901
FXUS64 KHGX 200855
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
355 AM CDT Thu Mar 20 2025

...New SHORT TERM, LONG TERM, MARINE, FIRE WEATHER...

.SHORT TERM...
(Today through Friday Night)
Issued at 344 AM CDT Thu Mar 20 2025

High pressure will settle into Southeast Texas today. Winds will be
out of the north today at around 10-15 mph with gusts to around 25
mph during the afternoon hours. These northerly winds will continue
to supply much drier air to the area, resulting in RH percentages
dropping into the teens to low 20s again this afternoon. As a
result, have opted to issue another Red Flag Warning for today for
Inland Southeast Texas (Barrier Islands are excluded). This will be
in effect from 1 PM this afternoon through 7 PM this evening.

The positive part about the northerly winds is that they are also
drawing in cooler air, which will keep high temperatures on the
cooler side today. Expect highs in the 60s to around 70 degrees
today with mostly sunny to sunny skies.

Onshore flow will return later tonight as the surface high pressure
continues off to the east. In a bit of a rinse and repeat fashion,
this will once again set the stage for a warming trend heading into
the weekend. Highs for Friday will be in the 70s area wide. Lows
Friday night will be in the 50s inland and low 60s on the coast.

Adams

&&

.LONG TERM...
(Saturday through Wednesday)
Issued at 344 AM CDT Thu Mar 20 2025

By Saturday, surface high pressure will be off to the east over the
Northwestern Gulf/Florida with zonal flow in place aloft. Steady
onshore flow in this regime will facilitate WAA/moisture advection
over the weekend with highs progged to reach the 70s to mid 80s and
overnight lows in the 60s. Warm and largely quiet weather to start
the weekend.

Sunday will see a more active weather pattern emerge as a mid/upper
level trough digs into the Northern Plains/Mississippi River Valley.
Moisture advection strengthens as the surface lows associated with
this system deepen, raising PWs to 1.0-1.4 inches. As this system
tracks eastward towards the Great Lakes, it will push a cold front
into the region during the late afternoon/evening on Sunday. With
respect to convective parameters, LREF means show 1250-2000 J/kg
of SFC CAPE and 30-40 knots of Bulk shear in place across the
region ahead of the approaching front. Both of these components
are maximized across the Brazos Valley/Piney Woods area, which
looks to be more at risk of seeing stronger, possibly severe
storms. SRH is on the low side, only around 100-150 m2/s2 in the
lowest 3km preceding the boundary. Narrowing in on forecast
soundings near Crockett/Livingston, we can see dry mid levels,
semi-dry low levels with high LCL heights, which looks less
favorable in terms of tornadic storms. Otherwise, weak capping is
progged to be in place, with LREF mean CIN ranging from -25 to -50
J/KG around/north of the I-10 corridor. With this, Thermal
Expansion Index values near 25, cloud layer shear of 60 knots,
mean MU CAPE upwards 2600 J/KG and mid-level lapse rates over 8
degC/KM still indicate a potent environment for severe weather.

As it currently stands, SPC has areas generally north of a line from
College Station to Livingston under a Slight Risk of Severe Weather
for Sunday. This translates to a 15% chance of severe weather
occuring within 25 miles of any given point. While 15% doesn`t sound
all that high, it is in the context that this outlook is for day 5
of the forecast, which is not often seen unless confidence is high.
With respect to timing, severe storms will be most likely occur
during the afternoon through the evening on Sunday, with storms
tapering off overnight into Monday as the front moves towards the
coast. With respect to the specific hazards, large hail and damaging
wind gusts will be the main severe weather hazards. It`ll be worth
monitoring the forecast these next few days to see how this threat
evolves.

The cold front will push offshore by Monday morning as surface high
pressure fills in across the Southern Plains. North/northeast winds
veer as this surface high slides east, with onshore winds returning
Tuesday afternoon/evening. Low PWs and weak mid-level ridging should
keep benign conditions in place through mid next week with sparse
rain chances. Highs dip down into the 70s on Monday, but should
bounce back into the 80s at most places by Tuesday.

03


&&

.AVIATION...
(00Z TAF Issuance)
Issued at 613 PM CDT Wed Mar 19 2025

VFR conditions, though gusty NW winds will continue into the
overnight hours. Inland areas should begin seeing some temporary
lulls in the gustiness after 9z or so, but we`ll see them begin
gusting to 20-25kt again toward mid morning Thursday as we get
some mixing. 47

&&

.MARINE...
Issued at 344 AM CDT Thu Mar 20 2025

Strong offshore winds of 20 to 30 knots with gusts up to 35 knots
continue early today, but should slowly ease throughout the morning.
These strong winds have brought low water Levels in the bays under
-1.0 ft MLLW and wave heights of 6 to 11 feet over the Gulf waters.
A Low Water Advisory remains in effect across the bays through 10 AM
this morning. A Small Craft Advisory will be in effect for all
waters through 1 PM to allow these winds and seas to diminish. Winds
become light this evening, veering overnight and becoming
southeasterly on Friday. Light to moderate onshore flow continues
into Sunday with showers and storms developing during the afternoon
and overnight as a cold front pushes offshore. East/Northeast flow
develops on Monday behind the front.

03


&&

.FIRE WEATHER...
Issued at 344 AM CDT Thu Mar 20 2025

While winds will not be as strong as the previous few days (10-
15g25mph), fuels are very dry and relative humidity values are very
low (teens into the low 20s. As a result, a Red Flag Warning has
been issued for Southeast Texas today from 1 PM through 7 PM. The
islands are excluded from the warning. Please avoid outdoor
burning, open flames or sparks, and parking in grassy areas.

Adams

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)  68  40  78  53 /   0   0   0   0
Houston (IAH)  69  44  76  57 /   0   0   0   0
Galveston (GLS)  68  58  70  63 /   0   0   0   0

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...Red Flag Warning from 1 PM this afternoon to 7 PM CDT this
     evening for TXZ163-164-176>179-195>200-210>214-226-227-
     235>238-300-313-335>338.

     Wind Advisory until 7 AM CDT this morning for TXZ214-313-335>338.

     Wind Advisory until 10 AM CDT this morning for TXZ436>439.

GM...Low Water Advisory until 10 AM CDT this morning for GMZ330-335.

     Small Craft Advisory until 1 PM CDT this afternoon for GMZ330-
     335.

     Gale Warning until 4 AM CDT early this morning for GMZ350-355-
     370-375.

     Small Craft Advisory until 1 PM CDT this afternoon for GMZ350-
     355-370-375.

&&

$$

SHORT TERM...Adams
LONG TERM....03
AVIATION...47
MARINE...03