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Area forecast discussion
National Weather Service Houston/Galveston Texas
952 am CDT Tue Sep 17 2019


..Flash Flood Watch in effect from 1 PM CDT this afternoon
through Wednesday afternoon...

Showers and isolated thunderstorms are continuing to fill in
across the coastal counties and Gulf waters this morning,
associated with an upper level disturbance moving very slowly to
the northwest across the northwestern corner of the Gulf of
Mexico. The southern portion of Harris County and northern extent
of Galveston County have already seen 1.5 to nearly 3 inches of
rain over the past 12 hours. We have also seen observed rain
rates close to 1.5 inches per hour associated with stronger
storms. Heavy rainfall remains possible through the remainder of
the day, with the best chance south of a line from Columbus to
Conroe to Liberty. Precipitable water values are expected to
increase late this afternoon and through the overnight period as
the upper level low continues to advect in deep tropical moisture.
The track of this disturbance is going to be critical in both the
placement and amount of rainfall. Keep up with the forecast as
minor details are continuing to evolve with the latest model

We are continuing to message the following flood safety tips:
- "turn around, don't drown." Isolated underpasses or low-water
crossings may be life threatening
- monitor the NWS, your local media, hcfcd and other official
weather information sources.



Previous discussion /issued 651 am CDT Tue Sep 17 2019/...

a weak disturbance over the western Gulf coupled with precipitable water values
near 2.55 inches and an upper level low will produce periods of
showers and thunderstorms. Rain will be heavy at times, especially
near the Houston terminals and taf sites near the coast. Ceilings
will bounce around today but MVFR-VFR should be the most common
ceiling category once the morning IFR deck lifts. As the
disturbance approaches the area this evening, ceilings will again
lower and widespread shra/tsra are expected. 43


Preliminary point temps/pops...

College Station (cll) 92 73 89 73 86 / 60 60 70 60 80
Houston (iah) 88 76 85 75 84 / 90 80 90 80 90
Galveston (gls) 86 78 84 80 87 / 100 90 90 80 80


Hgx watches/warnings/advisories...

Texas...Flash Flood Watch from 1 PM CDT this afternoon through Wednesday
afternoon for the following zones: Brazoria
islands...Chambers...coastal Brazoria...coastal
Galveston...coastal Harris...coastal Matagorda...Fort
Bend...Galveston Island and Bolivar Peninsula...inland
Brazoria...inland Galveston...inland Harris...inland
Matagorda...Matagorda islands...northern Liberty...southern

GM...small craft should exercise caution until 7 PM CDT this evening
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...Galveston
Bay...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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