AXPZ20 KNHC 272144

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2205 UTC Wed Jul 27 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 1800 UTC surface analysis and satellite imagery through
2130 UTC.


Tropical Storm Frank is centered near 23.1N 121.8W, or about 755
miles...1215 km W of the Southern tip of the Baja California
Peninsula, at 2100 UTC Jul 27, moving WNW or 295 degrees at 9
kt. The maximum sustained winds have diminished to 50 kt with
gusts to 60 kt. The estimated minimum central pressure has risen
to 999 mb. Currently, scattered moderate isolated strong
convection is observed within 75 nm in the southwest semicircle
of the storm. Frank is expected to weaken to a remnant low
within 24 hours. Refer to the latest NHC forecast advisory under
AWIPS/WMO headers MIATCMEP2/WTPZ22 KNHC for more details.

Also refer to the latest high seas forecast under AWIPS/WMO
headers MIAHSFEP2/FZPN03 KNHC for more details on the wave
forecasts associated with Frank.


A tropical wave is analyzed from 10N to 18N along 110/111W, and
has been moving W at about 10 kt. Isolated moderate to strong
convection is noted from 10-15N within 120 nm east of the wave

Scattered moderate isolated strong convection is observed within
240 nm over the n semicircle, and within 120 nm over the SW
semicircle of a 1009 mb low pressure center embedded in the
monsoon trough near 11N109W. This low has a medium chance of
developing into a tropical cyclone within 5 days.

The post-tropical remnant low of Georgette was centered near
20N130W moving WNW at 8 kt. The maximum sustained winds are
estimated to have dropped off to 25 kt, with ASCAT A and B
passes from 1804 and 1858 UTC indicating 20 to 25 knot winds
within 120 nm in the N semicircle of the remnant low. The
remnant low of Georgette is expected to continue to weaken, and
should dissipate within 36 hours.


A monsoon trough extends nw from the pacific coast of Colombia
at 09N84W to 10N100W to 1009 MB Low Pressure near 10N109W to
11N123W. The axis of the ITCZ extends from 13N138W to 13N140W.
Scattered moderate isolated strong convection was noted within
120 NM of the axis between 100W and 103W. Scattered moderate
convection was noted within 90-120 NM of the axis between 118W
and 123W.


N of 15N e of 120W:

Tropical storm force winds associated with Frank are moving west
of 120W, and associated seas of 8 ft or greater will shift west
of 120W this evening. See special features above additional
information on Frank.

A west to east orientated surface ridge will build from 21N120W
to 15N106W on Thu in the wake of tropical storm Frank. The weak
gradient northeast of the ridge will support light to gentle nw
winds through the upcoming weekend, with seas of 4-6 ft.

A nnw to sse orientated trough will meander e and w over the
Baja California Peninsula, and the northern Gulf of California
this week, supporting light and variable winds across the Gulf
of California waters through early Fri. A gentle to moderate
southerly flow is expected to begin late Fri, and will persist
through early Sat night across the gulf waters.

Moderate northerly flow is expected across the Gulf of
Tehuantepec late Thu night into the early daylight hours on Fri,
and then again late Fri night into Sat morning with seas
building to about 6 ft. Model guidance is suggesting a slightly
stronger drainage flow on Mon night into Tue morning with fresh
to locally strong n-ne winds, and seas building to 8 ft.

S of 15N e of 120W:

See section on tropical wave and a surface low.

Fresh NE to E winds are expected across, and just downstream of
the Gulf of Papagayo during the overnight hours tonight, then
guidance is hinting at moderate to locally fresh easterly
drainage flow on Thu night as a weak surface low develops near
09N91W. The low should move westward through the upcoming

Long-period cross-equatorial SW swell, in the form of combined
seas of 6-8 ft, is forecast to propagate n across the equator
between 100-115W on Thu, and reach along 08N between 90-115W by
late Fri, then begin to subside. Combined seas are forecast to
less than 8 ft on Sat night.

W of 120W:

See section above for information on the remnant low of
Georgette and Tropical Storm Frank that will pass westward
through the northern portion of this discussion area into this
upcoming weekend. Combined seas of 6-9 ft, primarily due to
mixing swell, are expected to surround the large seas near the
cyclone, and cover the waters elsewhere to the n of 12N through
the upcoming weekend.