000
AXPZ20 KNHC 212106
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1850 UTC Sun Jan 21 2018

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... 

A surface trough extends from 07N78W to 05N87W to 05N95W. The 
ITCZ continues from 05N95W to 07N103W to 07N110W to 09N125W to 
09N128W to beyond 09N140W. Scattered moderate isolated strong 
convection was noted from 04N to 07N between 79W and 85W. 
Scattered moderate isolated strong convection was noted from 08N 
to 13N between 110W and 116W. 

...DISCUSSION...
 
OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Gulf of Tehuantepec: Strong winds are expected to develop Monday
night, increasing to near gale force Tuesday. The strong to near
gale winds will prevail through the week, before diminishing 
Friday.

Gulf of California: Fresh to strong winds are expected across 
the central and southern portions of the Gulf starting this 
evening and prevailing through Tuesday before diminishing 
midweek.

Subsiding NW swell continues to keep seas in the 8 to 11 ft 
range off the coast of the Baja California Peninsula. This large 
swell is producing high surf along coasts and outer reefs of Baja
California and mainland Mexico. While seas will slowly subside 
the next couple of days, they are still expected to remain above 
8 ft over this area into the middle of the week. A fresh set of
NW swell will propagate into the waters off the coast of Baja
California Norte Thu night. Seas associated to this swell will
peak near 13 ft Friday. 

OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND 
WITHIN 750 NM OF ECUADOR... 

Nocturnal winds will pulse to fresh each night over the Gulf of 
Papagayo through Mon night and will then pulse to strong each 
night through Thu night. Elsewhere N of 09N, light to gentle 
offshore flow will prevail. Gentle southerly winds will prevail S
of 09N for the next few days. 

REMAINDER OF THE AREA...

High pressure of 1032 mb is centered just north of the area near
32N130W. The pressure gradient between this area of high 
pressure and lower pressure in the vicinity of the ITCZ is 
supporting fresh to strong winds from 10N to 21N and west of 
121W. Combined seas 12 ft or greater prevail within this region 
of strong tradewinds, primarily from 15N to 20N west of 130W in 
a mix of long period NW swell and short period NE wind waves. 
Seas 8 ft or greater cover nearly all the the open waters N of 
05N and west of 103W. Fresh to strong trades will prevail north 
of the ITCZ to around 20N for the next couple of days as high 
pressure remains north of the forecast waters. Areal coverage of 
the fresh to strong trades will diminish by midweek as the area 
of high pressure weakens and a cold front approaches the NW 
waters. High pressure building behind the cold front will once 
again increase coverage of the fresh to strong trades Thursday. 
   
$$
AL