In brief: It is the final hours before the Arctic freeze sets in, and we’ve got the latest information on what to expect in terms of cold and wintry precipitation, and when to expect it. The bottom line is that Tuesday and possibly Wednesday both look very iffy for traveling around Houston.

It could be worse

As I type this, the Houston Texans are kicking off against the Kansas City Chiefs in the Divisional round of the NFL Playoffs. Game-time temperatures are in the low 20s, with gusty northwesterly winds. By Tuesday morning the low temperature there is expected to be -1 degree Fahrenheit. So yes, Houston is going to get cold this coming week, but it could always be worse. Also, let’s go Texans!

Temperatures will soon begin falling

It’s fairly pleasant outside, with temperatures in the low 60s across much of the Houston region. But don’t be fooled. Winds are steady from the northwest, and as the Sun falls toward the horizon, temperatures will follow. Lows tonight will drop to around freezing in Houston, and with gusty northerly winds the apparent temperature will feel as if it is in the low 20s, at least tomorrow morning. So if you’re joining me at the Houston Marathon, bundle up, wear layers, and use the cold as motivation to go faster. Despite the cold start, Sunday will be fine in terms of getting out and about. Highs will reach the low- to- mid-40s with sunny skies.

MLK Day

Houston will likely see a light freeze on Monday morning, although some inland areas (i.e. along and north of Highway 105) could see lows drop into the mid- to upper-20s. But Monday should be mostly fine for any last minute preparations ahead of a winter storm. Highs will be around 40 degrees. I’m afraid it’s a dreary forecast for MLK Day festivities, with increasing clouds and gusty easterly winds keeping a distinct chill in the air.

Monday night through Wednesday morning

You should plan to be home by around 9 pm CT or so on Monday. Although temperatures probably won’t fall below freezing until a few hours later, we might start to see some light sleet or snow by around this time. Temperatures reach freezing levels by midnight or so, when precipitation coverage should also begin to increase.

This is the point of the forecast where we are still mired in uncertainty. The key questions are a) how much moisture will be available for precipitation to form and fall, and b) what kind of wintry mix will develop. Neither is answerable yet. For areas along and north of Interstate 10, I continue to think snow is the most likely option (perhaps 1-3 inches, or more), but we could see sleet mixed in. For areas south of Interstate 10, sleet may be more likely than snow, although we may still see some snow there. Further to the southwest, in Matagorda and Brazoria counties, we may see freezing rain as the dominant precipitation.

The bottom line is that when you wake up on Tuesday, some sort of winter wonderland (or nightmare) is going to exist outside. Snow/sleet/freezing rain is likely to continue through the morning hours on Tuesday, and possibly into the early afternoon. We may see some partially clearing skies by evening. However, temperatures will struggle to reach above freezing on Tuesday, and if they do in Houston it may only be for an hour or two. So I don’t think we’re going to get enough warmth to melt and clear streets.

Depending on how much snow cover there is overnight, temperatures in Houston will either be in the upper teens or lower 20s on Wednesday morning, which will be the coldest of the week. Virtually the entire metro area, aside from the coast, is likely to experience a hard freeze. This is going to help maintain ice or snow on area roads, and my sense is that Wednesday morning will likely once again be a no-go for traveling around the area.

By Wednesday afternoon, the combination of (slightly) above freezing temperatures and sunny skies will probably help clear roads. But it’s difficult to be certain of this right now.

The end

Highs finally get back into the mid- to upper-40s on Thursday, so at this time we think Houston will return to normal by that time. Next weekend looks to be fairly mild.

Will my power go out

Honestly, we can’t answer that. However, our supposition is that things probably will be OK in Houston in terms of electricity. ERCOT issued an update on Friday saying that while it is monitoring grid conditions closely, they are expected to remain “normal” during the upcoming winter weather. That means officials are fairly confident the grid will hold up during the colder weather. Additionally, Houston is not expected to get significant accumulations of freezing rain, which can build up on power lines and snap them. So, cautiously, we’re optimistic. But we will see.

Next update

Since I’m running the marathon tomorrow and will be cooked for the rest of the day, Matt will be covering on Sunday. We’ll have a morning and late afternoon update on the winter storm situation, similar to today.

In brief: A front is pushing into the Houston metro area this morning, and it will begin a week-long period of much colder weather, with hard freezes likely on multiple mornings, and a probable winter storm that will significantly disrupt mobility around the region on Tuesday and possibly Wednesday.

Today will be the final day before freezing temperatures arrive in the Houston metro area. Although winds will shift to come from the northwest, heralding the arrival of the cold front, we’ll see enough sunshine and lagging colder air that highs today will likely reach about 60 degrees. Conditions tonight will turn gustier and the aforementioned colder air arrives. A light freeze is possible across parts of the Houston metro area by Sunday morning.

Houston Marathon

I had the opportunity to speak with Dr. Lars Thestrup on Friday, at the start line of the Houston Marathon, which begins Sunday morning around sunrise. We discussed the cold conditions expected for runners, volunteers, and spectators on Sunday morning. Unfortunately, in addition to temperatures in the low 30s on Sunday morning, there will be wind gusts up to 30 mph.

Although there is nothing inherently unsafe about running in these conditions, they necessitate preparation. For runners, that means a cap, something to cover one’s ears, gloves, and layers. As one runs long distances, the body heats up. It may be tempting to shed a layer of clothing, but Thestrup cautioned that for half marathon runners at 8.5 miles, and full marathon runners at 14 miles, there will be a turn into a more northerly stretch of roadway. This will be a full on headwind, he said, and it will be cold. So if you’re thinking of shedding a layer of clothes, at least wait until you hit that wind, he advised. I don’t think I’ll be shedding anything, at any point.

Sunday night and Monday

Temperatures are likely to drop into the upper 20s in the Houston metro area on Sunday night, with a hard freeze possible for northern and western areas of the region, in places such as Montgomery County. So you should have hard freeze preparations completed by no later than Sunday evening.

However we expect Monday to be mostly precipitation free. Even if there is a light, misty rain temperatures should remain above freezing until Monday evening. (But it’s still going to be very cold, so bundle up for any MLK Day activities). By around midnight, if not before, temperatures will sink toward freezing and heavier precipitation is likely. That’s when things may turn dicey.

Winter storm

Travel is not advised on Tuesday. Like, please don’t if possible. We still don’t know the precise details of what types of precipitation will fall, and this portion of the forecast is still subject to change. Generally, I think snow will be most likely along and north of Interstate 10, with freezing rain and sleet more likely south of Interstate 10.

The best chance of precipitation will come after midnight and before noon on Tuesday, when temperatures area-wide will be a few degrees below freezing. We are talking about the potential for inches of snow, or significant accumulations of ice on roads from freezing rain. Daytime temperatures may briefly rise above freezing on Wednesday afternoon (or for many locations away from the coast, they may not). In short, we expect roads to be a mess on Tuesday, and with freezing temperatures on Tuesday night, probably well into Wednesday morning. I would expect significant impacts to air travel as well during this period.

How cold will it get

It looks as though Wednesday morning will be the coldest of the week. For areas north of Interstate 10, lows could drop into the 17-22 degree range, for the urban core of Houston we probably will see something in the vicinity of 20 degrees, and temperatures a few degrees warmer for coastal counties. Clear skies will allow for radiational cooling. What could really send temperatures diving, however, is snow cover. So I think the risk of colder weather than advertised above is higher for areas along and north of I-10, where snowfall is most likely. Needless to say, these cold temperatures will keep any snow or ice on the roads in place well into Wednesday morning.

When does this end?

I’m hopeful that temperatures will reach above freezing by around noon on Wednesday, but this may take longer for inland areas. Mostly sunny skies should help dry out roadways. So at this point travel around the region may become more feasible on Wednesday afternoon, but that’s not something I would guarantee at this point. A light freeze is possible on Wednesday night, and by Thursday we are well in the mid-40s so there should be fewer concerns. We may see the possibility of some wintry precipitation again Thursday night, but it’s too early to say anything sensible about this.

Preparations

Temperatures for inland areas of Houston will drop below 25 degrees as soon as Monday morning, and much of the region (with the possible exception of the coast) could see a hard freeze on either or both of Tuesday and Wednesday mornings. This is cold enough to threaten exposed pipes, sprinkler systems, and more. Here are some basic preparations to undertake:

• PLANTS. Protect tropical vegetation. Please note, with temperatures dropping this low, some vegetation will probably die regardless.
• PIPES. Protect any exposed outdoor pipes. Pipes in attics and along exterior walls of structures could freeze at these levels.
• SPRINKLERS. Sprinkler systems should be shut off and properly drained.
• ANIMALS. Prepare proper shelter and warmth for animals and livestock and make sure water sources are not frozen.

A message from our sponsor

We’re grateful to Eric and Matt for keeping us informed on the latest wintry weather expected. With cold temperatures predicted, Reliant wants to help Texans feel prepared and informed about their energy usage during extreme weather. These tips can help Space City Weather readers save energy while staying warm, regardless of energy provider:

The colder it is outside, the harder and longer your heater works to maintain the number on the thermostat.

• Check your thermostat. Many Texans have electric heaters, so freezing temperatures could result in increased energy usage and costs. We want you to be comfortable but keep in mind if you have an electric heater, setting your thermostat to around 68 degrees can help you save energy. For every degree above 68, you can typically expect a 3-5% increase in heating costs.
• Let the sun in. If the sun is shining, open blinds and shades during the day and remove any solar screens to naturally warm your home. Close them at night to help block out the chill.

Staying warm while remaining energy efficient is about keeping the heat in just as much as it is about generating it.

• Close heat escape routes. Keep the chimney damper closed when not in use and be mindful of how often you’re opening entry doors and using bathroom ventilation fans, as heat can escape through these outlets.
• Weatherstrip exterior doors and windows. With minimal effort and cost, you can seal out the cold and save up to 10% on total energy costs.

There are often items around your home you can use to stay warm and save money.

• Set your ceiling fan to rotate clockwise. This helps force warm air down into the room to create a more comfortable environment.
• Layer up. Reach for a sweater or blanket before reaching for the thermostat. Weather-appropriate clothes help reduce the demand for heat.
• Safely use space heaters. When you need to heat a small portion of your home for a limited amount of time, a space heater is a cost-efficient option but be sure to turn it off when no one is around. Using a space heater that is thermostat-controlled can prevent wasted energy.

These simple home improvement tasks can keep your heating system from working harder than it needs to and keep you from spending more than you want to on winter electricity bills.

• Protect outside faucets. Shut off exterior faucets and drain water from outdoor pipes to prevent them from bursting.
• Flush the hot water heater tank. Check the temperature and pressure relief valve to ensure it is working properly.

Visit reliant.com/wintertips for more tips on staying warm while managing your energy usage.

In brief: This post provides an update on our expectations for the winter storm next week, which is now increasingly likely to bring a hard freeze and snow to Houston. The period from Monday night through Wednesday morning could be challenging from a roads and airports standpoint.

Why we are posting on Friday afternoon

As we continue to see more model data, our confidence is increasing in a severe cold snap next week, along with the potential for measurable snowfall that could prove disruptive for travel plans on Tuesday and Wednesday of next week. Although the details remain impossible to forecast, it is now more likely than not that we will experience a serious winter storm in the Houston region four days from now.

How long do I have to prepare?

Conditions today are fairly comfortable outside, and tonight will be mild. Some very light showers will be possible overnight, ahead of the passage of a cold front on Saturday morning. However, as the colder air will be lagging behind somewhat, Saturday should be fine temperature-wise, in the upper-50s or so. By around sunset, however, temperatures will start to drop. A light freeze will be possible across much of the Houston metro area by as early as Sunday morning.

Sunday should be sunny, windy, and chilly. Temperatures on Monday morning will fall below freezing for pretty much the entire metro area, with a hard freeze (temperatures of 25 degrees, or below) possible along and north of Interstate 10. So any freeze preparations on pipes and plants should be completed no later than Sunday.

However, we likely will remain largely free of precipitation on MLK Day. So while it will be cold on Monday, with high temperatures only in the lower 40s, mobility should not be an issue. However, by Monday evening, we could start to see snowfall, and temperatures will drop below freezing pretty quickly. Travel after Monday evening may become hazardous.

Winter storm

At this time it looks like most of the precipitation that falls early next week will probably be snow. For some areas south of Houston, particularly in Brazoria and Matagorda counties, there may be more sleet or freezing rain. It’s not clear where that transition will occur, but it is entirely possible that Houston wakes up on Tuesday morning and there are 3 or 6 inches of snow on the ground. This would be the most snow Houston has received in at least two decades.

The bottom line is that we’re increasingly confident that temperatures will be well below freezing on Tuesday morning, and that there is likely to be precipitation. That means that whatever falls, is going to stick. And since temperatures may only briefly reach above freezing on Tuesday—and for some areas in Montgomery County and points north, temperatures may not rise above freezing on Tuesday—whatever falls may stick throughout the day and again for Tuesday night into Wednesday morning.

For that reason, we believe there is the potential for significant disruptions to mobility around Houston on Tuesday, and probably into Wednesday morning. Speaking of Wednesday morning, it actually looks to be the coldest of the period, with temperatures in the low 20s in Houston, and perhaps even lower depending on the extent of snow cover.

So if you’re making plans for next week, consider that much of the city could be shut down for Tuesday and part of Wednesday. Fortunately we should see sunshine on Wednesday, with temperatures warming into the 40s during the afternoon. This should help improve road conditions.

Preparations

Temperatures in parts of Houston will drop below 25 degrees as soon as Monday morning, and much of the region (with the possible exception of the coast) could see a hard freeze on either or both of Tuesday and Wednesday mornings. This is cold enough to threaten exposed pipes, sprinkler systems, and more. Here are some basic preparations to undertake:

• PLANTS. Protect tropical vegetation. Please note, with temperatures dropping this low, some vegetation will probably die regardless.
• PIPES. Protect any exposed outdoor pipes. Pipes in attics and along exterior walls of structures could freeze at these levels.
• SPRINKLERS. Sprinkler systems should be shut off and properly drained.
• ANIMALS. Prepare proper shelter and warmth for animals and livestock and make sure water sources are not frozen.

Electricity

It is beyond the scope of this website to make predictions about the availability of electricity during this winter storm. However, there are two basic issues to consider. The first is power generation at plants. This is what caused widespread power issues during the winter storm during Valentines Day in 2021. We don’t think temperatures will be quite that cold this time, and the state of Texas made significant investments after that cold outbreak. So theoretically there should be electricity available to the grid managed by ERCOT. But we’ll see.

The other step is distribution, which is the lines and poles component. If we get snow that is better than freezing rain, which can stick to power lines, weigh them down, and cause them to snap. So that will be another factor to monitor.

At this time we don’t anticipate major power disruptions during the winter storm, but certainly that is not something we can guarantee.

Our next update will come on Saturday morning.

In brief: A complicated winter storm for Houston next week continues to give us fits in weather modeling, with today’s flavor being the potential for more snow and sleet than anything else. However, we expect the forecast to continue changing over the weekend and will keep you posted. Either way, travel across the Houston area may become very difficult Tuesday and Wednesday.

Winter storm update

What has changed since yesterday? Well, a lot. The storm is back. But this time it’s a bit colder overall, which means perhaps more in the way of snow and sleet than ice. That would be good news. That said, there remains a ton of uncertainty. As a native of New Jersey and having cut my teeth forecasting in Upstate New York, I have learned to never take a winter weather forecast from models literally. This is doubly true in the South where snow and ice are generally outside the bounds of climatology, which tends to give models fits and leads to us having to caveat every single thing we say.

Anyway, here’s the NWS National Blend of Models snow forecast for the last several runs. This incorporates a bunch of models and weights them. You can see a lot of fluctuation in outcomes here.

What are we confident in? The timing. Precipitation should begin, lightly on Monday afternoon or evening. The height of the storm would likely be from about 4 AM to Noon Tuesday, with conditions slowly improving Tuesday afternoon. We are also fairly confident that Wednesday morning should be the coldest morning next week. A tropical-plant damaging freeze is likely on at least one or two mornings. An irrigation system damaging freeze is also likely if precautions are not taken.

What are we not confident in? How much of what falls where. While the models have brought the storm back into the forecast since yesterday, they remain a bit split on exactly how it plays out. We can say that in general today, it appears the highest odds of snow are north and east of Houston and the highest odds of ice are south of Houston and near the coast. Beyond that? We can’t say much. Unfortunately, that’s the most important question to answer in terms of travel conditions, school closures, etc. We will get some confidence on this through the weekend. We would think that by the morning of the MLK holiday, decisionmakers will have enough to work with.

What else aren’t we confident in? How cold it gets Wednesday morning. Snow cover is a significant component of what we refer to in meteorology as “ideal radiational cooling,” the premise being clear skies, light winds, and snow cover all contribute toward an ideal scenario for cold weather. Without snow cover next week, we’ll likely see mostly 20s for lows with a few teens north. Cold for sure, but nothing extreme. However, let’s say we get 2″ of snow across Houston. Then we could easily shave an additional 5 degrees off that, nudging us into the teens everywhere except the coast.

So there is a lot to unpack here still, and over the next couple days we should begin to see clarity. Eric and I will keep you posted on all that as it evolves with regular updates through the weekend.

Houston Marathon

I admire anyone that runs a marathon. I especially admire anyone that does so with temperatures in the 30s and a north wind gusting up to 25 mph or so. That’s what we have for you on Sunday. Temps will rise a little through the run, possibly getting to near 40 degrees by the end, but either way, it’s going to be very cold. Good luck to Eric and to all those participating in the run(s) this year!

Rest of the forecast

For those of you with weekend plans, there could be an isolated shower this afternoon or tomorrow afternoon as the front moves in, but otherwise it looks dry. Temperatures will peak in the upper-60s or low-70s today, so bust out the shorts and enjoy! Tomorrow will likely get into the 60s before the front hits in the afternoon. Temperatures will then fall tomorrow evening through the 50s and 40s and into the 30s in most of the area, with some 20s in more rural spots north of I-10 by Sunday morning. Sunday gets up to the low or mid-40s, maybe and looks windy and cold.

Monday will start in the 20s and warm into the upper-30s to low-40s. Depending on how the storm evolves, look for lows in the upper-20s and highs in the low or mid-30s on Tuesday with a breeze as well. Wednesday will probably get up near 40, but as noted above, there is some uncertainty on how cold it gets in the morning. And then a more proper warm up ensues for later next week.

Again, we will keep you posted regularly through the weekend on next week’s cold and potential winter precipitation.