000
AXPZ20 KNHC 170241
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 UTC Sat Sep 17 2016

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
0200 UTC.

...SPECIAL FEATURES...

Post-Tropical Cyclone Orlene 1006 mb centered near 20.1N 127.7W
at 0300 UTC moving W at 8 kt. Maximum sustained winds are 30 kt
with gusts to 40 kt. The low level circulation is fully exposed
and lacks deep convection. See final NHC forecast/advisory under
AWIPS/WMO headers MIATCMEP1/WTPZ21 KNHC for more details.

A broad area of low pressure 1007 mb centered near 14N105W has a
high probability of becoming a tropical cyclone within the next
48 hours. Active convection is within 180 to 240 nm northeast of
the low center. A gale warning is in effect for Sunday, in
anticipation of increased winds associated with this low. See
the latest high seas forecast under AWIPS/WMO headers
MIAHSFEP2/FZPN03 KNHC for more details.

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

The monsoon trough axis extends from 09N84W to 1007 mb low pres
near 14N105W to 11N109W to 09N140W. Scattered moderate isolated
strong convection from 14N to 17N between 101W and 106W.

...DISCUSSION...   

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

A surface ridge extending from 35N145W to near the southern tip
of Baja California is supporting moderate northwest winds west
of Baja California and seas of 4 to 6 ft. Winds will diminish
this weekend, with gentle to moderate winds prevailing west of
Baja California. A surface trough over the Baja peninsula will
maintain light to gentle winds in the Gulf of California through
the weekend. The low pressure area centered near 14N105W will
move northwestward and increase in organization the next couple
of days, inducing gale force winds in portions of the offshore
zones around 19N Sunday. The gale winds are expected to continue
as this system becomes a tropical cyclone and moves northward
west of southern Baja California.

In the Gulf of Tehuantepec, moderate to fresh north winds will
pulse during overnight and early morning hours Sunday through
Tuesday. N winds could become strong Tuesday night through early
Wednesday morning.

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

Light to gentle winds are expected through early next week north
of 05N. Mainly moderate SW to W winds are expected over waters
south of 05N. Combined seas of 4 to 6 ft are likely across the
entire area through the weekend into next week as long period
cross-equatorial southwest swell propagates northward. Scattered
showers and isolated thunderstorms are possible at night over
the offshore waters.

REMAINDER OF THE AREA... 

The ridge over the northern waters will support mainly fresh
trades through Saturday N of 14N and W of 128W, and support 8-9
ft seas from 10N to 20N W of 130W through Saturday. Winds and
seas will diminish Sunday as the ridge weakens. Strong winds and
large swell are likely over the open Pacific waters west of the
offshore zones Sunday through Tuesday.

$$
Mundell