Scientific Forecaster Discussion
fxus64 khgx 190448
Area forecast discussion
National Weather Service Houston/Galveston Texas
1148 PM CDT Wed Sep 18 2019
Previous discussion... /issued 1044 PM CDT Wed Sep 18 2019/
radar imagery shows the placement of a lingering boundary
currently stretch across northern Harris and southern Montgomery
into Liberty and Chambers this evening. The redevelopment along
this axis has only just fired back up over the past half hour. A
Flash Flood Warning remains in effect for Chambers and Liberty
counties this evening, where these stronger storms are continuing
to have rain rates of one to one and a half inches per hour. None
of the latest short term guidance has hinted at the redevelopment
along this boundary until the morning hours, so not anticipating
the development that we are currently seeing to be long lasting.
Cloud tops are also continuing to warm as indicated by water vapor
Have adjusted the short term forecast to show a brief break in
precipitation across most of the region through the overnight
hours before redeveloping across our northeastern zones in the
morning hours. Redevelopment looks possible along a boundary which
should set up across Polk to Walker counties by early morning and
then shift southward across portions of Grimes to Harris and into
Liberty counties by mid-morning. Rainfall totals between 5 to 10
inches remain possible associated with these bands of
precipitation expected to develop, with isolated higher totals.
Confidence remains low in terms of what these potentially higher
total rainfall amounts could be. We will need to keep a close eye
on just how this boundary sets up through the morning hours and
the timing of redevelopment. Expect quick forecast changes as
details continue to evolve through the overnight hours.
for the 19/06z tafs...looking for increasing rain showers/thunderstorms and rain coverage
overnight up north with activity gradually building/working its
way to the S and SW during the day tomorrow. Have lots of vcsh/
thunderstorms in the vicinity to cover this possibility with very low confidence in the
timing and location forecast. 42
Preliminary point temps/pops...
College Station (cll) 74 89 74 90 73 / 60 70 50 50 10
Houston (iah) 77 85 77 87 76 / 100 90 40 50 10
Galveston (gls) 81 85 81 87 81 / 50 90 30 50 10
Texas...Flash Flood Watch until 7 am CDT Thursday for the following
zones: Brazoria islands...Chambers...coastal Brazoria...
coastal Galveston...coastal Harris...Fort Bend...Galveston
Island and Bolivar Peninsula...inland Brazoria...inland
Galveston...inland Harris...Montgomery...northern Liberty...
Polk...San Jacinto...southern Liberty...Trinity...Walker.
GM...small craft should exercise caution until 7 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.