000
AXPZ20 KNHC 140907
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
444 UTC Thu Jul 14 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 0600 UTC surface analysis and satellite imagery through
0900 UTC.

...SPECIAL FEATURES...

Hurricane Darby centered near 15.7N 115.5W at 0900 UTC moving
west or 275 deg at 10 kt. Maximum sustained winds 70 kt with
gusts to 85 kt. Estimated minimum central pressure 989 mb.
Numerous strong convection is noted within 60 nm east and 30 nm
west semicircles, with scattered moderate convection elsewhere
from 13N to 17N between 113W and 117W. Hurricane Darby will
continue to intensify as it moves west over the next several days.
See latest NHC forecast advisory under AWIPS/WMO headers
MIATCMEP5/WTPZ25 KNHC for more details. Also see latest high seas
forecast HSFEP2/FZPN03 for more details on the wave forecasts
associated to Darby.

Tropical Storm Celia centered near 20.3N 135.8W at 0900 UTC
moving west-northwest or 295 deg at 11 kt. Maximum sustained
winds 45 kt with gusts to 55 kt. Estimated minimum central
pressure 1000 mb. Scattered moderate convection is within 180 nm
in the north semicircle. Celia is expected to continue to weaken
as the system shifts west of the area Friday. The large area of
strong winds and high seas covering the NW waters will decrease.
by Friday night, winds over forecast waters will diminish to 20 kt
or less and seas subside to less than 8 ft. See latest NHC
forecast advisory under AWIPS/WMO headers MIATCMEP4/WTPZ24 KNHC
for more details. Also see latest high seas forecast HSFEP2/FZPN03
for more details on the wave forecasts associated to Celia.

The axis of a tropical wave is noted north of 07N near 101W.
Scattered moderate isolated strong convection is noted north of
14N between 97W and 102W. Low pressure will develop along the
intersection of this tropical wave and the monsoon trough today.
This low pressure area will be one to watch with interest over
the next couple of days as environmental conditions will be
favorable for tropical cyclogenesis.

..INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

The monsoon trough extends from 08N79W to 09N92W to 11N106W.
Scattered moderate convection is observed within 180 nm south of
the monsoon trough east of 96W.

...DISCUSSION...   

High pressure of 1032 mb centered near 43N137W extends a ridge
southeast to near 24N114W. The pressure gradient between this
ridge and lower pressure over Mexico will support moderate to
occasionally fresh southerly flow across the Gulf of California.
The pressure gradient between the ridge and Celia is supporting
fresh to strong trade winds north of Celia and west of 130W.
Mainly moderate winds prevail elsewhere north of 20N.

Both Celia and Darby are supporting large seas across our area of
discussion. As Celia weakens, the areal coverage of large seas
will slowly decrease. Darby will continue to intensify with an
expanding area of large seas and high winds over the next few
days. Looking ahead, northerly swell with wave heights to 9 ft are
expected to push as far south as 25N west of 120W by late
Saturday, mixing with seas generated on the northern edge of
Darby.

Winds will pulse over the Gulf of Papagayo over the next couple of
days. Winds will peak near 20 kt during overnight hours with the
added component of nocturnal drainage flow. High pressure
developing over the northern Gulf of Mexico will support enhanced
Tehuantepec Gap winds by early next week.

$$
AL