Eric Berger

Good afternoon, everyone. We are now only about four days from the start of a massive chill down that will plunge the Houston area into a deep freeze. The forecast has not changed substantially since Matt’s update on Saturday, but we wanted to provide you with the latest thinking we have on timing and intensity. The bottom line is that we all need to be prepared for a hard freeze, and this includes taking the following precautions:

• Pipes and plumbing: Exposed pipes and plumbing needs to be winterized to prevent damage. Sprinkler systems should be shut off and drained. If you will be leaving Houston for the holidays, you should consider turning off the main water supply in case the pipes in your home burst.
• Outdoor vegetation and plants: It will be difficult to fully protect tropical plants due to the deep nature of this freeze, but providing some cover may prevent them from being killed. Plants in pots should be brought into the home or garages.
• Pets and livestock: Because the temperatures will be so low, and for many areas will remain below freezing for longer than a full day, animals should be brought into warmer spaces or they may be killed by the cold.

We know that readers have a lot of questions about the ability of ERCOT to keep power supplied to the state given the hard freeze coming into much of Texas. This is beyond the scope of our ability to forecast, but state officials have expressed confidence in the grid, and we do not expect statewide temperatures to be nearly as cold as experienced during the Valentines Day freeze of 2021. So things will probably be OK. But we can offer no guarantees.

Monday, Tuesday, and Wednesday

We will continue to see high temperatures in the 50s this week, with nighttime lows generally in the 40s. The big story for the start of the week is widespread rain showers on Monday, which will probably bring 0.5 to 1.5 inches of rain to much of the area. It looks like these will be primarily daytime showers, with chances ending around sunset or shortly thereafter as the disturbance pushes off to the east. After Monday, we can expect mostly cloudy skies to prevail until Thursday.

Thursday

On Seinfeld, Frank Costanza created the “holiday” of Festivus to be celebrated on December 23. Among the holiday’s activities was an “airing of grievances.” Well, on Thursday we’re going to get an airing of frigidness. Daytime highs may get into the 60s or possibly even 70 degrees near the coast on Thursday ahead of the front, which will sweep through the region rapidly from northwest to southeast. In terms of timing, I think late-afternoon is most likely for the front’s passage, but some wiggle room remains.

After the front’s passage temperatures will drop into the 30s quickly, with very strong northerly winds, perhaps gusting up to 35 or even 40 mph. While precipitation is probably not a concern, these winds will very quickly sap any heat if you are out of doors. Conditions overnight on Thursday are just going to be nasty outside. Temperatures will bottom out on Friday morning across the region. I think it is possible that even areas south of Interstate 10 briefly drop into the teens.

Friday

This will be a very cold day. It is possible that some areas reasonably close to the coast will briefly climb above freezing, but much of the metro area is going to remain in the upper 20s to 30 degrees despite sunny skies. Lows on Friday night will still be very, very cold, but should be 3 to 5 degrees above those on Thursday night.

Saturday

Christmas Eve will start out freezing, but with at least partly sunny skies daytime temperatures should reach the mid- to upper-30s for all but far inland areas. We can’t entirely rule out some light precipitation, but right now this period looks dry. This should make holiday travel across the region, and much the state, easier.

Christmas Day and beyond

After yet another freeze, Christmas Day should see highs in the 40s. It will be almost balmy!

Right now most of next week should bring a warming trend, with highs eventually climbing close to 70 degrees by Wednesday or so.

Lows this morning have generally fallen in the 40s, which is fairly typical for December. We’re going to see more or less winter-like weather for at least the next 10 days, with the possibility of a light freeze for inland areas on Sunday morning, and colder weather still later next week. It’s really time for that winter coal, y’all!

Thursday

This will be a prototypical winter day in Houston, with highs in the low 60s, sunny skies, and light winds. Skies will be clear tonight, with lows dropping into the mid- to upper-40s in Houston with cooler conditions further inland.

Friday

As high pressure moves off to the east we’ll start to see the return of some atmospheric moisture, and as a result clouds will start to build in during the morning, or early afternoon hours at the latest. Look for highs in the mid-60s. There is a slight chance of some light rain as a reinforcing cool front moves into the area on Friday evening. Otherwise expect lows in the mid-40s.

Saturday

Skies will clear out on Saturday, likely during the morning hours, in the wake of the front. This will be a clear, cold day, with highs likely topping out in the mid-50s. Clear skies and decreasing winds will allow for optimal cooling conditions on Saturday night, and some outlying areas are likely to see a light freeze. At this time I believe the Houston metro area will remain just above freezing, however.

Sunday

This will be another chilly day, with highs in the 50s most likely. Winds will revert to come from offshore pretty quickly, however, so we’ll start to see some clouds, and by Sunday evening skies should be mostly cloudy. Lows will drop into the mid-40s.

Monday

In response to increasing moisture levels and a low pressure system, we’ll see elevated rain chances on Monday. For most of the area I don’t think the rain will start until at least sunrise, and perhaps a bit later. Accumulations will probably be greater closer to the coast, where 1 to 2 inches is possible, with isolated higher totals. Skies will otherwise be cloudy, with highs likely topping out in the upper 50s.

Next week

We’re expecting conditions through the middle of next week to support high temperatures in the upper 50s to low 60s, with overnight temperatures generally in the 40s. The global forecast models are still strongly suggesting that a robust front will arrive with Arctic air around Wednesday or Thursday, causing temperatures to plummet a day or two before Christmas Day. Unfortunately, at this range, we don’t have the greatest of confidence in how cold things will get. The range of possibilities is this: lows might get as cold as the upper teens or they might only drop into the mid-30s. I’d lean toward a light freeze in Houston at this time, but my confidence is not particularly high. There also is a non-trivial chance of snow—at this point I’d give the metro area perhaps a 10 or 15 percent chance of a White Christmas.

The much-anticipated cool front finally rolled into Houston during the overnight hours. If you live along the coast, hold on, as the drier air is almost there. We’re also seeing some showers this morning as the front passes. They’re now primarily along the Interstate 69/Highway 59 corridor or further south, and they should continue to move down toward the coast. The bulk of this activity will be offshore by around 10 am. And so ends the warmest 10-day period December I can remember living through in Houston.

We’re still wrestling with several questions with the forecast. One of them is how cold it will get this weekend, as I think there’s a chance some far inland areas could see their first freeze of the season on Sunday morning. We’re also tracking the potential for a couple of inches of rainfall on Monday, and of course, just how cold it is going to get in Houston just ahead of the Christmas holiday. I think a light freeze, at least, is in the cards for most of the area. Will it get colder than that? Possibly. Will it snow? I’m still ballparking about a 10 percent chance for that, but ’tis the season.

Wednesday

As showers work their way down to the coast, we’re going to see clearing skies moving into the Houston area. I expect most of us will be seeing sunshine by early this afternoon, allowing high temperatures to remain in the low- to mid-60s. Winds will be out of the northwest at 10 to 15 mph, or so. But temperatures will fall off pretty quickly this evening, as winds die down. With clear skies I think most of Houston will drop into the low- to mid-40s.

Thursday and Friday

As I’ve been writing for awhile, these two days should be splendid examples of wintertime weather in Houston. Look for mostly sunny skies and highs in the low 60s. Overnight lows drop into the low- to mid-40s. Some clouds will start to return Friday afternoon or evening as moisture starts pooling inland from the Gulf of Mexico.

Saturday and Sunday

We’re going to see a chilly weekend, with highs on both days likely in the mid- to upper-50s. Saturday looks to be partly cloudy, but we should see some clearing by Saturday night and on Sunday. Conditions are supportive of temperatures bottoming out on Sunday morning, when I could see much of the Houston metro area dropping into the upper 30s, with colder conditions further inland. Both weekend days will see a slight chance of rainfall, but at this point I’m leaning toward high pressure winning out, and keeping most shower activity offshore.

Monday

Well, kids, I’m sorry. The first official day of Winter Break looks fairly wet as high pressure scoots off and is replaced by ample moisture from the Gulf of Mexico. I think the area is likely to pick up 1 to 2 inches of rainfall, with higher isolated totals, as the atmosphere lifts in response to an upper-level low. The air will be a tad muggier, and I expect high temperatures to reach the low 60s.

The rest of Christmas week

So what happens after Monday’s deluge? Rain chances look to back off on Monday night and Tuesday, but maybe not fade away entirely. We’ll see. The next couple of days look to be of the variety where we see partly sunny skies, with highs in the 60s, and lows in the 40s. Pencil that in for now. At some point—Thursday, the 23rd of December, maybe?—we’re likely to start seeing an influx of much colder, Arctic air. Still to be determined is how much of this colder air is modified or shunted east, and how much dives all the way down to the Gulf Coast.

We’re still talking about a forecast 8 to 10 days from now so, you know, it’s basically blindfolds and crayons at this point. But the vast majority of our model guidance suggests a light freeze for Houston, at least, with the possibility of some lows in the 20s. I don’t think extreme, power-sapping cold is in the cards, but it’s not something I’m ready to rule out. As always, the details of the forecast, including the chance of wintry precipitation, will come into clearer focus the closer we get.

But hey, you wanted it to feel like Christmas, right? Sometimes wishes do come true.

The month of December has started off ridiculously warm. Through Monday the region has recorded an average temperature of 69 degrees, which is 12 degrees above normal. However, after one more day the greater Houston region will see a shift toward more winter-like weather. It is not going to get spectacularly cold, rather temperatures will just slip back toward our typical December pattern of highs generally in the 60s, with lows in the 40s. The real question is what comes after that. Looking at the big picture, we can see that the coldest air mass on the planet, at present, lies over the Siberia region of Russia, where surface temperatures in some locations are in the -55 to -75 degree Fahrenheit range.

The pattern over the next week suggests that this very cold air will be drawn into Canada. After that, it’s a matter of where this air mass goes. A preponderance of modeling brings it down into the Central United States. And then? Well the question is whether the air continues diving into the deep South, toward the Gulf of Mexico, or is shunted more eastward. At this point we are talking about weather 8 to 10 days from now, so uncertainty in this is high. However, there is clearly the potential for very cold air to move into Texas, whereby we could see lows in the teens over the Christmas holiday in Houston. Low temperatures might also be 40 degrees. This far out it is difficult to forecast with any real confidence. But it is going to get cold during the last week of this year. Perhaps even very cold to the point where we need to worry about pipes, pets, plants, and power. We should have more confidence in this forecast in a couple of days.

Tuesday

In contrast to what is coming later this month, Tuesday will be absolutely balmy. Low temperatures this morning have only fallen to around 70 degrees in Houston. We’re going to see spotty showers this morning, with perhaps some thunderstorms developing this afternoon or early evening ahead of a cold front. While we cannot rule out some severe storms, at this time I expect most of this weather to remain northeast of the Houston metro area. Look for highs today to push near 80 degrees, with high humidity. Winds will be gusty, out of the south, at up to 20 mph before the front. Drier air should move in with the front this evening, perhaps reaching the metro area around 6 to 9 pm, and the coast by around midnight.

Wednesday

Lows on Wednesday morning may briefly dip into the 50s, but with clearing skies we should see highs climb into the low 60s. As moderate northerly winds back off on Wednesday night we’ll see low temperatures drop efficiently, down into the mid-40s in Houston, with colder conditions for outlying areas.

Thursday and Friday

These will be a pair of winter-like days, with sunny skies and highs in the vicinity of the low 60s. Overnight lows will be in the 40s. This period represents our best chance of guaranteed sunshine for awhile, so soak it up.

Saturday and Sunday

An additional shot of cooler air arrives on Friday night, and this will lead to chilly conditions this weekend with highs in the 50s, or possibly 60 degrees by Sunday. Both days will be partly sunny, but also have a decent chance of rain. The challenging part of the forecast is that we’re pretty confident there will be some showers offshore, but we’re not certain whether and how far this rainfall will migrate inland. So if you live south of Interstate 10, call it a 30 or 40 percent chance of light rain each day, with lesser chances further inland.

Monday

An onshore flow looks set to resume on Sunday, and this will probably set the stage for a wetter Monday ahead of the region’s next cold front. How wet? I would not be surprised to see 1 to 2 inches of rainfall on a warmer day when highs climb into the 60s, because there will be plenty of atmospheric moisture to work with.

Tuesday and beyond

We’ve got a cold front penciled in for Tuesday of next week, which may drop lows into the 30s for a few days. After that the most plausible scenario is a shot of even colder Arctic air, as discussed at the outset of this post. It becomes really difficult to parse details beyond this, but the overall pattern does support the influx of much colder air just prior to, and on Christmas Day. I think the atmosphere probably will be too dry to squeeze out any snowfall, but at this point I would not entirely rule out a white Christmas in Houston. I just would not put the chances at much higher than 10 percent.

Even though the holidays are coming, rest assured that Matt, Maria, and I will be covering this all for you as much as needed.