000
AXPZ20 KNHC 052110
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

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

THE MONSOON TROUGH AXIS EXTENDS FROM 06N77W TO 07.5N82W TO 
05.5N90W. THE ITCZ AXIS EXTENDS FROM 05.5N90W TO 08N125W TO 
BEYOND 05N140W. SCATTERED MODERATE CONVECTION WAS NOTED WITHIN 
90 NM OF AXIS FROM 105W TO 110W. SCATTERED MODERATE CONVECTION 
WAS NOTED WITHIN 90 NM OF AXIS BETWEEN 125W AND 130W.

...DISCUSSION...

W OF 110W...1037 MB HIGH PRES IS CENTERED NEAR 39N133W WITH 
RIDGE EXTENDING SE TO NEAR 19N109W. THE PRESSURE GRADIENT 
BETWEEN THE AREA OF HIGH PRESSURE AND LOWER PRESSURE IN THE 
VICINITY OF THE ITCZ IS MAINTAINING FRESH TO STRONG TRADE WIND 
FLOW FROM 07N TO 20N W OF 128W AND FROM 09N TO 15N BETWEEN 118W 
AND 128W. SEAS TO 18 FT IN LONG PERIOD NW SWELL IS CURRENTLY 
AFFECTING THE NW PART OF THE FORECAST AREA. THESE SWELLS WILL 
CONTINUE TO SPREAD SE WHILE SLOWLY SUBSIDING...WITH SEAS 8 TO 13 
FT COVERING MUCH OF THE AREA W OF 110W BY SAT. 

GULF OF TEHUANTEPEC...THOUGH WINDS OVER THE GULF OF MEXICO HAVE 
VEERED...WINDS CONTINUE TO FUNNEL THROUGH THE CHIVELA PASS INTO 
THE GULF OF TEHUANTEPEC DUE TO THE RELATIVE DIFFERENCE IN AIR 
DENSITY BETWEEN THE AIRMASS OVER THE GULF OF MEXICO AND THAT 
OVER THE EASTERN PACIFIC. THIS IS RESULTING IN WINDS TO NEAR 
GALE OVER THE GULF OF TEHAUNTEPEC. AS THE AIR MASS TO THE N OF 
THE AREA CONTINUES TO MODIFY...WIND SPEEDS WILL CONTINUE TO 
TREND DOWNWARD THROUGH THE GULF OF TEHUANTEPEC...WITH WINDS 
EXPECTED TO DIMINISH FURTHER TO BELOW 20 KT BY FRI EVENING. 

GULF OF PAPAGAYO...FRESH TO STRONG EASTERLY GRADIENT WIND OVER 
THE WESTERN CARIBBEAN IS FLOWING THROUGH THE GAP IN THE 
MOUNTAINS OVER NICARAGUA INTO THE GULF OF PAPAGAYO. 

ELSEWHERE E OF 110W...N TO NE SWELL ASSOCIATED WITH THE COMBINED 
STRONG GAP FLOW FROM PAPAGAYO AND TEHUANTEPEC COVERS MUCH OF THE 
AREA S OF 15N BETWEEN 90W AND 120W. THESE SWELLS ARE MIXING WITH 
NW SWELL W OF 110W.

$$
AL