000
AXPZ20 KNHC 050334
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC THU JAN 05 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 AXIS EXTENDS FROM 05N77W TO 04N79W TO 06N87W. 
THE ITCZ AXIS EXTENDS FROM 06N87W TO 08N120W TO BEYOND 04N140W. 
SCATTERED MODERATE CONVECTION WAS NOTED WITHIN 120 NM N OF ITCZ 
AXIS BETWEEN 110W AND 120W.          

...DISCUSSION...

W OF 110W...A 1028 MB HIGH PRES CENTERED NEAR 34N130W WILL 
DISSIPATE OVERNIGHT AS A COLD FRONT STALLS OVER THE FAR NW 
PART OF THE AREA. THE FRONT WILL BECOME DIFFUSE OVERNIGHT...AS 
STRONGER HIGH PRES BUILDS N OF THE AREA THROUGH THU. THE 
PRESSURE GRADIENT BETWEEN THE AREA OF HIGH PRESSURE AND LOWER 
PRESSURE IN THE VICINITY OF THE ITCZ IS MAINTAINING FRESH TRADE 
WIND FLOW FROM 06N TO 20N W OF 128W. SEAS OF 8 TO 10 FT... 
PRIMARILY IN NW SWELL COVERS MUCH OF THE AREA W OF 115W. AN AREA 
OF CONFUSED SEAS WILL PREVAIL S OF 15N BETWEEN 110W AND 120W 
THROUGH FRI AS THE NW SWELL MIXES WITH NE AND E SWELL MIGRATING 
INTO THE AREA. ANOTHER ROUND OF NW SWELL HAS PUSHED INTO THE FAR 
NW PART OF THE DISCUSSION AREA...WITH COMBINED SEAS NEAR 20 FT. 
THE SWELLS WILL SLOWLY SUBSIDE TO 13 FT WHILE SPREADING SE TO 
COVER MUCH OF THE AREA W OF 115W BY FRI NIGHT. 

GULF OF TEHUANTEPEC...THE STRONG HIGH PRES OVER THE WESTERN GULF 
OF MEXICO HAS WEAKENED AND SHIFTED EAST...ALLOWING THE SURGE OF 
COLD AIR INTO THE CHIVELA PASS TO DIMINISH. WINDS TO GALE FORCE 
WILL STILL CONTINUE THROUGH THE OVERNIGHT HOURS DUE TO THE 
RELATIVE DIFFERENCE IN AIR DENSITY BETWEEN THE AIRMASS OVER THE 
GULF OF MEXICO AND THAT OVER THE EASTERN PACIFIC. OVERALL WIND 
SPEEDS ARE TRENDING DOWNWARD THROUGH THE GULF OF 
TEHUANTEPEC...ALTHOUGH MAY GET SOME MINOR SUPPORT OVERNIGHT DUE 
TO DRAINAGE EFFECTS. WINDS TO 30 KT ARE STILL LIKELY THU...THEN 
WILL DIMINISH FURTHER TO BELOW 20 KT BY LATE FRI AS THE AIRMASS 
N OF THE AREA MODIFIES FURTHER. 

GULF OF PAPAGAYO...STRONG EASTERLY GRADIENT WIND OVER THE 
WESTERN CARIBBEAN IS FLOWING THROUGH THE GAP IN THE MOUNTAINS 
OVER NICARAGUA INTO THE GULF OF PAPAGAYO. WINDS HAVE DIMINISHED 
BELOW GALE FORCE....AND WILL CONTINUE TO DIMINISH TO 20 KT 
THROUGH FRIDAY. 

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

ELSEWHERE E OF 110W...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 90W AND 110W. NW SWELL WILL PUSH INTO 
THIS AREA THROUGH 48 HOURS.

GULF OF CALIFORNIA...1040 MB HIGH PRES OVER THE GREAT BASIN IS 
SUPPORTING FRESH NW FLOW DOWN THE LENGTH OF THE GULF AS DEPICTED 
BY THE LATEST 1730 ASCAT PASS. THIS AREA OF HIGH PRESSURE WILL 
WEAKEN THROUGH THU WHICH WILL DIMINISH WINDS BELOW 20 KT BY THU 
NIGHT. 

$$
AL