Tornado Warning 13, NWS Houston/Galveston, TX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
101 PM CDT Tue May 23 2023

...New AVIATION...

.SHORT TERM...
(Today through Wednesday Night)
Issued at 307 AM CDT Tue May 23 2023

Rapidly weakening showers and thunderstorms working their way out of
north central Texas might edge their way into parts of our northern
counties this morning. Have low rain chances in that area in case
something survives. Did raise Pops for the rest of the area today as
any boundaries from this activity combined with daytime heating
might result in some development, but kept the values just below the
mention of rain as current thinking is that activity will be quite
isolated. We will monitor as the morning/day progresses and adjust
rain chances upward as needed. Similar situation can be expected
late tonight through the day on Wednesday as additional development
in a northwest flow aloft tries to work its way into our area. In
this case, confidence is better that we will see some rain, so have
isolated to scattered showers and thunderstorms in the forecast.
Anything that does develop should dissipate Wednesday evening.

For temperatures, much of the area should see highs today reach the
upper 80s to around 90 (closer to the mid 80s at the beaches), and
lows tonight should bottom out in the mid to upper 60s with some
spots in the Houston area having trouble falling below 70 (closer to
the mid 70s at the beaches). Have similar temperature forecasts for
Wednesday and Wednesday night, but Wednesday's highs might end up a
couple degrees cooler where rains develop.

42

&&

.LONG TERM...
(Thursday through Monday)
Issued at 307 AM CDT Tue May 23 2023

Global models have indicated little change to the extended pattern
with a blocking pattern dominating the CONUS throughout the end of
the week and into the upcoming weekend, bringing SE TX a period of
generally benign and consistent weather. Rainfall from the passage
of Wednesday's midlevel shortwave is generally expected to have
tapered off by early Thursday. However, depending on the exact
timing of the feature along with the potential for any lingering
boundaries associated with dispersed convection from Wednesday, a
stray storm or two cannot fully be ruled out early on Thursday.
Otherwise, with midlevel ridging continuing to dominate the area
through the weekend, the prevailing trend of warm and humid
conditions with limited rainfall chances is expected to continue.

A slight breakdown of the midlevel ridge is expected by late
Saturday/early Sunday, with both the GFS and the EC now indicating
the approach of a very weak surface boundary during this time.
While moisture will remain abundant (total PWs of ~1.5-7) during
this time, forcing will otherwise be relatively weak and thus only
scattered to isolated convection is anticipated with minimal
rainfall totals. Midlevel flow will become increasingly zonal by
Monday/Tuesday, with synoptic models now indicating the approach
of a more potent midlevel shortwave. This should be sufficient
enough to trigger some scattered thunderstorm activity, and as a
result have included 20-30% PoP in this forecast package.

Overall, temperature forecast has remained generally on track and
consistent from previous issuances with daytime highs in the upper
80s to lower 90s and overnight lows in the upper 60s to 70s. Given
relatively weak WAA and thus slightly lower surface dew points,
maximum heat index values do not look to exceed 95.

Cady

&&

.AVIATION...
(18Z TAF Issuance)
Issued at 1229 PM CDT Tue May 23 2023

Light winds and VFR conditions should prevail throughout the day.
Isolated showers and storms may develop along the sea breeze this
afternoon, remaining mainly isolated to areas south of I-10. Winds
become calm and variable overnight, allowing for another round of
patchy fog to develop across portions of SE Texas. Fog development
may be hindered by the next storm system, which should approach
SE Texas early Wednesday morning. Current guidance suggests storms
developing near KCLL around this time with rain chances rising
and becoming more widespread into Wednesday afternoon. Any fog
should burn off after sunrise, with VFR conditions prevailing
through the day on Wednesday.

03

&&

.MARINE...
Issued at 307 AM CDT Tue May 23 2023

Light winds and low seas will continue to prevail throughout the
remainder of the week and into the weekend, with neither seas nor
wind speeds expected to approach caution thresholds over the next
seven days. Scattered showers and storms are possible on Wednesday
as a disturbance moves through the area, but strong storms are not
expected to occur.

Cady

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)	  68  86  67  86 /  20  20  10  10
Houston (IAH)			  68  89  69  88 /  10  30  10  10
Galveston (GLS)			  75  86  75  84 /  20  20  10  10

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&

SHORT TERM...42
LONG TERM....Cady
AVIATION...03
MARINE...Cady

Special Weather Statement
National Weather Service Houston/Galveston TX
210 PM CDT Tue May 23 2023

TXZ176-177-198-231945-
Madison TX-Walker TX-Grimes TX-
210 PM CDT Tue May 23 2023

...A strong thunderstorm will impact portions of northeastern Grimes,
southeastern Madison and west central Walker Counties through 245 PM
CDT...

At 210 PM CDT, Doppler radar was tracking a strong thunderstorm near
Madisonville, moving southeast at 30 mph.

HAZARD...Winds in excess of 30 mph and penny size hail.

SOURCE...Radar indicated.

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

Locations impacted include...
Northwestern Huntsville and Crabbs Prairie.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 3090 9597 3097 9582 3077 9554 3063 9590
TIME...MOT...LOC 1910Z 330DEG 25KT 3088 9584

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...30 MPH

Special Weather Statement
National Weather Service Houston/Galveston TX
244 PM CDT Tue May 23 2023

TXZ177-178-232015-
San Jacinto TX-Walker TX-
244 PM CDT Tue May 23 2023

...A strong thunderstorm will impact portions of northwestern San
Jacinto and southeastern Walker Counties through 315 PM CDT...

At 243 PM CDT, Doppler radar was tracking a strong thunderstorm over
northwestern Huntsville, moving southeast at 25 mph.

HAZARD...Wind gusts up to 50 mph and half inch hail.

SOURCE...Radar indicated.

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

Locations impacted include...
Huntsville, Huntsville State Park and Crabbs Prairie.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 3071 9574 3084 9551 3062 9533 3051 9560
TIME...MOT...LOC 1943Z 330DEG 24KT 3073 9558

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...50 MPH