textproduct: Houston/Galveston

KEY MESSAGES

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

- Arctic Front pushes through Friday afternoon/night, bringing various winter hazards over the weekend: - Extended periods of below freezing temperatures along with hard freezes for parts of the area Saturday night, Sunday night, and Monday night. - Low Wind Chill Values, potentially near 0 in northwestern areas. - Risk of Freezing Rain, Sleet/Ice Pellets - Hazardous marine conditions.

- Residents are encouraged to winterize their home and make plans to keep themselves and loved ones warm during the work week prior to the arrival of the Arctic air.

DISCUSSION

Issued at 1257 AM CST Wed Jan 21 2026

I already know what most of you are here to read about...given the anticipated winter weather event coming up this weekend, I'll split this discussion up into a technical overview of the synoptic environment followed by a rundown of what's expected, what's still uncertain, and the anticipated impacts (impact-based). So, if you want to skip all of the sciency jargon (please don't!), then go ahead and skip ahead to the impact-based discussion. Sound good?

Sciency Summary ---------------

It's easy to gloss over that we have a 60-80% chance of rain on Wednesday. A developing surface trough will continue moving eastward through southern portions of Texas leading to PW values surging into the 1.2-1.5" range (90th percentile: ~1.33") along and south of I-10 on Wednesday. Combine that with a frontal boundary approaching portions of the Brazos Valley/Piney Woods Wednesday afternoon and various embedded shortwaves AND speed divergence aloft AND a 30-35 kt LLJ...and we have widespread rain showers. There's definitely no shortage of lifting mechanisms Wednesday! There will be a shortage of instability though for most of the day. On Wednesday afternoon, there could be a few isolated thunderstorms along the coast, but even that's stretching it as most of the high-res guidance keeps MUCAPE generally below 300 J/kg. Rain chances stick around into Thursday along the now diffuse and stalled frontal boundary. Above normal temperatures stick around into Thursday as well with high temperatures on Wednesday in the upper 60s to low 70s and in the low to upper 70s on Thursday. High temperatures on Friday will be dependent on the progress of an Arctic front, but areas generally along and south of I-10 can expect highs in the upper 60s to low 70s. Now...onto the Arctic cold front and winter weather.

An Arctic cold front pushes through Friday afternoon into Friday night. One thing to note is that model guidance tends to underdo these shallow Arctic airmasses, which is why we tend to trend towards the colder side of guidance...this is important to note when we talk about Sunday. At the middle and upper levels, a cutoff low will approach from the southwestern CONUS leading to a surge of moisture and precipitation that lasts into early Sunday. The question becomes how quickly do we drop below freezing for a changeover to freezing rain/sleet. With a warm nose likely exceeding more than 2km aloft, chances of snow are slim to none for the majority of the precipitation window...but we'll get back to that later. Freezing rain is expected to begin as early as very early Saturday morning across portions of the Brazos Valley/Piney Woods and gradually expand southward as temperatures drop below freezing. Uncertainty remains in exactly how far south this goes though. That being said, with this forecast package I brought freezing rain all the way down to the coast given the colder model trends.

Some drier air may infiltrate around 700-850mb on Saturday afternoon, which may lead to a brief dry period (this is also uncertain). Either way, our precipitation chances extend into Sunday morning/afternoon. As the surface cold layer continues to grow on Saturday up north, a changeover to sleet is possible by Saturday afternoon. Depending on exactly how long the moisture sticks around, we could see the warm nose shrink enough to support a few flurries reaching the surface up north at the very tail-end of the event on Sunday morning, but those chances are fairly low at the moment. So, the predominant wintry precipitation for this event will be freezing rain and sleet. However, even if an area only sees liquid rainfall, the freezing temperatures on Saturday night and Sunday night could lead to elevated roadways freezing leading to hazardous travel conditions. This is a good segue into the discussion of temperatures/wind chills, which I'll lump into the impact-based portion of the AFD.

Impact-Based -------------

Sub-freezing temperatures are expected areawide Saturday night, Sunday night, and Monday night...and a few more nights into next week. Portions of the Brazos Valley and the Piney Woods will also see sub-freezing temperatures on Friday night. We are also anticipating a widespread hard freeze (temperatures below 24 degrees) on Saturday night and Sunday night with northern areas dropping into the low to mid teens. We're still talking air temperature here...when we factor in the northerly winds, things will feel A LOT colder. Wind chill values on Saturday night and Sunday night will range from near 0 degrees in the Brazos Valley to the low to mid teens around the Houston metro area. This would likely necessitate an Extreme Cold Warning, so be sure that you have ways to stay warm even in the event of power outages (mainly a concern for northern areas).

Will we get above freezing in the daytime hours over the weekend? It depends on where you're located. Portions of the Brazos Valley and the Piney Woods have the potential to see sub-freezing temperatures from Saturday morning all the way into Tuesday...that's 72+ consecutive hours of sub-freezing temperatures. Our latest forecast is currently reflecting locations around the Houston metro area seeing sub-freezing temperatures for around 40 consecutive hours, which means we are not expecting to get above 32 degrees on Sunday. This is due to the anticipated ice and northerly winds advecting that colder air southward. That also means that Monday's daytime temperatures may continue to trend downward as well if the ice remains in place. This means that travel conditions across portions of the Brazos Valley and the Piney Woods will likely be hazardous Saturday into Tuesday. Hazardous travel conditions extend southward mainly for elevated roadways during the Saturday night to Monday morning period. Pipes may freeze and burst if not properly insulated and protected.

With freezing rain/sleet potential now extending down to the coast, it's important that we further discuss the anticipated hazardous travel conditions. There is a high probability of freezing rain and sleet across the Brazos Valley and Piney Woods, and with an extended period of below freezing temperatures this means that travel conditions are likely to be severely impacted. For areas around the Houston metro area and southward, our main concern will be for ice accumulations along overpasses and elevated roadways especially Saturday night through Monday morning. Some locations may briefly rise above freezing on Sunday afternoon, but any lingering moisture will refreeze on Sunday night into Monday morning. Ice accretion and wind could also lead to power outages, so it's important that you take the time now to prepare.

There is still have plenty of time to prepare for the upcoming hazardous weather conditions. If you have a plan in place, you're a step ahead of the game! If you don't, now is a good time to make one. Be sure to know the hazards of heating your home especially in the event of a power outage. Ensure that generators are only used outdoors and away from windows, and make sure that you have a carbon monoxide detector (with fresh batteries) as well. Never use a gas stove to warm your home and never plug a space heater into anything other than directly into an outlet. Make sure your family and friends are aware of the forecast and that they have plans to stay warm as well. Road conditions (especially elevated roadways) will likely be hazardous over the weekend, so please keep that in mind before deciding to travel.

For additional winter safety information, visit 'ready.gov' and you'll see a section titled "Winter Ready" right at the top of the page. You'll be able to find all of the information above and more. Taking a few steps now to prepare makes a big difference. Be prepared and stay up to date on the latest forecast.

Batiste

AVIATION

(12Z TAF Issuance) Issued at 542 AM CST Wed Jan 21 2026

MVFR/IFR CIGs moving in with the rain band that is currently draped from SW to NE across the Brazos Valley and Piney Woods. Expect this band to continue a SE progression through the day. At the same time, have some showers moving north from South Texas this morning, impacting areas along and south of I-10. These are producing mostly drizzle compared to the showers north of the metro. Timing of arrival of northern band of showers looks to be a bit quicker than originally foreast. Currently looking at IAH experiencing SHRA as early as 13Z. Expect SHRA to continue through the duration of the day, and tapering off shortly after sunset. CIGs and VSBYs anticipated to deteriorate overnight through Thursday morning to MVFR/IFR levels. Fog may become dense at time, and may reach LIFR levels.

MARINE

Issued at 1257 AM CST Wed Jan 21 2026

Winds will remain elevated through early Wednesday morning in the Gulf waters as a coastal trough continues to develop and move eastward. As a result, caution flags remain in effect. This coastal trough will also lead to widespread Wednesday morning into Thursday afternoon. An isolated storm or two cannot be ruled out, especially during the afternoon hours on Wednesday. Water temperatures in the bays and along the immediate coast range from the upper 50s to low 60s. Southeasterly winds will gradually increase dew points into the low to mid 60s by Wednesday afternoon. This leads to the potential for sea fog Wednesday night and Thursday night. This fog may be locally dense at times, especially Wednesday night into Thursday morning.

A strong Arctic cold front pushes offshore late Friday night with strong northeasterly to northerly winds prevailing in its wake through the weekend. Small Craft Advisories will be needed for this period with sustained winds in the 25-30 kt range and elevated seas in the 8-11 ft range. Gale force gusts cannot be ruled out. Widespread precipitation is expected late Friday into Sunday behind the front. While the precipitation type along the immediate coast is anticipated to be liquid, there are some areas along the northern and central portions of the bays that have the potential for freezing rain Saturday night into Sunday morning. Additionally, we'll monitor for the potential for another round of abnormally low water levels in the bays during low tide cycles, so be sure to stay up to date with the latest forecasts.

Batiste

PRELIMINARY POINT TEMPS/POPS

College Station (CLL) 69 54 70 56 / 70 10 10 10 Houston (IAH) 69 60 72 60 / 80 30 20 10 Galveston (GLS) 67 60 67 60 / 70 30 20 10

HGX WATCHES/WARNINGS/ADVISORIES

TX...None. GM...Small Craft Should Exercise Caution until 6 AM CST early this morning for GMZ350-355-370-375.