Month: January 2025

In brief: There have been few changes to the overall forecast today, with higher resolution modeling now coming into range on this storm and essentially validating most of what we’ve seen to this point. A legitimate, rare winter storm, with primarily snow and sleet is likely to impact most of the Houston area tomorrow night and Tuesday, causing significant travel disruption through at least Wednesday morning.

What’s new?

A few minor notes this afternoon, none of which are significant changes in thinking from this morning.

First off, the NWS has upgraded us to a Winter Storm Warning and increased their snow total forecasts for the Houston area.

They have also increased the “realistic worst case scenario” snow forecast.

Why has this happened? Well for one, modeling has continued to lock in colder with this storm, showing a sharp transition overnight Monday into Tuesday morning from plain rain, freezing rain, and a mix of sleet and snow to just sleet and probably mostly snow across the region. Secondly, high resolution weather models that only run about 48 to 60 hours out in time are now in range of the storm, confirming both that precipitation-type outcome and the potential for “banding” that will exacerbate local snowfall totals.

Again, we have to note: The snow will not fall perfectly uniformly across the region. Depending on where this “banding” sets up, that will determine places that are at risk for 6 inches or more of snow. Quite frankly, that could be anywhere in our area; we simply don’t know at this time. Recent model runs have favored the Houston through Liberty County areas, as well as Brazoria County through Beaumont areas, but that could easily change. I’d say we’ll know more tomorrow, but realistically, we may not know it until it starts.

Again, just to underscore: As long as the forecast stays on track, travel is going to be nearly impossible Monday after midnight and all day Tuesday. You will almost certainly be stuck where you are until at least later Wednesday morning. The exception to this may be the far north now (like north of Highway 105), where snow may end up lighter, no ice occurs, and roads may clear off a bit after the snow stops Tuesday afternoon. But even that may be optimistic. More to come on this.

Historical context

Realistically, this is the most significant snow threat to the region since Christmas Eve 2004. The 1895 storm stands alone as the greatest on record in Texas and Louisiana, and this storm will not dethrone that one. However, with that in mind, this has the potential to set a modern official snowfall record in Houston, which currently sits at a mere 3 inches back in February 1960. January 1940 also sits at 3 inches. While a few storms since then, including Christmas Eve 2004 have produced higher amounts in parts of the area, from a record-keeping perspective, we have a chance to make some noise.

Could it be a blizzard?

This morning I noted how wind gusts of 40 to 50 mph were possible on Galveston Island Tuesday morning with this storm. That obviously begs the question of whether or not this could end up meeting blizzard criteria. That will be hard. The technical requirements are:

1.) Sustained wind or frequent gusts to 35 mph or higher. (This will be close)
2.) Heavy snowfall or blowing snow that reduces visibility under a quarter mile. (This will be tough)
3.) Three consecutive hours of these conditions. (This will be very tough)

I’m not saying it can’t happen, but given how rigorous these requirements are, I have doubts that we’ll officially get there. But at least now you know what an official blizzard is. That said, we almost certainly will see blizzard-like conditions on the island if those winds come to fruition and a full changeover from sleet to snow occurs.

Whatever the case, we are into some seriously rare winter weather for Houston in what may end up being a generational winter storm. We will have the latest for you in the morning with revised model data at our fingertips.

In brief: A major winter storm continues to look likely for the Houston area Monday night and Tuesday, with the potential for heavy snow and sleet in parts of the region. Minor ice may occur near the coast, along with windy conditions. Travel will become difficult to impossible Tuesday morning and remain that way through at least Wednesday morning across most of the area. A significant, damaging freeze is likely Wednesday morning as well. We do warm up Thursday.

Current cold

If you’ve stepped outside, or like Eric, started running the Chevron Houston Marathon, you know it’s, um, cold.

Speaking of which, let’s check on Eric as of 8:40 am! Good luck to Eric the rest of the way!

Temperatures will recover some today, getting up into the low or mid-40s. Another cold night is expected tonight, with lows in the 20s across most of the area away from the coast. Expect a hard freeze for many outlying areas and some areas in the city too.

Remember the basic preparations you should be taking.

• 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.

And also remember to check on people that may not have adequate insulation or access to heating.

Monday

Most of tomorrow should be fine. We will see increasing clouds that may hold temperatures back a bit. Highs should be in the upper-30s. Precipitation begins sometime either Monday afternoon or evening. With temperatures comfortably above freezing, whatever falls initially may be a light rain. Resist the urge to call bust.

Sidebar: The air mass over us will be quite dry. This is important. As the rain begins falling on Monday afternoon and evening, it may fall as virga (rain that does not reach the ground). But as it evaporates on the way down, it will cool the entirety of the atmosphere from a few thousand feet up to the ground. This is essentially priming us for snow and sleet. So initially, it may fall as rain, but that will change Monday night.

The best advice we initially can offer: Be where you need to be by early Monday evening and prepare to be stuck there through at least Wednesday morning.

Monday night and Tuesday morning winter storm

As the precip increases in coverage and intensity and temperatures drop, we will see a changeover from rain to a mix of sleet and snow. I have to be honest: Much of the model data seems to be favoring a gradual change from sleet to mostly snow, especially along and north of I-10. South of there, it should still be a mix of sleet and snow, with potentially a little freezing rain near the coast or Matagorda Bay area.

A couple notes about how things will unfold.

• This storm has been strongly signaling what we call mesoscale banding or the potential for a deformation zone. In plain language? There will be widespread snow and sleet, but embedded within that will be a couple corridors of heavy snow. Those bands can see quick, heavy accumulation and snow rates of 1 to 2 inches per hour, along with the potential for thundersnow.
• That banding will also lead to a disparity in snow totals. You could, in theory, have an area that sees 2 to 3 inches and literally down the road an area that gets 6 or 7 inches.
• Sleet is the biggest risk to all this. If we end up with significant sleet and less snow, accumulations will be much lower — but travel will be just as bad. Models are trending toward more snow over sleet for much of the region, but admittedly, this is not an area where models handle things super wonderfully.
• Wind will howl on Tuesday morning, especially on Galveston Island, where gusts could exceed 40 to 45 mph. Inland gusts will be to 20 to 30 mph. Coupled with areas of heavy snow, this will create extremely poor visibility and potentially some blowing and drifting of snow. Yes, that’s an actual sentence I just typed for Southeast Texas.

When all is said and done, how much snow will you get in your backyard? The official NWS forecast is shown below.

I will say that the risk is probably asymmetrically skewed to the higher side here. In other words, there is a chance of more snow than shown, but again it will depend on sleet and exactly where those “mesoscale bands” setup. Max totals could be, could be as high as 6 to 8 inches. But those will likely be the exception, not the rule.

How about ice? Well, the official NWS forecast is one that isn’t overly bullish on ice, which is good news. Ice is where you can start to have more meaningful issues with infrastructure issues (trees, power lines, etc.). Ice of this amount would make conditions a little extra slippery but be unlikely to cause damage.

The highest ice totals are likely to be south of I-10 and in the Victoria Crossroads back toward south of San Antonio.

Travel concerns

There’s no real good way to get around this: We are inherently unprepared for a major snowstorm because, well, it rarely ever happens. Thus, you can expect that travel will be difficult to perhaps impossible on Tuesday, probably Wednesday morning, and maybe even Wednesday afternoon. We really cannot underscore this enough: Barring a dramatic forecast change, tou will probably not be able to get very far in a vehicle Tuesday or Wednesday morning. Your flight will probably be cancelled. Prepare to be stuck where you are after Monday evening.

Wednesday morning hard freeze

With ideal conditions for cold weather, including fresh snow on the ground, you can expect Wednesday morning to be very, very cold. While it won’t be super cold across the rest of Texas, locally here in Southeast Texas, we may rival one of our coldest mornings of the last few years.

Expect lows in the teens virtually everywhere away from the coast. Areas that see minimal snow accumulation will also likely be milder. This will be a hard, damaging freeze and maximum cold weather precautions need to be taken.

Wednesday afternoon should see sunshine but with snow and a bitter cold start, we will likely only get into the mid-30s or so. Another hard freeze is possible Wednesday night, albeit much less cold than Wednesday morning. And we should bounce back into the 40s on Thursday. Alas, the snow will melt.

Anyway, we’ll update you on any changes later this afternoon. But hopefully this post answers most of your questions in the meantime. Stay warm!

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.