Flash Flood Warning 48, NWS Houston/Galveston, TX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
502 AM CDT Thu Sep 19 2019

.DISCUSSION...
Persistent band of storms initiating over parts of Montgomery
county extending through Liberty and parts of northeastern
Chambers county toward Beaumont have been producing extremely
heavy rainfall with rainfall rates of 3-5"/hour amounts. VWP
clearly showing the deep rich moisture transport into the cell
development...25-49 knots of inflow! Dewpoints of 80 at Galveston
and PW estimates 2.2-2.4" feeding these storms.

Flash flood emergency in effect in
Liberty/Chambers/Jefferson/Orange counties already this morning
and given the rates and previous rainfall these will likely be
extended and may need to be expanded. Rainfall totals in
Liberty/Chambers county this morning over the last 3 days is 6-10"
with some of the hardest hit areas having gotten more than 25"!

Have expanded the Flash flood watch to the west-northwest with the
expectation that storms should initiate and expand west and
northwest from the current storms possibly clipping the northern
portions of Harris. The HRRR of late has been doing a good job
with the pattern though perhaps slightly shifted in location. Then
expecting the storms to expand further both south and north
through mid day well into the Metro. Rainfall rates may start to
come down at least a bit this afternoon as inflow relaxes
somewhat.

Overnight storm threat shifting north tonight and may be focused
more in the College Station to Groveton corridor but mesoscale
features could and may well mess with that expectation. Tonight
the moisture transport relaxes as well...the one concern at this
point will likely be the slow storm motion.

Rain chances tapering down for a few days over the weekend but
then next big surge of moisture arrives Monday and some
indications of weak coastal troughing. Will be keeping an eye on a
wave coming in from the Caribbean Monday and Tuesday probably
arriving in the central Gulf Tuesday/Wednesday. We certainly
wouldn't need this on the heels of Imelda.

45

&&

.MARINE...
An area of low pressure over E TX will move very little today.
The inflow into a nearly stationary line of thunderstorms has
increased and will maintain the SCA for the eastern waters and
Galveston Bay through 15z. This may need to be extended depending
on where/if the line of storms moves. A SCEC will also remain in
effect over the western waters today. A moderate onshore flow will
persist through early Sunday before the pressure gradient finally
begins to relax by Sunday afternoon. A light onshore flow and
lower seas are expected for the first half of next week.

Tide levels are continuing to run about 1.5 to 2.0 feet above
normal. At Galveston Bay Entrance, tide levels are still forecast to
peak between 3.0 to 3.4 feet above MLLW during high tide. Tide
levels will remain elevated through Sunday and water levels could
possibly reach 3.5 feet. A Coastal Flood Advisory may be required
over the weekend. The strong onshore flow will also increase the
risk for strong rip currents along Gulf facing beaches. Due to the
multiple beach hazards in place, will re-issue the Beach Hazards
Statement.
43

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)      91  75  90  74  90 /  90  70  50  10  20
Houston (IAH)              82  77  87  76  89 /  90  50  70  10  30
Galveston (GLS)            82  81  86  81  86 /  60  40  60  10  20

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...Flash Flood Watch through this evening 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 10 AM CDT this morning
     for the following zones: Coastal waters from Freeport to
     Matagorda Ship Channel TX out 20 NM...Matagorda Bay...
     Waters from Freeport to Matagorda Ship Channel TX from 20
     to 60 NM.

     Small Craft Advisory until 10 AM CDT this morning for the
     following zones: Coastal waters from High Island to
     Freeport TX out 20 NM...Galveston Bay...Waters from High
     Island to Freeport TX from 20 to 60 NM.

&&

Discussion...45
Aviation/Marine...43

Hazardous Weather Outlook
National Weather Service Houston/Galveston TX
543 AM CDT Wed Sep 18 2019

TXZ163-176-195>198-210>212-235-335-191045-
Austin-Brazos-Burleson-Coastal Jackson-Colorado-Grimes-Houston-
Inland Jackson-Madison-Waller-Washington-
543 AM CDT Wed Sep 18 2019

This hazardous weather outlook is for portions of Southeast Texas..

.DAY ONE...Today and Tonight
Brief heavy rain may be possible through this evening.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday
Brief heavy rain may develop Thursday into Thursday night shifting
north with time. Otherwise no hazardous weather is expected at
this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed.

TXZ164-177>179-199-200-213-226-227-236>238-300-313-336>338-436-
437-191045-
Brazoria Islands-Coastal Brazoria-Coastal Galveston-
Coastal Harris-Coastal Matagorda-Fort Bend-Inland Brazoria-
Inland Galveston-Inland Harris-Inland Matagorda-Matagorda Islands-
Montgomery-Northern Liberty-Polk-San Jacinto-Southern Liberty-
Trinity-Walker-Wharton-
543 AM CDT Wed Sep 18 2019

This hazardous weather outlook is for portions of Southeast Texas..

.DAY ONE...Today and Tonight
Flash flood watch in effect. Strong thunderstorms with heavy
downpours are likely today through tonight. Rainfall rates of 2 to
4 inches per hour will accompany the storms and flooding will be
possible after yesterday's storms got the ground wet or saturated
in some areas.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday
The threat of heavy rain will be possible Thursday and possibly
into Friday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed.

GMZ335-TXZ214-438-191045-
Chambers-Galveston Bay-Galveston Island and Bolivar Peninsula-
543 AM CDT Wed Sep 18 2019

This hazardous weather outlook is for portions of Southeast Texas..

.DAY ONE...Today and Tonight
Flash flood watch in effect. Strong thunderstorms with heavy
downpours are likely today through tonight. Rainfall rates of 2 to
4 inches per hour will accompany the storms and flooding will be
possible after yesterday's storms got the ground wet or saturated
in some areas. Strong thunderstorms may be capable of waterspouts
and even brief tornadoes today. Strong gusty winds in excess of 40
knots may accompany some of the strongest storms.

Strong rip currents will continue today. Elevated tide levels
will leading to beach flooding near times of high tide.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday
The threat of heavy rain will be possible Thursday and possibly
into Friday.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed.

GMZ330-350-355-370-375-191045-
Coastal waters from Freeport to Matagorda Ship Channel TX out
20 NM-Coastal waters from High Island to Freeport TX out 20 NM-
Matagorda Bay-
Waters from Freeport to Matagorda Ship Channel TX from 20 to
60 NM-Waters from High Island to Freeport TX from 20 to 60 NM-
543 AM CDT Wed Sep 18 2019

This hazardous weather outlook is for portions of Southeast Texas..

.DAY ONE...Today and Tonight
Elevated tides and currents will prevail. Waterspouts will be
possible this morning throughout the afternoon in the stronger
storms that will be focused over the area.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday
Elevated tide levels and stronger currents can be expected through
Friday.

.SPOTTER INFORMATION STATEMENT...

Marine spotter activation may be needed.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
342 AM CDT THU SEP 19 2019

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0245 AM     FLASH FLOOD      1 NNW WINNIE            29.83N 94.39W
09/19/2019                   CHAMBERS           TX   EMERGENCY MNGR

            I 10 FRONTAGE RD AT HWY 124 WAS REPORTED
            CLOSED AND UNSAFE TO TRAVEL.

&&

JPF

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
343 AM CDT THU SEP 19 2019

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0245 AM     FLASH FLOOD      6 W STOWELL             29.79N 94.49W
09/19/2019                   CHAMBERS           TX   EMERGENCY MNGR

            ROADS NORTH AND EAST OF FM 1410 AND FM 1941
            AREA CLOSED AND ARE UNSAFE TO TRAVEL ON.

&&

JPF

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
346 AM CDT THU SEP 19 2019

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0242 AM     FLASH FLOOD      WINNIE                  29.82N 94.38W
09/19/2019                   CHAMBERS           TX   EMERGENCY MNGR

            RICELAND HOSPITAL WAS EVACUATED DUE TO
            FLOODING.

&&

JPF

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
356 AM CDT THU SEP 19 2019

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0353 AM     FLASH FLOOD      LIBERTY                 30.07N 94.78W
09/19/2019                   LIBERTY            TX   LAW ENFORCEMENT

            MULTIPLE ROAD ACROSS LIBERTY COUNTY ARE
            IMPASSABLE. THESE INCLUDE, BUT NOT LIMITED
            TO FM 1010, FM 1008 AT COUNTY ROAD 2313, FM
            1008 AT COUNTY ROAD 2285, AND COUNTY ROAD
            379.

&&

JPF