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Area forecast discussion
National Weather Service Houston/Galveston Texas
1148 PM CDT Thu Sep 19 2019

Aviation...
expecting lowering ceilings overnight, and maybe some fog too
(mainly mvfr). Could see some rain showers/thunderstorms and rain development before
sunrise, and expect better chances of rain showers/thunderstorms and rain coming during
the daytime hours. Anything that does develop should weaken/
dissipate in the evening. 42
&&

Previous discussion... /issued 1123 PM CDT Thu Sep 19 2019/

Update...
not much to add this late. Flood Watch remains in effect through
12z tomorrow morning and, due to very slow drainage, we may need
to extend the two areal flood warnings that are currently in
effect.

Early Friday morning looks quiet, no appreciable rain through
sunrise. There is a good chance that many that experienced high
rainfall/flooding today will again be dealing with scattered
showers and thunderstorms through tomorrow afternoon. Better
performing, higher resolution modeling all show scattered
convection forming over the southern County Warning Area and traveling northward
through the central and northern counties through the afternoon
hours. Some of these thunderstorm clusters could put down a quick
one to two inches per hour. While tomorrow's rainfall wouldn't
typically produce nothing more than minor nuisance flooding, another
1 to 2 inches over those areas hardest hit by today's rain will
only exacerbate ongoing flooding; slow the fall of current
inundating flood waters. 31

Previous discussion... /issued 744 PM CDT Thu Sep 19 2019/

Aviation...
have been seeing decreasing rain showers/thunderstorms and rain coverage, and expect this trend
to continue overnight with only limited additional development anticipated.
Could see some lower ceilings/visibilities (mainly mvfr). With heating
tomorrow, expecting to see some rain showers/thunderstorms and rain development along with lifting
ceilings that should last until around sunset. Mainly southeast to S winds
tonight and tomorrow, generally peaking around or slightly above 10
knots. 42

Previous discussion... /issued 506 PM CDT Thu Sep 19 2019/

Flood Watch remains in effect for most of southeast Texas overnight...

Short term [tonight through Friday night]...
the overnight mesoscale convective system/band of storms has persisted and has slowly
sagged south this afternoon is still going fairly strong across
areas stretching from Columbus southeast to Jamaica Beach at this
time. Of concern for the next few hrs is the possibility of
another embedded shortwave approaching from the west. Scattered
storms have been developing/filling in from this direction this
afternoon and we are still seeing decent inflow/moisture from the
Gulf. Keeping the Flood Watch in place overnight given all these
ongoing issues with high water/saturated grounds as it should not
take that much for conditions to get bad once again. But despite
this being said, will be expecting the activity to decrease a
shortly/this evening with the loss of heating. However...given
this very very tropical air mass over southeast Texas and the remnants of
Imelda still lingering in and near East Texas...this break could be
brief. Would not be at all surprised with spotty shras developing
overnight.

Models are continuing to shift the remnants of this system to the
NE tomorrow, and we will be expecting the focus of development to
also shift more NE/east with time. Barring any leftover outflows (or
other boundaries), activity tomorrow afternoon will be more
scattered in nature. 41/39/24/12/48/42/31

Long term [saturday through thursday]...
with the upper ridge building across the region, a slightly drier
warmer pattern is expected this weekend. However, rain chances to
return by the start of next week as a deep upper trof (digging in
from the west) help to draw another surge of moisture in from the
Gulf. GFS going with the higher precipitable water progs for Mon/tues (2.0-2.2").
But by the middle/end of the week, European model (ecmwf) leaning in with the
higher pws/pops (and perhaps more further south). A bear watch
may be needed for this time frame. 41

Marine...
given the location of the remnants of Imelda...did keep scec flags
in place across the eastern half of the marine zones for the
overnight hours. Otherwise, winds/seas will be decreasing as the
upper ridge builds over the region this weekend. 41

Climate...

Rainfall records set for today:

City of houston: a record rainfall of 9.18 inches was set at city of
Houston today. This breaks the old record of 6.92 inches set in
1979. This is now the wettest day in September, breaking the old
record of 7.73 inches set on September 13 2008 with Hurricane Ike.

Galveston: a record rainfall of 5.70 inches was set at Galveston
today. This breaks the old record of 5.11 inches set in 1979.

&&

Preliminary point temps/pops...
College Station (cll) 73 90 75 92 73 / 50 40 10 20 20
Houston (iah) 76 88 76 91 76 / 50 70 10 30 20
Galveston (gls) 80 87 81 90 80 / 40 40 20 30 20

&&

Hgx watches/warnings/advisories...
Texas...Flash Flood Watch until 7 am CDT Friday for the following zones:
Austin...Brazoria islands...Brazos...Burleson...Chambers...
coastal Brazoria...coastal Galveston...coastal Harris...
Fort Bend...Galveston Island and Bolivar Peninsula...
Grimes...inland Brazoria...inland Galveston...inland
Harris...Montgomery...northern Liberty...Polk...San
Jacinto...southern Liberty...Trinity...Walker...Waller...
Washington.

GM...small craft should exercise caution until 7 am CDT Friday for
the following zones: coastal waters from High Island to
Freeport Texas out 20 nm...Galveston Bay...waters from high

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