF 128W. A COLD FRONT WILL APPROACH THE NW PART OF 
THE DISCUSSION AREA THROUGH EARLY WED...THEN STALL AND BECOME 
DIFFUSE. THOUGH THE FRONT WILL BECOME DIFFUSE BEFORE ENTERING 
THE FORECAST AREA LARGE LONG PERIOD NW SWELL WILL MOVE INTO THE 
NW PART OF THE AREA WED MORNING...WITH SEAS TO 18 FT. MEANWHILE 
EXISTING NW SWELL WITH HEIGHTS TO 13 FT AND PERIODS TO 14 
SECONDS WILL CONTINUE TO MOVE THROUGH MOST OF THE AREA W OF 110W.

GULF OF TEHUANTEPEC...NORTHERLY FLOW OVER THE GULF OF MEXICO IS 
FUNNELING THROUGH THE CHIVELA PASS PROMOTING STRONG GALE FORCE 
WINDS TO 45 KT OVER THE GULF OF TEHUANTEPEC. GAP WINDS IN EXCESS 
OF 20 KT ARE REACHING AS FAR W AS 109W...WITH SEAS TO 20 FT IN 
THE AREA OF GALE FORCE WINDS. WINDS TO MINIMUM GALE FORCE WILL 
PREVAIL THROUGH THU MORNING. 

GULFS OF FONSECA AND PAPAGAYO... STRONG EASTERLY GRADIENT FLOW 
ALONG WITH OVERNIGHT DRAINAGE EFFECTS WILL ENHANCE GAP FLOW 
THROUGH THE GULF OF PAPAGAYO...WITH WINDS REACHING GALE FORCE 
DURING THE OVERNIGHT HOURS. WINDS WILL DIMINISH BELOW GALE FORCE 
BY WED EVENING. FRESH TO STRONG WINDS WILL CONTINUE THROUGH AT 
LEAST THU EVENING OVER THE GULF OF PAPAGAYO AREA WITH SEAS 
BUILDING TO 12 FT. FURTHER N...THIS AFTERNOONS ASCAT PASS 
INDICATES WINDS HAVE FRESHENED OVER THE GULF OF FONSECA. THESE 
WINDS ARE MERGING WITH THE WINDS FUNNELING INTO 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 EARLY THU.

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. THE SWELL 
WILL REACH TO 115W BY THU WHERE IT WILL MIX WITH NW SWELL 
BETWEEN 110W AND 115W. 

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

$$
AL