000
AXPZ20 KNHC 092138
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
2205 UTC THU JAN 09 2014

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...              

MONSOON TROUGH EXTENDS FROM 09N84W TO 07N88W TO 04N92W. ITCZ 
CONTINUES FROM 04N92W TO 06N120W TO BEYOND 08N140W. SCATTERED 
MODERATE CONVECTION IS NOTED WITHIN 120 NM N OF ITCZ W OF 137W. 
 
...DISCUSSION... 

GULF OF TEHUANTEPEC...THE 1522 ASCAT PASS SHOWED NORTHERLY WINDS 
OF 20 TO 30 KT ACROSS THE GULF OF TEHUANTEPEC. SO...THE GALE 
WARNING WAS ALLOWED TO EXPIRE AT 1800 UTC. THIS STRONG GAP WIND 
EVENT HAS PRODUCED A LARGE AREA OF NORTHERLY SWELL PROPAGATING 
SOUTHWARD FROM THE TEHUANTEPEC COAST WITH AN AREA OF 8 TO 10 FT 
SEAS AFFECTING THE WATERS FROM THE EQUATOR TO 13N BETWEEN 95W 
AND 115W. THE SWELLS WILL TRANSLATE WESTWARD AND SHRINK TO AN 
AREA FROM 03N TO 10N BETWEEN 105W AND 115W BY OVERNIGHT THU INTO 
FRI. BY LATE FRI...SEAS ARE FORECAST TO BE LESS THAN 8 FT ACROSS 
MOST OF THE AREA E OF 110W. 

HIGH PRESSURE OF 1030 MB CENTERED N OF THE AREA NEAR 34N135W 
EXTENDS A RIDGE SE TO NEAR THE REVILLAGIGEDO ISLANDS. THE 
PRESSURE GRADIENT BETWEEN THE AREA OF HIGH PRESSURE AND LOWER 
PRESSURE IN THE VICINITY OF THE ITCZ IS MAINTAINING AN AREA OF 
FRESH TO STRONG TRADES FROM 08N TO 21N W OF 130W...AND FROM 08N 
TO 15N BETWEEN 125W AND 130W WITH SEAS TO 11 FT. SCATTEROMETER 
DATA CONFIRMED THE PRESENCE OF THESE WINDS. THE AREA OF HIGH 
PRESSURE WILL REMAIN NEARLY STATIONARY WHILE BUILDING OVER THE 
NEXT 48 HOURS. THIS WILL INCREASE THE AREA OF FRESH TO STRONG 
TRADES...COVERING MUCH OF THE FORECAST REGION N OF THE ITCZ AND 
W OF 125W BY FRI. 

HIGH PRESSURE RIDGING DOWN THE EASTERN GULF OF MEXICO WAS 
ENHANCING THE GAP FLOW THROUGH THE GULFS OF PAPAGAYO AND 
FONSECA. NWP GUIDANCE SUGGESTS PULSING WINDS OF 20-25 KT ACROSS 
THE GULF OF PAPAGAYO DURING THE OVERNIGHT AND EARLY MORNING 
HOURS WITH THE AID OF DRAINAGE FLOW. SEAS WILL BUILD DOWNSTREAM 
TO AROUND 9 FT.
 
$$
GR