000
AXPZ20 KNHC 210332
TWDEP 

TROPICAL WEATHER DISCUSSION                              
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
0405 UTC WED JAN 21 2015

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 06N77W TO 07N83W TO 05N100W TO 
05N110W. THE ITCZ CONTINUES FROM 05N110W TO 09N129W TO BEYOND 
06N140W. A CLUSTER OF SCATTERED MODERATE TO ISOLATED STRONG 
CONVECTION IS FROM 05N TO 07N BETWEEN 85W AND 87W. SCATTERED 
MODERATE CONVECTION CAN BE FOUND FROM 02N TO 05N BETWEEN 82W AND 
85W. SIMILAR CONVECTION IS FROM 03N TO 06N BETWEEN 91W AND 95W.

...DISCUSSION... 

ALOFT...A TROUGH/RIDGE/TROUGH PATTERN DOMINATES THE FORECAST 
REGION W OF 110W. A RIDGE IS NOTED E OF 110W OVER SE MEXICO AND 
CENTRAL AMERICA AND THE EPAC WATERS. ABUNDANT MID/UPPER LEVEL 
MOISTURE IS AHEAD OF THE FIRST TROUGH THAT EXTENDS FROM 30N128W 
TO 20N135W TO BEYOND 13N140W AND COVERS ROUGHLY THE AREA N OF 
20N BETWEEN 120W AND 134W. 
                                 
HIGH PRES LOCATED N OF AREA EXTENDS A RIDGE SE ACROSS THE N 
WATERS TO NEAR 19N110W. MODERATE TO FRESH WINDS ARE NOTED PER 
SCATTEROMETER DATA BETWEEN THE RIDGE AND A SURFACE TROUGH 
LOCATED ALONG 137W FROM 16N TO 22N. MOSTLY GENTLE TO MODERATE 
WINDS CAN BE FOUND ELSEWHERE UNDER THE INFLUENCE OF THE RIDGE. 
FARTHER SOUTH...ANOTHER SURFACE TROUGH IS ANALYZED FROM 10N138W 
TO 06N139W. AN EARLIER ASCAT PASS SHOWED THE WINDS SHIFT 
ASSOCIATED WITH THIS TROUGH AS WELL AS MODERATE TO FRESH WINDS 
ON EITHER SIDE OF THE TROUGH AXIS. VISIBLE SATELLITE IMAGERY 
REVEALS A SWIRL OF LOW CLOUDS NEAR THE SOUTHERN END OF THE 
TROUGH THAT WILL CONTINUE TO MOVE WESTWARD.

SEAS WILL CONTINUE TO SUBSIDE ACROSS THE WATERS W OF 110W 
TONIGHT AND WED. A NEW SET OF LONG PERIOD NW SWELL WILL SWEEP 
INTO THE NW PART OF THE AREA THU MORNING...WITH SEAS RAPIDLY 
BUILDING TO 14-15 FT NEAR 30N140W THROUGH THU NIGHT...THEN 
GRADUALLY SUBSIDE TO 10-11 FT THROUGH SAT.

HIGH PRES BUILDING OVER THE SW CONUS WILL BRING AN INCREASE IN 
WINDS AND SEAS ACROSS THE NORTHERN PART OF THE GULF OF 
CALIFORNIA WED NIGHT INTO THU. WINDS WILL BECOME FRESH TO STRONG 
N OF 30N THU MORNING...THEN SPREAD SOUTHWARD TO ENCOMPASS MOST 
OF THE GULF OF CALIFORNIA THROUGH EARLY FRI. FRESH NW WINDS ARE 
EXPECTED TO PERSIST IN THE REGION THROUGH SAT.

GAP WINDS...                                              
PULSING OF NOCTURNAL WINDS ARE EXPECTED ACROSS THE GULF OF 
PAPAGAYO REACHING 25 KT FROM 0600 TO 1200 UTC WITH SEAS OF 6-7 
FT THROUGH AND DOWNWIND OF THE GULF. A WEAKENING RIDGE ACROSS 
CENTRAL AMERICA SUPPORTS THESE MARINE CONDITIONS. 

FRESH N WINDS WILL PERSIST IN THE GULF OF PANAMA DURING THE 
OVERNIGHT AND EARLY MORNING HOURS THROUGH THU MORNING DUE TO A 
MODERATE PRESSURE GRADIENT ACROSS THE AREA. MAX SEAS OF 6-7 FT 
ARE EXPECTED AT PEAK WINDS DURING THE MORNING HOURS.
 
WINDS IN THE GULF OF TEHUANTEPEC WILL REMAIN LIGHT THROUGH FRI 
NIGHT...THEN INCREASE EARLY SAT AS STRONG HIGH PRESSURE BUILDS 
INTO SOUTHERN MEXICO BEHIND A COLD FRONT FORECAST TO EXTEND FROM 
TAMPA BAY FLORIDA TO THE YUCATAN PENINSULA BY SAT MORNING. 
CURRENTLY....MARINE GUIDANCE SUGGESTS NORTHERLY WINDS OF 35-40 
KT AND BUILDING SEAS TO 15-16 FT WITH THIS GAP WIND EVENT.  
 
$$ 
GR