000
AXPZ20 KNHC 180316
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC WED NOV 18 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.               

...SPECIAL FEATURES...

LOW PRES 1007 MB IS EMBEDDED IN THE MONSOON TROUGH NEAR
12.5N107W. SCATTERED MODERATE TO STRONG CONVECTION IS WITHIN 300
NM IN THE NW SEMICIRCLE OF THE LOW. AN AFTERNOON RAPIDSCAT
SCATTEROMETER PASS INDICATED THAT THE CENTER WAS MORE TO THE E
WITH THE CENTER LOCATED AWAY FROM ANY DEEP CONVECTION. THIS
FEATURE HAS A MEDIUM POTENTIAL FOR TROPICAL CYCLONE DEVELOPMENT
DURING THE NEXT 48 HOURS. 

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

THE MONSOON TROUGH AXIS EXTENDS FROM 09N85W TO LOW PRES NEAR
12N107W TO LOW PRES NEAR 11N25W TO 10N129W. THE ITCZ AXIS
EXTENDS FROM 10N129W TO 09N140W. SCATTERED MODERATE CONVECTION
IS WITHIN 180 NM S OF THE AXIS E OF 96W...WITHIN 150 NM N OF THE
AXIS BETWEEN 113W AND 116W...AND ALSO FROM 11N TO 14N121W.

...DISCUSSION...

GULF OF CALIFORNIA...A STRONG PRESSURE GRADIENT ACROSS MOST OF
THE GULF WILL CONTINUE TO SUPPORT FRESH TO STRONG NW TO N WINDS
AND SEAS UP TO 8 FT. THESE WINDS AND SEAS WILL SPREAD S AND SE
OUT OF THE MOUTH OF THE GULF THROUGH WED IMPACTING THE WATERS
BETWEEN CABO CORRIENTES AND CABO SAN LUCAS. EARLIER
SCATTEROMETER DATA ALSO SHOWED FRESH TO STRONG WINDS FILTERING
THROUGH BAJA CALIFORNIA SUR PASSAGES TO THE SW OF THE PENINSULA.
CONDITIONS WILL GRADUALLY IMPROVE BY THU AS THE PRES GRADIENT
SLACKENS SOMEWHAT.

GULF OF TEHUANTEPEC...LIGHT AND VARIABLE WINDS ARE EXPECTED
THROUGH WED. HIGH PRES WILL THEN BUILD IN BEHIND A COLD FRONT IN
THE WESTERN GULF OF MEXICO N OF THE AREA WHICH WILL INDUCE
ANOTHER ROUND OF FRESH TO NEAR GALE FORCE NORTHERLY WINDS IN 
THE GULF OF TEHUANTEPEC LATE WED NIGHT THROUGH AT LEAST THU
AFTERNOON...LIKELY CONTINUING FOR SEVERAL DAYS INTO THE UPCOMING
WEEKEND. CONDITIONS WILL APPROACH GALE FORCE...HOWEVER CURRENT
MODEL GUIDANCE REMAINS BELOW GALE FORCE THROUGH THE NEXT 48
HOURS.

ELSEWHERE...A STRONG EARLY SEASON COLD FRONT HAD PUSHED S-SE
ACROSS THE DISCUSSION WATERS N OF 20N W OF MEXICO ALTHOUGH THIS
FEATURE HAS SINCE DISSIPATED IN THE PAST SEVERAL HOURS DURING
ITS TREK ACROSS THE HIGH TERRAIN OF CENTRAL MEXICO. A 1033 MB
HIGH LINGERS N OF THE DISCUSSION WATERS NEAR 35N135W WITH
RIDGING BUILDING IN ACROSS THE NW AND N CENTRAL WATERS. THIS
RIDGING COMBINED WITH LOWER PRES ALONG AND ASSOCIATED WITH THE
MONSOON TROUGH AND ITCZ ARE RESULTING IN A TIGHT PRES GRADIENT
ACROSS THE MAJORITY OF THE WATERS N OF THE MONSOON TROUGH/ITCZ
AND W OF 110W. SCATTEROMETER DATA AND SHIP REPORTS INDICATED
FRESH TO STRONG TRADES ACROSS THIS AREA...AND SEAS ARE UP TO 14
FT IN MIXED SWELL. THE PRES GRADIENT WILL GRADUALLY SLACKEN
ALLOWING FOR TRADES TO DIMINISH TO 20 KT OR LESS BY 48 HOURS.
RESULTANT SWELLS WILL THEN BE ALLOWED TO SUBSIDE TO 10 FT OR
LESS BY THEN AS WELL.

AN AREA OF FRESH SW WINDS AND SEAS BUILDING TO AROUND 8 FT IS
OCCURRING OFFSHORE OF CENTRAL AMERICA FROM 05N TO 08N BETWEEN
84W AND 93W. WINDS WILL DIMINISH SLIGHTLY ALLOWING FOR SEAS TO
SUBSIDE TO LESS THAN 8 FT BY LATE WED MORNING.

$$
LEWITSKY