Flash Flood Warning 2, NWS Houston/Galveston, TX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
230 PM CDT Mon May 5 2025

...New LONG TERM, MARINE...

.SYNOPSIS...
Issued at 1224 PM CDT Mon May 5 2025

An active weather pattern is expected to bring a daily risk of
scattered showers and thunderstorms today, tomorrow, and
Wednesday. Locally heavy rainfall capable of localized flooding is
a concern. In addition, a few strong to severe thunderstorms are
likely. The highest risk of strong to severe storms will be over
our northern counties on Tuesday. However, most of our country
warning area is at risk of experiencing strong thunderstorms each
day. Hail and damaging wind gusts are the primary concern. A few
thunderstorms may be capable of producing a tornado, especially on
Tuesday in our northern counties.

&&

.SHORT TERM...
(Today through Wednesday) Issued at 1224 PM CDT Mon May 5 2025

TODAY:

Mid/upper disturbances in the diffluent flow aloft will interact
with an increasingly moisture rich atmosphere today, resulting in
scattered showers and thunderstorms. A few heavier/stronger
thunderstorms are expected. Locally heavy rainfall, frequent
lightning, and damaging wind gusts are the primary concern.
However, the environment is also favorable for a few thunderstorms
to produce large hail. Gusty east-southeast winds are expected to
continue this afternoon with highs reaching the low 80s. Areas
that experience showers/storms earlier in the afternoon may remain
in the 70s.

TONIGHT:

Lingering thunderstorms possible in the evening. Widely scattered
showers are possible overnight. Inland winds are expected to
become less gusty. Windier conditions expected near the coast.
Conditions will be muggy with lows ranging from the mid 60s in
our northern counties to low 70s at the coast.

TUESDAY:

The vertical wind profile will become highly sheared over
southeast Texas while the presence of a mid/upper low over New
Mexico will help to enhance large scale diffluence and lift aloft.
At the surface, a warm front pushes northward over our area,
enhancing LL convergence and further supporting lift. This will
likely lead to another round of scattered thunderstorms.
Parameters appear to most favor our northern counties for more
widespread thunderstorm activity late Tuesday morning into the
afternoon. Large hail and damaging wind gusts are the primary
concerns. But given the low-level shear profile, we cannot rule
out thunderstorms capable of producing a tornado. Thunderstorms
are likely to result in locally heavier rainfall, possibly up to
4-6 inches in some spots. Thus, a Flood Watch has been issued for
our northern counties for Tuesday.

Worth mentioning that strong thunderstorms will also be possible
across our central and southern counties, even though the threat
is highest across our northern counties.

TUESDAY NIGHT - WEDNESDAY:

The thunderstorm threat is expected to shift southward during this
time frame. Though the environment appears to become somewhat less
favorable for severe weather, we still think locally heavy/strong
thunderstorms are possible Tuesday night into Wednesday. The
environment may become more favorable for thunderstorms training
over the same area. Therefore, we will need to monitor the
potential for localized flash flooding across our southern /
coastal counties.

Current guidance suggest most of the thunderstorms will be
offshore by Wednesday afternoon. But uncertainties remain higher
than normal regarding the timing the exact timing of thunderstorms
Tuesday night into Wednesday.

Self

&&

.LONG TERM...
(Wednesday through next Sunday)
Issued at 229 PM CDT Mon May 5 2025

Rain and storm chances continue on Thursday, though it will be on
the downward trend. The cold front is progged to be along the coast
or over the Gulf waters by Thursday morning. However, showers and
thunderstorms will be ongoing early Thursday as an inverted surface
trough (surface convergence) moves through the region. Deterministic
solutions, including NAM, bring highest rainfall totals of up to an
1-inch along the coast. A few weak shortwaves embedded in the flow
aloft will move through on Friday. Despite limited low-level
moisture, we cannot ruled out a few showers, especially in the
afternoon with the peak daytime heating. Surface high pressure
builds in during the weekend, resulting in a drier forecast. Return
flow from the departing high is expected on Monday. This will bring
near seasonal temperatures for the upcoming week.

JM

&&

.AVIATION...
(18Z TAF Issuance)
Issued at 1224 PM CDT Mon May 5 2025

Gusty ESE winds and scattered SHRA/TSRA expected this afternoon.
Winds in the vicinity of any TSRA could exceed 30 knots and become
directionally variable. Risk of TSRA decreases overnight while
flight conditions generally trend MVFR. Areas of IFR possible.
Overnight winds become less gusty, though remain elevated near the
coast. Stronger SE winds expected tomorrow, along with another
chance of scattered SHRA/TSRA. A few stronger thunderstorms
capable of hail are possible.

Self

&&

.MARINE...
Issued at 229 PM CDT Mon May 5 2025

Gusty east-southeast winds, building seas, and scattered showers
and a few thunderstorms are expected today. Non-thunderstorms
winds are expected to gust up to around 30 knots. Winds in the
vicinity of a thunderstorm could gust over 40 knots. Could not
rule out isolated severe thunderstorms capable of localized gusts
up to 50 knots. Gusty southeast winds and shower/thunderstorm
chances continue into Tuesday. By Tuesday night into Wednesday,
non-thunderstorm related winds are expected to decrease. However,
the presence of continued thunderstorm activity means that winds
could be highly variable both in terms of direction and speed.
Therefore, be advised that thunderstorm associated winds will
remain high even though the official forecasted overall wind
decreases into Wednesday. Beyond Wednesday, the forecast becomes
less eventful as winds and seas gradually become less hazardous.
By Thursday, winds are expected to shift to a more northerly
regime and remain that way into the weekend.

Self

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)	  66  81  67  84 /  80 100  40  40
Houston (IAH)			  68  82  70  83 /  80  90  80  70
Galveston (GLS)			  74  82  73  80 /  70  60  80  80

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...Flood Watch from Tuesday morning through late Tuesday night for
     TXZ163-164-176>179-196-198.

GM...Small Craft Advisory until 7 PM CDT Tuesday for GMZ330-335-350-
     355-370-375.

&&

SHORT TERM...Self
LONG TERM....JM
AVIATION...Self
MARINE...Self

Preliminary Local Storm Report
National Weather Service Houston/Galveston TX
435 PM CDT Mon May 5 2025

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

0430 PM     Hail             6 NNW West Columbia     29.22N 95.69W
05/05/2025  E1.00 Inch       Brazoria           TX   Fire Dept/Rescue

            Fire Department reported quarter size hail
            at HWY 35 and CR 5.

&&

HA

Special Weather Statement
National Weather Service Houston/Galveston TX
455 PM CDT Mon May 5 2025

TXZ197-211>213-052215-
Washington TX-Waller TX-Inland Harris TX-Austin TX-
455 PM CDT Mon May 5 2025

...A STRONG THUNDERSTORM WILL IMPACT NORTHEASTERN AUSTIN...
SOUTHEASTERN WASHINGTON...NORTHWESTERN WALLER AND WESTERN HARRIS
COUNTIES THROUGH 515 PM CDT...

At 454 PM CDT, Doppler radar was tracking a strong thunderstorm over
Hempstead, moving east at 30 mph.

HAZARD...Wind gusts up to 50 mph and nickel size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

Locations impacted include...
Hempstead, Prairie View, Waller, and Pine Island.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

A Severe Thunderstorm Watch remains in effect until 800 PM CDT for
southeastern Texas.

&&

LAT...LON 3002 9624 3021 9617 3022 9590 2995 9590
TIME...MOT...LOC 2154Z 276DEG 27KT 3010 9612

MAX HAIL SIZE...0.88 IN
MAX WIND GUST...50 MPH

Self

Special Weather Statement
National Weather Service Houston/Galveston TX
512 PM CDT Mon May 5 2025

TXZ212-213-052230-
Waller TX-Inland Harris TX-
512 PM CDT Mon May 5 2025

...A STRONG THUNDERSTORM WILL IMPACT NORTHERN WALLER AND NORTHWESTERN
HARRIS COUNTIES THROUGH 530 PM CDT...

At 512 PM CDT, Doppler radar was tracking a strong thunderstorm over
Prairie View, moving east at 30 mph.

HAZARD...Wind gusts up to 50 mph and nickel size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

Locations impacted include...
Hempstead, Prairie View, Hockley, Waller, and Pine Island.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

A Severe Thunderstorm Watch remains in effect until 800 PM CDT for
southeastern Texas.

&&

LAT...LON 3001 9608 3007 9611 3019 9605 3017 9581
      2998 9580
TIME...MOT...LOC 2212Z 275DEG 27KT 3010 9602

MAX HAIL SIZE...0.88 IN
MAX WIND GUST...50 MPH

Self

Special Weather Statement
National Weather Service Houston/Galveston TX
522 PM CDT Mon May 5 2025

TXZ177-199-052245-
Walker TX-Montgomery TX-
522 PM CDT Mon May 5 2025

...A STRONG THUNDERSTORM WILL IMPACT NORTHWESTERN MONTGOMERY AND
SOUTH CENTRAL WALKER COUNTIES THROUGH 545 PM CDT...

At 521 PM CDT, Doppler radar was tracking a strong thunderstorm 8
miles southwest of Huntsville State Park, or 11 miles northwest of
Willis, moving east at 35 mph.

HAZARD...Wind gusts up to 50 mph and penny size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

This storm will remain over mainly rural areas of northwestern
Montgomery and south central Walker Counties.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

A Severe Thunderstorm Watch remains in effect until 800 PM CDT for
southeastern Texas.

&&

LAT...LON 3045 9571 3059 9575 3065 9555 3050 9550
TIME...MOT...LOC 2221Z 255DEG 30KT 3053 9563

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...50 MPH

Self

Special Weather Statement
National Weather Service Houston/Galveston TX
537 PM CDT Mon May 5 2025

TXZ200-213-214-300-313-052315-
Northern Liberty TX-Chambers TX-Coastal Harris TX-
Southern Liberty TX-Inland Harris TX-
537 PM CDT Mon May 5 2025

...A STRONG THUNDERSTORM WILL IMPACT NORTHWESTERN CHAMBERS...
SOUTHWESTERN LIBERTY AND NORTHEASTERN HARRIS COUNTIES THROUGH 615 PM
CDT...

At 537 PM CDT, Doppler radar was tracking a strong thunderstorm over
Highlands, moving northeast at 45 mph.

HAZARD...Pea size hail.

SOURCE...Radar indicated.

IMPACT...Minor hail damage to vegetation is possible.

Locations impacted include...
Northwestern Pasadena, northwestern Baytown, Deer Park, Liberty,
Dayton, Cloverleaf, Highlands, Channelview, Barrett, Kingwood,
Crosby, northwestern Mont Belvieu, Ames, Kenefick, Lake Houston Dam,
Lake Houston, Houston Ship Channel, San Jacinto State Park, Sheldon,
and Northshore.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

A Severe Thunderstorm Watch remains in effect until 800 PM CDT for
southeastern Texas.

&&

LAT...LON 2968 9512 2974 9521 3015 9511 3006 9465
TIME...MOT...LOC 2237Z 218DEG 38KT 2983 9507

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...<30 MPH

Adams

Preliminary Local Storm Report
National Weather Service Houston/Galveston TX
546 PM CDT Mon May 5 2025

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

0502 PM     Hail             3 ENE Fresno            29.56N 95.41W
05/05/2025  E1.00 Inch       Brazoria           TX   Public

            Relative of NWS Employee reports quarter
            size hail.

&&

HA