Flash Flood Warning 47, NWS Houston/Galveston, TX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
644 AM CDT Fri May 31 2024

...New AVIATION...

.SHORT TERM...
(Today through Saturday Night)
Issued at 142 AM CDT Fri May 31 2024

The active weather will continue through Saturday with multiple
rounds of strong to severe storms possible thanks to numerous
shortwaves passing through the zonal flow aloft. The first round
is already on our door step, expected to move into the Piney
Woods/Brazos Valley area by 2 to 4am. The severe potential is not
high with these storms as the area has been worked over pretty
well from last evening's thunderstorms. But, we could still see
some wind gusts to around 30 to 40mph and small hail possible. The
next MCS is located a bit further west, about halfway between
Abilene and Waco as of 2am, and the trajectory of this line is
currently bringing it down along the Brazos River through SE Texas
closer to daybreak. Now this area hasn't seen the same number of
storms that the rest of the region experienced yesterday, so the
potential for strong to severe thunderstorms is higher with this
MCS than the storms moving through the Pineywoods this morning.
Guidance is also indicating that another MCS may move through the
region this afternoon with additional showers and storms
developing overnight tonight into Saturday. But, confidence on the
where, when, and strength of these additional storms is unusually
low at this time. This uncertainty is due to figuring out the the
exact timing and location of the passing shortwaves, how much the
atmosphere can recharge between rounds, and mesoscale features
(boundary interactions) that is impossible to accurately predict
this far out. All-in-all a very messy forecast.

SPC maintains a Slight Risk (level 2 of 5) for most of SE Texas
today due to the MCS potential. Damaging winds will be the main
concern, but hail and a brief tornado cannot be ruled out. There
is also a Marginal Risk (level 1 of 5) for Saturday, again with
strong winds being the primary threat. There is also the potential
for locally heavy rainfall this morning through this afternoon
with the MCSs passing through. These storms will be fairly
progressive, but could produce rainfall rates of 1-3" per hour or
higher. Minor urban and small stream flooding would be the primary
concern, but cannot out rule some areas experiencing flash
flooding. WPC has placed most of SE Texas in a Slight Risk (level
2 of 4) for Excessive Rainfall today, and then most areas north of
I-10 in a Marginal Risk (level 1 of 4) on Saturday.

Temperature forecast for this afternoon is also tricky due to the
uncertainty of the storms timing/locations. Expecting afternoon
high temperatures to be in the mid to upper 80s, but could see
some spots reach the low 90s if enough sunshine can peak through.
Overnight low temperatures will continue to be on the unseasonably
warm side, especially along the coast, with overnight minimum
temperatures in the mid to upper 70s inland and low 80s along the
immediate coast. High temperatures tomorrow should rise into the
upper 80s to low 90s for most of the area as precipitation
coverage should be less.

Fowler

&&

.LONG TERM...
(Sunday through Thursday)
Issued at 142 AM CDT Fri May 31 2024

We will continue to have additional rounds of showers and
thunderstorms through early next week as a few more upper level
disturbances embedded in the quasi-zonal flow aloft move across
Southeast Texas. We may also continue to see several storms from
Central and North Texas pushing into our region from time to time.

On Sunday, we could be seeing isolated to scattered showers and
isolated thunderstorms as a short wave passes through Texas and
combines with sufficient low moisture, instability along with vort
maxes pushing across the our area and possibly a low level jet.
On Monday, although conditions look good for the development of
storms, it seems we may stay capped enough to limit activity. A
similar pattern could occur on Tuesday, although it does seem a
little more favorable for rain in the afternoon and early evening
hours.

There is some model inconsistency on Wednesday, but global models
are hinting at the passage of an upper level trough moving across
the Southern Plains which could try to push a weak cold front
close to Southeast Texas, and if it does move into our local area,
it could stall over us. There is a chance the boundary meanders
over us on Thursday and may help the development of some isolated
showers and thunderstorms in the afternoon as the upper level
trough moves across the eastern Texas region.

Unfortunately, the models have been performing very poorly with
the current weather trend, especially with timing. Thus, the
forecast may undergo a few modifications during the next few days
given that it has been a bit tricky to pin point the time of the
day or night and exact location of some of these storms.

With respect to temperatures, we will see highs in the upper 80s
to low 90s on Sunday and then gradually warn through mid week
where we will have highs in the low to mid 90s. The lows will be
generally in the mid to upper 70s, a little cooler in some spots
along the Brazos Valley and Piney Woods region.

24

&&

.AVIATION...
(12Z TAF Issuance)
Issued at 629 AM CDT Fri May 31 2024

A line to strong to severe thunderstorms is moving through the
area this morning. Has already passed through CLL and UTS, will be
passing through IAH and CXO shortly, and then down through the
coastal terminals through the mid morning. Expect heavy rainfall,
gusty winds to 30-40kt, and low CIGs down to around 1000ft as the
line moves through. Popup thunderstorms will precede the line of
storms, and then expected SHRA for a couple of hours after the
line moves through. There will be a lull in the showers and
thunderstorm activity, but may again see some showers and isolated
thunderstorms this afternoon. VFR conditions will generally
prevail through the day today, then MVFR conditions are expected
tonight into Saturday morning as CIGS lower to 1500-2500ft with
patchy fog possible. Additional showers and storms will be
possible Saturday morning and afternoon.

Fowler

&&

.MARINE...
Issued at 142 AM CDT Fri May 31 2024

Light to moderate onshore winds and seas of 4 to 6 feet can be
expected through the next few days and may become moderate to
strong briefly at times. Caution flags may be needed from time to
time. Periods of showers and storms are expected today into this
weekend. Some storms could be strong to severe, capable of
producing strong gusty winds and higher seas. There is a chance
for strong rip currents along the Gulf facing beaches during the
next couple of days. Beachgoers should exercise caution in the
waters and follow beach flags and lifeguard guidance.

24

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)	  86  73  88  75 /  80  30  50  10
Houston (IAH)			  87  76  88  76 /  70  40  60  10
Galveston (GLS)			  86  80  86  80 /  50  40  40  20

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...Small Craft Advisory until 10 AM CDT this morning for GMZ330-335-
     350-355.

     Small Craft Should Exercise Caution from 10 AM CDT this morning
     through this evening for GMZ330-335-350-355.

     Small Craft Should Exercise Caution through this evening for
     GMZ370-375.

&&

SHORT TERM...Fowler
LONG TERM....Cotto (24)
AVIATION...Fowler
MARINE...Cotto (24)

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>