textproduct: Houston/Galveston

KEY MESSAGES

- Areas of dense fog overnight into Friday morning.

- An Arctic front pushes through late Friday night/Saturday, 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. (Extreme Cold Watch in effect Saturday evening thru Monday) - Low wind chill values, near to below 0 in the Brazos Valley and the Piney Woods. - Freezing Rain/Sleet with hazardous to significant ice accumulations leading to hazardous road conditions (Winter Storm Watch in effect for most of SE Texas Saturday thru Sunday afternoon). - 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 1234 AM CST Fri Jan 23 2026

Now that we're entering the range of high-resolution model guidance, there are a few new things to discuss. The overall theme of the AFD will remain the same as the previous nights. We'll dive head-first into discussing the latest deterministic and ensemble model guidance to see if there's a bit more clarity into the winter weather potential (spoiler alert: quite a bit of uncertainty remains). We'll also discuss how the frontal timing being a bit later may lead to some interesting conditions along the coast on Saturday and how that impacts timing of a precipitation changeover to freezing rain/sleet. All of that is the why and the how of the forecast. Since there are a lot of eyes on this forecast (deservedly so), there will be two additional sections where we'll discuss how does the forecast impact you and what you can do to prepare for extremely cold temperatures and potential winter weather. You still have all day Friday...and for parts of the area you have at least half of Saturday as well to finalize and enact your prep plans to stay safe and warm.

Sciency Jargon (Why and How?) -----------------------------

Driving home just after midnight on Thursday morning was quite interesting with plenty of dense fog around. I mention that because another repeat is anticipated overnight into Friday morning. Winds are becoming light, dew point depressions are already near 1 degree and won't be getting any higher. Our normal low temperature for this time of the year is in the low to mid 60s...our low temperature overnight into Friday morning will be mainly in the mid 50s to low 60s. High temperatures on Friday afternoon will vary quite a bit depending on where you are. This is because of an Arctic cold front that will begin pushing into portions of the Piney Woods on Friday afternoon leading to high temperatures in this region to be in the upper 50s to low 60s. Elsewhere, high temperatures will range from the mid 60s to low 70s. While that's occuring, PW values will be on the rise as moisture converges ahead of the front paired with a strengthening LLJ over northern areas leading to a gradual increase in rain coverage over the Brazos Valley/Piney Woods Friday night.

Model guidance is in fairly good agreement on a slower FROPA, which doesn't push to the coast until at least Saturday morning (some model guidance indicates as late as Saturday afternoon). Friday night's temperatures remain subject to change though if the front moves in quicker than anticipated, which can happen with these shallow Arctic airmasses. A slower FROPA combined with a coastal trough developing down in South TX creates some interesting thunderstorm potential on Saturday. In this scenario, areas along the coast may find themselves in a warm sector Saturday morning complete with an axis of instability and theta-e ridging. A 30-40 kt LLJ will be overhead as well, so there will be plenty of shear to work with. This indeed means that there is some potential for strong thunderstorms south of I-10 on Saturday morning. Some of the 00Z CAMs are onboard with this scenario as they bring a MCS through our western areas on Saturday morning where the front runs into the coastal trough. This strong storm potential is also important to note because moderate to heavy rain can wash away the solutions on pre-treated roadways, which makes it less effective. Texas can't beat the allegations of wild weather swings if we go from strong storms in the morning to winter weather in the evening...

These storms and the subsequent precipitation that lingers into Sunday are brought courtesy of an upper level low that as of right now (very late Thursday night) is off of the coast of California. It will push southeastward into the Baja Peninsula on Friday, then move into northern Mexico on Saturday, and finally become embedded in the flow aloft and drift into Texas Saturday night into Sunday. There remains some uncertainty on exactly how progressive this upper level low will be, but we remain confident that there will be precipitation Saturday into Sunday. The uncertainty lies in what KIND of precipitation will be falling. After the initial wave of moderate to heavy rainfall, model guidance still reflects some mid level dry air infiltrating between generally in 500-700mb range, which just so happens to impact moisture availability in the dendritic growth zone. Even though model guidance is reflecting a dry period, there looks to be enough moisture above the surface to at least get some drizzle/light precipitation. As the LLJ expands southward along with the embedded upper level low sliding in and favorable upper level divergence, precipitation will become widespread Saturday evening into Sunday afternoon.

The question that ALL of us are still trying to figure out is how far south does the freezing line move while precipitation is occuring. Looking through model guidance is pretty much the equivalent of shaking a magic 8 ball and asking what's going to happen. One model will say "signs point to yes" and another will say "ask again later". One degree makes a big difference and literally each model has a different outcome. We do have high confidence that there will NOT be snow though, but you could argue that as the temperature column continues to cool on Sunday morning (would need some wet bulbing assistance as well) that a few flurries could mix in over the Piney Woods at the tail-end of the precip window. In uncertain situations like this, we like to take a look at things probabilistically. The probability for freezing rain/sleet is highest for the Brazos Valley and the Piney Woods, and this changeover could occur as early as Saturday midday. These areas have the greatest potential for accumulating ice with most likely amounts near 0.25". In a reasonable worst case scenario, we could see 0.25- 0.5" of ice accumulations in this region. We'll discuss what kind of impacts this can cause in the next section.

The potential for freezing rain extends further south through the Houston metro area towards the coast with a window from late Saturday night through Sunday morning. The most likely amounts are closer to trace amounts, but even trace amounts can create hazardous conditions especially on elevated roadways. A reasonable worst case scenario (if sub-freezing temperatures move in quicker than expected) would bring 0.10-0.20" of ice accumulations down towards the coast. Don't hold these exact values to heart, but I do want you to notice the variance between those two scenarios...that's why a vast amount of uncertainty remains. It's all going to be a matter of how quickly the sub-freezing temperatures move in and will they overlap with precipitation. While we're talking about this, I also want to point out that there is potential for locally enhanced precipitation due to frontogenetic banding on Sunday morning. Heavy enough precipitation would increase the temperatures a bit, but there is potential for a band of moderate to heavy rain or freezing rain...which is reflected by some of the high-res QPF guidance. A Winter Storm Watch remains in effect for most of Southeast TX Saturday through Sunday afternoon. Once we get more confidence as we get more high-resolution model guidance to look at, then we'll decide on what winter weather products will follow the watch and if there will be any additions or subtractions of counties.

As a matter of fact, there's a way for y'all to help us out in this event. Well first thing's first, make sure your family and friends are well aware of the forecast. Next, there's an app called mPING that you can download on your smartphone. This app gives you the ability to submit what type of precipitation is falling at your location. This will be most important during the Saturday night to Sunday morning timeframe and would help us keep track of exactly where the transition line of rain to freezing rain is. Now we're not asking anyone to put themselves in any danger and get out on the road to submit reports. These reports can be sent from the comfort of your home. Thanks in advance for your assistance! o7

Remember that extremely cold temperatures are also a hazard, and I saved this part of the discussion for last so that it's fresh on your mind following the winter precip talk. Last night we talked about how it's typical for model guidance to trend slightly warmer a few days out ahead of these shallow Arctic airmasses and then it trends back colder again. Guess which way the models trended tonight...colder! Multiple nights of sub-freezing temperatures are anticipated with a widespread hard freeze Sunday night and Monday night. Northern areas will also see a hard freeze on Saturday night. Low temperatures will range from the single digits to the low 20s, and that's just the air temperature. When you factor in the northerly breeze, it'll feel like its below 0 in the Brazos Valley and the Piney Woods and the single digits to the low teens elsewhere. This is mainly for Sunday night into Monday morning. Lighter winds on Monday night will make the wind chill less of a factor. However, it'll still be VERY cold with lows ranging from the single digits to the low 20s.

I want to point our attention to the daytime highs on Sunday and Monday for our northern locations. On Sunday, the Brazos Valley and the Piney Woods will not get above freezing. This means that any ice that has accumulated will remain in place going into at least Monday. Along the I-10 corridor, it's questionable on if there's a brief rise above freezing or remaining below freezing throughout the day...with the anticipated ice amounts to our north, I'd lean towards the colder side of guidance. This means the Houston metro area will be flirting right in the 32-34 degree range. Northerly winds blowing over accumulated ice generally leads to colder temperatures...yep that makes sense. High temperatures on Monday for portions of the Brazos Valley and the Piney Woods will likely remain below freezing AGAIN. This means that some of these areas will likely remain below freezing from Saturday afternoon through Tuesday...that's 65-70+ consecutive hours of below freezing temperatures. Even if temperatures rise above freezing on Sunday in and south of the metro area, any remaining wet surfaces will refreeze overnight into Monday morning.

As a result of all of the above, an Extreme Cold Watch remains in effect for all of SE Texas Saturday evening into Monday. Cold temperatures prevail throughout the week with most locations continuing to see freezing temperatures overnight (20s/30s) and highs in the 40s/50s. Additionally, we are looking at another frontal passage around midweek as well, but for now our eyes remain firmly pointed at Friday's front. We'll worry about next weekend later. By now, you should have a firm grasp on why the forecast is what it is and why uncertainty remains in the picture even this close to the event. Now let's talk about how this will impact you.

How Does This Impact You? -------------------------

Brazos Valley/Piney Woods:

Like we did above, we'll start with the ice potential and save the extremely cold temperature discussion for the tail-end as we really want y'all to pay attention to that aspect of the forecast too. The best potential for accumulating ice will be generally north of I-10, especially for portions of the Brazos Valley and the Piney Woods. This changeover to freezing rain could occur as early as Saturday midday, but is most likely Saturday afternoon. Something to note is that the initial rain before this transition to freezing rain could limit the effectiveness of the pre-treated roads. This means that hazardous travel conditions will be a concern in this region. That's not even accounting for the changeover to sleet early Sunday morning. In the section above, we talked about most likely ice accumulations being around 0.25". These ice accumulations may result in weather-related power outages. Additionally, pine trees in the Piney Woods still have their needles so they would be more susceptible to ice accumulations. If enough ice accumulates on them, then we could see large branches and/or trees falling over in this area. Be sure to have a plan in place on how to keep you and your loved ones warm if a power outage occurs. Temperatures in the Brazos Valley and the Piney Woods are not expected to rise above freezing on Sunday or Monday afternoon, so road conditions will likely be hazardous Saturday afternoon through Tuesday morning.

Multiple nights of extremely cold temperatures are expected Saturday night through at least Monday night. Low temperatures on these nights will fall into the single digits and teens. When you factor in the northerly winds, it'll feel like below 0 for most of the area with wind chill values between -5 and 3 degrees on Sunday night. Winds will be light on Monday night, so it won't feel quite as cold but still VERY cold with low temperatures in the single digits and teens. It's very important that you winterize your home in this region. Pipes may freeze and burst if not properly insulated and protected. Remember that portions of this area may remain below freezing from Saturday afternoon through Tuesday. If you plan on being outdoors in the evening to early morning hours during this period, be sure to dress in layers and protect yourself from the elements. If you would feel uncomfortable sleeping outside in these conditions, don't make your pets do it either. Don't forget about your plants too.

Houston Metro Area and Southward:

This region is tricky when it comes to the freezing rain aspect of the forecast. The freezing rain potential is definitely there for areas generally along and north of the I-10 corridor, but we can't entirely rule out freezing rain occuring all the way down to the coast. Since lots of uncertainty remains on how far south the freezing line gets, we'll keep this kind of general. Our main concern in this area is for elevated surfaces that freeze overnight into Sunday morning. This may create hazardous travel conditions over bridges, overpasses, and other elevated roadways, so it'll be important to check road conditions before traveling during the Saturday night to Monday morning timeframe. For Sunday afternoon, the Houston metro area may or may not briefly rise above freezing. Keep up to date with the forecast for the latest information and check road conditions before hitting the roadways. The period of cold rain will be longer in this area, and remember that there is potential for a round of strong storms on Saturday morning well before a potential transition to freezing rain. So, the effectiveness of the pre-treated roads may be inhibited (mainly a concern for elevated roadways). Additionally, remember that in a reasonable worst case scenario that we could see ice accumulations around 0.1-0.2" in this region, so monitoring road conditions is a must if this occurs. Even a trace amount of ice creates hazardous travel conditions.

While we aren't anticipating low temperatures in the single digits in this area, it is still very important to remember that even low temperatures in the upper teens to mid 20s can be hazardous. Wind chill values on Sunday night will be in the single digits, so it'll still be dangerously cold. This is especially true if you don't take the proper steps to winterize your home and insulate your pipes. Pipes may freeze and burst if not properly insulated and protected. If you plan on being outside in the evening to morning hours over the weekend into Monday, be sure to layer up and protect yourself from the cold. Don't forget about your pets and your plants as well.

How Can You Prepare? --------------------

There is still at least a full day to prepare for the upcoming hazardous weather conditions. If you have a plan in place and have already winterized your home, you get a gold star! If you don't have a plan, 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 safe and warm as well.

For additional winter safety information, visit 'ready.gov' and you'll see a section titled "Winter Ready" right at the top of the page where you can find all of the information above and more. Taking a few steps now to prepare makes a big difference. Follow the motto: be prepared and stay informed.

Batiste

AVIATION

(12Z TAF Issuance) Issued at 544 AM CST Fri Jan 23 2026

The first half or so of the TAFs are largely a slightly more optimistic version of persistence, with big emphasis on "slightly". By evening, with winds staying up or even increasing, have largely eliminated fog as a concern...that said, there is a low chance for a brief, but strong return of fog at the coastal terminals IF winds do weaken before the front arrives.

Another consideration at the very far end of the forecast period and around the IAH extended is the arrival of more significant rainfall along/ahead of the incoming front. Have handled this with late VCSH at CLL/UTS, and even some prevailing SHRA in the IAH extended. There is some potential for TSRA in the area generally, but best odds for that are southwest of all TAF sites, so no mentions anticipated in the next cycle unless that expectation changes.

MARINE

Issued at 1234 AM CST Fri Jan 23 2026

Light easterly to east-southeasterly winds will continue through the night along with periods of sea fog. Sea fog persisted in waves through the afternoon on Thursday and there is potential the same could occur overnight into Friday. Sea fog will become increasingly widespread overnight into Friday morning and will be dense at times. A Marine Dense Fog Advisory remains in effect through Friday morning and may need to be extended. There is potential for another round of sea fog Friday night into Saturday, but may be inhibited by the elevated winds. There is potential for a round of storms on Saturday morning ahead of an approaching front that may lead to locally higher winds and seas.

An Arctic cold front pushes offshore Saturday morning with strong 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 afternoon ahead of and in the wake of the front. A few thunderstorms will be possible on Saturday ahead of the front. Precipitation continues into Saturday night and Sunday afternoon with the potential for freezing rain in and around the bays Sunday morning. Additionally, we'll monitor for the potential for periods of abnormally low water levels in the bays during low tide cycles over the weekend and into early next week, so be sure to stay up to date with the latest forecasts.

Batiste

PRELIMINARY POINT TEMPS/POPS

College Station (CLL) 66 37 45 21 / 60 90 100 90 Houston (IAH) 68 49 54 28 / 30 70 100 100 Galveston (GLS) 65 56 60 34 / 20 60 100 100

HGX WATCHES/WARNINGS/ADVISORIES

TX...Winter Storm Watch from Saturday morning through Sunday afternoon for TXZ163-164-176>179-195>200-210>214-226-227- 300-313.

Extreme Cold Watch from Saturday evening through Monday morning for TXZ163-164-176>179-195>200-210>214-226-227-235>238-300- 313-335>338-436>439.

GM...Dense Fog Advisory until 6 AM CST early this morning for GMZ330- 335-350-355.