Scientific Forecaster Discussion
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Area forecast discussion
National Weather Service Houston/Galveston Texas
1156 PM CDT Thu Oct 17 2019
Aviation [06z taf issuance]...
VFR and light winds throughout. Some MVFR level clouds linger at
gls, and radar indicates some returns on radar, but will gamble
for the time being on rain not reaching the ground. Even if it
does, impacts will be nil.
Still beyond the scope of this forecast cycle, but will soon have
to more seriously evaluate the quality of moisture return as winds
become more onshore towards Saturday night, and its impact on
potential for patchy fog at the usual suspects.
Previous discussion /issued 619 PM CDT Thu Oct 17 2019/...
Short term [this afternoon through friday]...
a compact, yet potent upper level low over south-central Texas is
producing some patchy light rain over parts of south-central and
the middle Texas coast. The upper level feature will move east
toward Matagorda Bay and into the Gulf between 06-12z and any
residual light rain near the coast will end. Weak upper level
ridging will amplify over south Texas on Friday in the wake of the
upper level feature. Fcst soundings show a dry air mass in place
so skies are expected to be mostly sunny. 850 mb temps would
support high temperatures in the lower 80's. The upper level ridge
gets nudged eastward Friday night as a weak short wave over the
Southern Plains approaches North Texas. 43
Long term [friday night through thursday]...
a warming trend will continue through the weekend, with increasing
cloud cover. Scattered showers will be possible north of I-10 late
Saturday into early Sunday as a short wave trough coupled with
favorable jet dynamics could produce some rain mostly during the
afternoon hours. Pops will be on the rise through the weekend
ahead of a cold front that will move through the region Monday.
This cold front looks to be rather strong in nature, and should
push through the Gulf waters by the afternoon hours Monday.
Showers and thunderstorms will be possible with this feature,
and the placement of the upper-level jet could result in the
potential for some strong to severe storms across our northern
zones Monday. We will need to pin down the details in the
mesoscale models and forecast soundings as the event gets closer.
Winds will blow out of the north, increasing to around 15 knots
and gusty inland by early Tuesday morning. Expect at least a Ten
Degree difference between high temperatures Sunday to Tuesday
behind the front. High temperatures should stay in the 70s to 80s
Tuesday through Thursday behind the frontal passage, with low
temperatures bottoming out in the upper 40s to 60s.
small craft should continue to exercise caution through the
evening hours before the pressure gradient slowly relaxes. An
area of disturbed weather, otherwise known as potential tropical
cyclone sixteen, will continue to move to the northeast across the
Gulf of Mexico tomorrow and eventually make landfall along the
coast of the Florida Panhandle Saturday. That said, very minimal
impacts can be anticipated for the Upper Texas coast, with the
chance for slightly elevated tide levels and seas up to 3 to 5
feet at times this weekend. A cold front should push through the
Gulf waters Monday afternoon and into the evening hours. Northerly
winds of at least scec conditions, approaching Small Craft Advisory criteria will
be possible behind the frontal passage.
Preliminary point temps/pops...
College Station (cll) 52 81 61 88 63 / 0 0 0 0 10
Houston (iah) 57 80 63 87 68 / 0 0 0 10 10
Galveston (gls) 64 77 71 86 76 / 50 0 0 10 10
GM...small craft should exercise caution until 5 am CDT Friday 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.