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Area forecast discussion
National Weather Service Houston/Galveston Texas
1156 PM CDT Wed Oct 16 2019

Aviation [06z taf issuance]...

With the exception of lbx and gls which are hanging on the edge of
the cloud deck, dry Post-frontal air is working in and clearing
out the area. Near-MVFR conditions look to persist there a bit
longer thanks to that. Further north, cxo has proved its usual
squirrelly self and has already spent 10 minutes at 2 sm
visibility. It was brief and is already rebounding so not sure
that the influx of drier air will allow for any more crashes, but
will be something to be watched for through dawn.

&&

Previous discussion /issued 614 PM CDT Wed Oct 16 2019/...

Short term...
patchy light rain will persist near the coast through the late
afternoon before getting nudged offshore by the 850 mb front. Low
clouds will eventually mix out but mid/upper level moisture will
remain in place tonight and much of Thursday in response to a
compact upper level low over southwest Texas. This feature will
deepen a bit tonight as it sinks southward. On Thursday, this
upper level feature will get sheared out as it moves east. The
best moisture with this feature appears to be on it's south side,
so not expecting much more than some mid/high level cloud cover. A
weak area of low pressure will try to develop in the SW Gulf on
Thursday. This feature will induce an east-NE wind and raise tide
levels. Could be some minor coastal flooding at high tide on Gulf
facing beaches at high tide. 43



Long term...
an mid to upper level shortwave is expected to move over southeast
Texas Thursday night through early Friday morning, with a much drier
air mass following behind and moving into the region. With the lack
of moisture, low to no chance of showers is expected as it passes
through the local area. Meanwhile, a low pressure system developing
over the Bay of Campeche will move northeastward over the central
Gulf of Mexico Friday and towards Mississippi/Alabama/Florida
Panhandle coastline Friday night. At this time, the general track
maintains the system moving over the Gulf of Mexico and away from
southeast Texas. Thus, direct impacts are currently not expected for
the local area. However, there is a chance the outer region of the
deep tropical moisture will extend into the local waters and coastal
areas. This could allow for additional shower and thunderstorm
activity mainly over the Gulf waters and coastal regions Thursday
night into Friday. Based on the 2 PM tropical weather outlook, the
system has a 50 percent chance of forming into a tropical cyclone
during the next 48 hours. Continue to monitor the latest NHC
forecasts for additional information regarding the development of
this system.

During the weekend, winds will become southerly and allow for
temperatures to gradually rise back into the mid to upper 80s. Low
level moisture will return Sunday and increase chances of showers
throughout the day. Meanwhile, an upper level trough will amplify
over The Rockies and move eastward into the Central Plains by Sunday
night and Monday. A cold front should move across southeast Texas
Monday, increasing shower and thunderstorms activity throughout the
day. Weather conditions should improve by Monday night as a drier
air mass moves into the region behind the front and high pressure
builds over Texas. Winds will become northerly and increase in the
wake of the front and temperatures will cool. Tranquil weather
conditions will prevail for the second half of next week. 24



Marine...
northerly winds will continue to increase this afternoon through
Tuesday morning. Winds around 20 knots and seas of 3 to 7 feet are
expected across the nearshore waters, and winds of 20 to 25 knots
and seas of 4 to 7 feet are expected across the offshore waters.
A Small Craft Advisory will be in effect today at 6 PM CDT through
late tonight. Across the bays, small craft should exercise
caution due to winds of 15 to 20 knots. Winds and seas will
gradually decrease Thursday and should fall below Small Craft Advisory and scec
criteria by Thursday evening.

A low pressure system developing over the Bay of Campeche is
expected to move northeastward across the Gulf of Mexico Friday.
This will lead to additional rounds of showers and thunderstorms
developing over the local waters throughout the day. Additionally,
MLLW at Galveston Bay entrance on Friday evening is expected to
reach between 3.5 and 3.9 feet during high tide, which may cause
some minor coastal flooding.

Rain chances decrease Saturday but increase Sunday with the return
of onshore flow and low level moisture. Another cold front should
arrive Monday. Winds become northerly and increase in the wake for
the front, likely reaching scec/Small Craft Advisory conditions Monday through
Tuesday morning. 24

&&

Preliminary point temps/pops...

College Station (cll) 54 75 54 82 65 / 0 0 0 10 10
Houston (iah) 57 74 57 80 67 / 0 0 0 20 10
Galveston (gls) 64 72 67 82 74 / 0 10 10 30 20

&&

Hgx watches/warnings/advisories...

Texas...none.
GM...small craft should exercise caution until 3 am CDT Thursday for
the following zones: Galveston Bay...Matagorda Bay.

Small Craft Advisory until 3 am CDT Thursday for the following
zones: coastal waters from Freeport to Matagorda Ship
Channel Texas out 20 nm...coastal waters from High Island to
Freeport Texas out 20 nm...waters from Freeport to Matagorda
Ship Channel Texas from 20 to 60 nm...waters from High Island
to Freeport Texas from 20 to 60 nm.

Small craft should exercise caution from 3 am CDT Thursday
through Thursday morning for the following zones: coastal
waters from Freeport to Matagorda Ship Channel Texas out 20
nm...coastal waters from High Island to Freeport Texas out 20
nm.

Small craft should exercise caution from 3 am CDT Thursday
through Thursday afternoon for the following zones: waters
from Freeport to Matagorda Ship Channel Texas from 20 to 60
nm...waters from High Island to Freeport Texas from 20 to 60
nm.



&&

$$

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