021
FXUS64 KHGX 180606
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
1206 AM CST Thu Dec 18 2025

...New DISCUSSION, MARINE...

.KEY MESSAGES...

- Stay alert when traveling overnight and through the morning
  commute, with a dense fog advisory in place across Southeast
  Texas.

- Friday will provide one day with cooler and much drier
  conditions after a cold front moves through later on Thursday.
  Though noticeably cooler than the days around it, temperatures
  will still ultimately end up near seasonal averages.

- Beyond Friday, expect a long stretch of warmer than normal
  conditions through the weekend and deep into next week. Record
  breaking warmth is possible, with Sunday currently appearing to
  be the hottest day of the stretch.


&&

.DISCUSSION...
Issued at 1206 AM CST Thu Dec 18 2025

The forecast, briefly:
Foggy night ahead
Briefly cool, dry on Friday
Then hot for awhile.

If one only has 17 syllables to work with, that should handle it
pretty well. With some more syllables, we can dig into things a
little more. At the moment late this evening, dense fog is
beginning to spread out from its origin on Galveston Bay. Much of
the Houston metro and Galveston Bay area is seeing visibility
around or less than a quarter-mile, and more of the area is
beginning to join it. Dense fog is a bit less of a slam dunk the
farther north and west of the metro you get, but there`s enough
confidence for the dense fog advisory that`s been put in place for
all of Southeast Texas (plus bays and nearshore waters, but more
on that in the marine section below) through the morning hours.

We should see gradual improvement in the fog through the morning,
and one more generally warm and humid day Thursday until a cold
front sweeps through the area later in the day. High temps in the
far north will depend *very* strongly on the precise timing of the
front, as places like College Station, Madisonville, and Crockett
will see the front move through earliest in the afternoon. If it
comes through as forecast, that should be enough to chop temps off
in the lower 70s. If it`s just a couple hours slower, those
locations will join locations a little closer to the coast in the
middle to upper 70s. The coastal plain will likely be the hottest
part of the area, thanks to the front likely arriving too late to
chop off temps before the diurnal peak, and may even benefit from
southwest flow lining up with high temps to pump up temps a little
bit more to around 80 degrees.

Once the front is through the area and off the coast, though,
we`ll see a surge of north to northeasterly winds usher in a shot
of cooler, much drier air. The drier air will allow temps to fall
as low as the upper 30s way up in Houston County, and down to
around 50 degrees at the beaches. After the cooler start, Friday
should be cooler with highs in the 60s area-wide. I am afraid I`m
making this sound more impressive than it is. After all is said
and done, all this front is going to do is take Friday down to
seasonal averages for mid-December.

That isn`t even getting into how long the cooler temperatures
last, and that`s where the real disappointment is going to come in
for winter lovers of the area. The happy times ahead are really
for the heat misers, as solid ridging will build in for the
weekend and deep into next week, allowing well above-average
temperatures to persist through the pre-holiday week (and though
Christmas itself lies just beyond our forecast period, spoiler
alert: no change there, either). Every once in a great while,
Houston gets a White Christmas in the way tradition means. This
year, we`re more likely to see a White Christmas in the way the
Texas Gulf Coast is more used to - through fog. Our gifts?
Potentially record highs, with Sunday standing out as a particular
target as mid-level ridging passes nearly directly overhead. Will
we pull it off? Probably...not? Houston looks like the best
candidate, with Sunday`s forecast three degrees below the record
high. But confidence seems to be growing in coming in just under
records, as we now have to step up to the 90th percentile MaxT
values in the NBM distribution to match the record there. Still
on the table, not an unreasonable outcome, but would need things
to definitely trend towards the hot end of the model envelope.

The story remains much the same deep into the new week. Warm,
humid, definitely well above average temperatures at night and
during the day, but...probably...daily records are safe. That is
very much a not confident probably in there. We`ll likely be on
thermometer watch all week down here. Beyond that, those at the
coast will also need to be on the lookout for fog potential. The
weekend looks like the best time for this, but will largely come
down to a race between dewpoints and how quickly the bays and
nearshore waters warm up in this stretch. I tentatively draw in
patchy coastal fog each night from Saturday night onward, but this
will have to be consistently re-evaluated going forward.

&&

.AVIATION...
(00Z TAF Issuance)
Issued at 610 PM CST Wed Dec 17 2025

Mixture of IFR to VFR ceilings/visibilities as we head into
Wednesday evening, but expect widespread IFR/LIFR conditions to
develop over the next few hours. The onset of fog may end up being
a few hours earlier than anticipated based on current trends. In
addition to low ceilings, widespread dense fog is expected to
develop across the area. This is most likely to occur between a
05Z-15Z window going into Thursday morning. While visibilities
will begin to improve after 15-16Z, ceilings will take a bit
longer with improvement to MVFR around 18Z before widespread VFR
conditions return around 20Z as a frontal boundary pushes through
the area. Expect winds to gradually shift from southwesterly to
northerly during the afternoon with wind speeds generally in the
7-10 kt range. For the northern terminals, could see occasional
wind gusts up to 20 kt during the afternoon hours.

Going into Thursday evening/night, we will be monitoring the
potential for LLWS as a LLJ develops over the area in the wake of
the previously mentioned frontal boundary. Winds around
2,000-4,000 ft will be around 35 kt generally after 03Z/Friday,
which could potentially bring ~35-40 kt of LLWS at FL020.

Batiste

&&

.MARINE...
Issued at 1206 AM CST Thu Dec 18 2025

Relatively light east to southeast winds are expected through
tonight, along with areas of fog. Fog may be dense at times,
particularly in Galveston Bay and Gulf waters immediately adjacent
to it. Fog will be in place through the night into tomorrow
morning before gradually improving. A front pushes offshore
Thursday evening, bringing gusty north to northeast winds
overnight Thursday into early Friday morning. If the front is on
the slow side, there may be an hour or two where fog may redevelop
as the sun goes down, only to be swept away when the front moves
through.

Once the stronger northeasterly winds crank up behind the front, a
Small Craft Advisory may be warranted on the Gulf waters. Winds
weaken and veer on Friday. The potential for overnight and morning
fog will need to be monitored for this weekend due to the quick
return of onshore winds. How intense any fog episodes will get
will depend strongly on wind fetch and how quickly moisture
returns to the area relative to water temperatures.

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)  61  76  41  66 /   0   0   0   0
Houston (IAH)  61  77  47  66 /  10   0   0   0
Galveston (GLS)  62  71  54  64 /  20   0   0   0

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...Dense Fog Advisory until 9 AM CST Thursday for TXZ163-164-
     176>179-195>200-210>214-226-227-235>238-300-313-335>338-
     437>439.

GM...Dense Fog Advisory until 10 AM CST Thursday for GMZ330-335-350-
     355.

&&

$$

DISCUSSION...Luchs
AVIATION...Batiste
MARINE...Luchs