textproduct: Houston/Galveston

KEY MESSAGES

- Rain chances increase Wednesday in association with a weak surface trough and some upper disturbances.

- Arctic Front should sag into the region Friday and Friday night, bringing various winter hazards over the weekend: - Some prolonged temperatures and potential hard freezes. - Low Wind Chill Values, potentially between 8-20 degrees. - Risk of Freezing Rain, Sleet/Ice Pellets - Hazardous marine conditions.

- Residents are encouraged to winterize their home during the work week prior to the cold weather arrival.

DISCUSSION

Issued at 1236 AM CST Tue Jan 20 2026

A weak frontal boundary will be sagging southward thru the Brazos Valley down to about the Columbus-Edna area today then stall/weaken as it looses its southward push. This remnant boundary/trof, pooling moisture to its east and some weak impulses aloft should be enough to generate some light precip across the region Wednesday into Thursday.

Arctic airmass will begin spilling into parts of the region Friday and Friday night bringing increasingly cold temperatures and wind chills to the region over the weekend as a 1050mb-ish high drops SSE out of Canada into the Plains and Midwest. As this occurs, a mid/upper trough will be making its way eastward from the SoCal/Baja region along with a moist, active southern stream overspreading the colder surface airmass and likely bringing a swath of precipitation to the region Friday, Saturday and parts of Sunday.

Of course, the column temperature profile at those times will determine who sees frozen precipitation, what type, how much, and what times. I'm not going to regurgitate what every 00z deterministic model is showing...as it'll be changing with every 6-hour run cycle thru the week. But here are a few highlights on the broad picture and some talking points at this time:

- Guidance has been showing a consistent signal for an Arctic airmass overspreading the area this weekend. Freezing temperatures, possibly some longer durations of sub-freezing readings, are likely. Potentially dangerous wind chills too.

- Precipitation is also looking likely. As we get closer to the event, and we get into the window of some of our better high resolution modeling (late work week or so) we should hopefully have some better confidence as to what the atmospheric temperature profile might look like and what form the precip might take. Have undercut the NBM and ensembles in regards to surface temps already. For what they're worth at this point (not a whole lot), forecast soundings point to decent shots of freezing rain and maybe some sleet, esp north of I-10...and a non-zero chance further south. For planning purposes, I might focus upon late Friday evening into early Sunday afternoon.

- Historically speaking, which may or may not be useful for this particular event, these shallow cold airmasses typically arrive faster and are colder than global guidance indicates. It's also not uncommon to see some general consistency for several days, then some runs where guidance looses the signal, before it magically reappears in later runs. Try not to follow any individual model suite/run...or individual social media snapshot. Trends are your friend.

- Residents have time to winterize your home (pipes, sprinkler systems, etc) for the next several days in your shorts and flip- flops before the cold air arrives. Recommend using this time to do so.

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AVIATION

(00Z TAF Issuance) Issued at 520 PM CST Mon Jan 19 2026

VFR conditions will prevail throughout the TAF period. Southeasterly winds generally between 7-12 kt this afternoon will trend towards becoming light and variable overnight. Winds on Tuesday will be predominantly easterly in the morning then becoming east-southeasterly in the afternoon. Wind speeds will generally be in the 7-12 kt range once again with occasional gusts around 15 kt especially in the afternoon. While VFR conditions persist, there will be some mid to upper level BKN to OVC clouds building in throughout the day on Tuesday.

Looking ahead to Tuesday night into Wednesday morning, model guidance indicates the potential for MVFR ceilings for terminals north of I-10. This coincides with increasing chances for scattered rain showers on early Wednesday morning.

Batiste

MARINE

Issued at 1236 AM CST Tue Jan 20 2026

Mariners should remain mindful of negative tide levels again today, mainly across the northern bay areas around low tide cycles. A tightening pressure gradient will lead to some increasing Gulf winds today. The next shift may need to consider hoisting the Small Craft Caution flags in the Gulf. A weak coastal trough is expected to develop and move eastward bring periods of showers on Wednesday into Thursday. Patchy fog is also possible Wednesday night and Thursday morning, but conditions do not appear overly favorable for prolonged stretches of the dense variety. An Arctic cold front is expected to push into the coastal waters late Friday or Saturday bringing hazardous marine conditions: a much colder airmass, strong north winds and building seas through the weekend. Periods of precipitation are anticipated through Saturday. Advisories are likely, and Gales cannot be ruled out. Mariners are advised to keep up with the latest forecasts. 47

PRELIMINARY POINT TEMPS/POPS

College Station (CLL) 68 39 63 56 / 0 0 0 30 Houston (IAH) 67 44 67 56 / 0 0 0 20 Galveston (GLS) 65 55 65 59 / 0 0 0 10

HGX WATCHES/WARNINGS/ADVISORIES

TX...None. GM...Low Water Advisory from 2 PM to 6 PM CST Tuesday for GMZ335.