000
AXPZ20 KNHC 141535
TWDEP

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1535 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 1200 UTC surface analysis and satellite imagery through
1500 UTC.

...SPECIAL FEATURES...

Hurricane Darby centered near 15.9N 116.9W at 1500 UTC moving
west or 280 deg at 11 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 northeast and 90
nm southwest semicircles. 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 20.8N 136.7W at 1500 UTC
moving west-northwest or 295 deg at 12 kt. Maximum sustained
winds 45 kt with gusts to 55 kt. Estimated minimum central
pressure 1000 mb. Scattered moderate convection is within 90 nm
in the northeast 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 currently covering the area
within 270 nm north and 150 nm south of the storm will diminish
through Friday as well. 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 103W.
Scattered moderate convection is noted north of 13N between 98W
and 105W. 1010 mb low pressure is starting to develop near the
intersection of the tropical wave and the monsoon trough. Environmental
conditions will be favorable for tropical cyclogenesis over the
next couple of days. See latest NHC tropical weather outlook for
the eastern Pacific under AWIPS/WMO headers MIATWOEP/ABPZ20 KNHC
for more details.

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

The monsoon trough extends from 08N78W to 08N80W to 08N85W to
08N95W to 11N102W. Scattered moderate convection is observed
within 210 nm south of the monsoon trough east of 100W.

...DISCUSSION...   

A ridge extends from 1032 mb high pressure centered near 42N139W
southeast to near 25N115W. 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. Looking ahead, high
pressure developing over the northern Gulf of Mexico will support
enhanced Tehuantepec Gap winds by early next week.

$$
Christensen