AXPZ20 KNHC 271549
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1605 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
Based on 1200 UTC surface analysis and satellite imagery through
Tropical Storm Frank is centered near 22.7N 120.8W, or about 695
miles w of the southern tip of the Baja California Peninsula, at
1500 UTC Jul 27, moving wnw, or 290 degrees at 10 kt. The
maximum sustained winds have diminished to 55 kt with gusts to 65
kt. The estimated minimum central pressure has risen to 996 mb.
Currently, scattered moderate isolated strong convection is
observed within 45 nm either side of a line from 22N120W to
25N122W. Frank is expected to weaken to a remnant low press in
48 hours. Refer to the latest NHC forecast advisory under
AWIPS/WMO headers MIATCMEP2/WTPZ22 KNHC for more details.
Georgette weakened to a Tropical Depression at 1200 UTC Jul 21.
At 1500 UTC, the remnant low of Georgette was near 19.5N
129.7W...or about 1295 miles w of the southern tip of the Baja
California Peninsula. The low is moving wnw, or 300 deg at 8 kt.
The maximum sustained winds have diminished to 30 kt, with gusts
to 40 kt near the center. The estimated minimum central pressure
has risen to 1007 mb. Scattered showers are noted within 30 nm se,
and within 90 nm nw of the center. Scattered moderate convection
is observed well nw of the center within 60 nm of 23N135W. The
remnant low of Georgette is expected to continue to weaken, and
should dissipate within 72 hours. Refer to the latest NHC forecast
advisory under AWIPS/WMO headers MIATCMEP3/WTPZ23 KNHC for more
Also refer to the latest high seas forecast under AWIPS/WMO
headers MIAHSFEP2/FZPN03 KNHC for more details on the wave
forecasts associated with these systems.
...TROPICAL WAVE AND TROPICAL LOW...
A tropical wave is analyzed from 10N to 18N along 107.5W, and has
been moving W at about 10 kt. Isolated moderate to strong
convection is noted from 10-15N within 120 nm either side of the
wave axis. Expect this tropical wave to lose identity over the
next day or so.
Scattered moderate isolated strong convection is observed within
60 nm over the n semicircle, and within 210 nm over the s
semicircle of a 1009 mb low pressure center embedded in
the monsoon trough near 09N105W. This low has a good chance of
developing into a tropical cyclone in 3 to 5 days.
..INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
A monsoon trough extends nw from the pacific coast of Colombia
at 08N78W to 11N93W, then turns sw through an embedded 1009
mb low pres at 09N105W, then turns nw to 10N113W where it loses
identity. The ITCZ forms sw of the Georgette near 13N138W and
continues w to beyond 13N140W. Scattered moderate isolated
strong convection is observed s of Panama, to the e of a line
from 03N79W to 08N82W to the pacific coast of Colombia. Similar
convection is noted along the monsoon trough within 120 nm of
09N97W, within 180 nm either side of a line from 09N108W to
10N118W to 07N128W.
N of 15N e of 120W:
Tropical storm force winds associated with tropical cyclone
Frank will soon move west of 120W, and associated seas of 8 ft
or greater will shift w of 120W early tonight. 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 cyclone Frank. The
weak gradient northeast of the ridge will support light to
gentle nw winds through the upcoming weekend, with seas of 4-6
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 to locally strong ne-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
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 special features above for information on the remnants 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.