Eric Berger

In brief: This morning’s update discusses the tornado outbreak on Saturday, and looks ahead to milder weather this week. We also discuss the increasing potential for much colder weather beginning next Monday in the Houston region. But just how cold will it get?

Tornado recap

The National Weather Service has completed its preliminary analysis of six tornadoes in the greater Houston metro area on Saturday, December 28. These included an EF-3 tornado near Porter Heights and Splendora, which had a ground track about 10 miles long, and an EF-2 tornado in Brazoria County with a ground track of nearly 9 miles. This latter tornado killed one person and injured five people, and also did major damage to Walt Disney Elementary School in Alvin. Many teachers lost educational materials due to the tornado, and you can donate to support their efforts to recover here.

Houston experienced three days of violent weather in the last week, which is a rarity for this time of year. Fortunately conditions should settle down now. Our next big concern is the potential for a hard freeze about a week or 10 days from now, which I’ll discuss further below.

Monday

With air temperatures and dewpoints both in the upper 50s this morning, we are dealing with marine fog across parts of the metro area. This should dissipate later this morning as temperatures rise. It will be a warm day, with sunny skies and highs of around 80 degrees. Southwesterly winds will aid in the flow of warmer air into the area. Lows tonight will generally be in the 60s through the evening hours before a cold front (likely without precipitation) pushes down into the area after midnight.

Tuesday

We should awake to cooler conditions, in the 50s, on Tuesday morning. Highs will likely peak in the mid- to upper-60s for most areas with sunny skies and drier air. If you’re going to be out and about on New Year’s Eve, expect cool temperatures in the lower 50s, with a northwest breeze. Besides the cooler conditions, there should be no other concerns for New Year’s Eve. Lows on Tuesday night will drop into the mid-40s.

New Year’s Day

We will start the new year cold and clear, with highs likely only reaching the lower 60s. Expect to see sunny skies.

Thursday, Friday, Saturday, and Sunday

The second half of the weekend will bring a gradual warmup into the area, with partly sunny skies and highs in the upper 60s to lower 70s. As atmospheric moisture levels rise we’ll see some low-end rain chances each day, but accumulations at this point do not look overly impressive. By Sunday or Sunday night the next cold front should push into the area, potentially setting the stage for a significantly colder period.

Potential for a hard freeze

Since Matt addressed the possibility of a hard freeze on Friday, we have continued to gather more data, and the story has changed somewhat. The bottom line is that we could see our first Arctic air of the season next week, although the details of just how cold things get are still fuzzy.

For Texas, it’s the usual story in winter. A significant slug of colder air is going to drop down into the eastern United States from Canada. This differs from the more zonal flow we have seen this winter to date, in which modified colder air comes down from the Pacific Northwest, rather than the really cold stuff directly down from northern Canada. The question for Texas is whether this Arctic air dives down into the state, or gets shunted off to the southeast. This time I think we’re going to get plenty of colder air next week, but we are unlikely to see the worst of it.

With all of that said, my sense is that an initial surge of colder air next Monday will drop area-wide lows into the 30s for much of the Houston region (the coast may be warmer, and the usual suspects for inland areas may see a light freeze). Then, with one or two additional pushes of colder air, temperatures are just going to get colder through the week. Since we’re talking about a period 10 days from now it’s impossible to say how cold, but at this point I don’t think we can rule out lows in the 20s by Friday or Saturday of next week. Whether that’s lower 20s or upper 20s, we just cannot say. If we get some precipitation there is a low-end chance of some snow or a wintry mix toward the end of next week, but the odds of this happening are probably on the order of 10 percent at this point.

Anyway, this is something we’ll be watching all week, and we’ll keep you informed as we go along.

In brief: This short update is to inform you that potentially severe thunderstorms are on Houston’s doorstep, and will be impacting the region this afternoon. Please be weather aware for the next several hours.

Good afternoon. This is just a short post to note that, as expected, a line of strong thunderstorms is advancing into the Houston metro area as of 1:15 pm CT. We anticipate the period of most threatening and severe weather will occur from now through about 7 pm CT. Here’s what to expect during that time:

• A line of storms presently from El Campo to Sealy to Navasota will steadily progress eastward, likely reaching central portions of the Houston metro area between 2 and 4 pm CT
• These storms will then push steadily eastward, pushing offshore and to the east of Houston by 6 to 8 pm CT
• The primary threats from these storms include heavy rainfall that may briefly flood streets, damaging winds, hail, and possibly tornadoes
• To account for the threat of tornadoes, the National Weather Service has issued a Tornado Watch for the entire Houston metro area through 7 pm CT this evening.

Drier air will be moving in behind the storms as a weak front pushes into Houston overnight. Friday morning will (briefly) feel cooler and drier with temperatures in the lower 50s. Don’t get used to the cooler weather, as the onshore flow returns pretty quickly, with Saturday climbing back into the upper 70s. We’ll have full details in our forecast tomorrow morning, but until then, please be weather aware this afternoon and early evening!

In brief: The atmospheric setup today is favorable for severe weather, including hail, damaging winds, and possibly tornadoes. The main threat will come from late this morning until early this evening. After the storms, Houston’s weather turns much calmer for the weekend.

Thursday

After a relatively mild Christmas Day, the atmosphere above Houston is recharged for another round of storms today. Rising moisture levels will spark some scattered showers this morning before an atmospheric disturbance advances into the area. Accordingly, we should start to see some thunderstorms later this morning, and likely becoming more widespread by around noon or so. We will then see the threat of severe weather until about sunset this evening, or shortly thereafter.

What does that mean? Well in addition to heavy rainfall, there may be enough rotation in the atmosphere to support a few tornadoes, enough updraft to support hail, and downdrafts to promote high surface winds. On top of this, although much of the area probably will see about 1 inch of rain, higher accumulations are definitely possible and this may lead to some localized street flooding. The bottom line is that, from late this morning through the early evening hours, you should be prepared for the possibility of disruptive weather.

Skies, otherwise, will be mostly cloudy. Expect highs in the mid-70s. Some moderately drier air will move in with a weak front tonight, allowing for lows to drop into the upper 50s in Houston.

Friday

Friday should be mostly sunny and pleasant, with high temperatures in the low- to mid-70s. Winds will generally be light. As the short-lived front washes out, lows on Friday night will be a bit warmer, in the lower 60s.

Saturday

This will be a warmer, slightly more humid day, with high temperatures in the upper 70s. A front will move through Houston on Saturday evening (exact timing to be determined) and this may bring with it a broken line of showers sometime during the day. I’m not particularly bullish on the potential for showers, but we’ll see. Anyway, Saturday night should be cooler, in the 50s.

Sunday

This should be a lovely day, with highs in the lower 70s, sunshine, and drier air. Lows on Sunday night will drop into the 50s.

Next week

We should see lots of sunshine next week. We’ll be a bit warmer on Monday, but a front looks set to arrive late on Monday night, or New Year’s Eve, to begin the process of bringing temperatures down to more typical levels for this time of year. My early guess at temperatures for the night of New Year’s Eve calls for temperatures in the 50s, with probably mostly clear skies, and breezy conditions. So while it very likely won’t rain during New Year’s celebrations, it could be chilly. Lows should fall into the 40s for most of next week, in the new year.

In brief: Good morning on this fine Christmas Day. Santa sure brought the thunder last night, didn’t he? We are interrupting your holiday with a short update to note that another round of storms is possible Thursday as we see a similar setup: Lots of moisture in the atmosphere and a weak frontal boundary.

Christmas Day

The storms have cleared our area to the east, and we’ll see a calm day today. Look for high temperatures around 70 degrees, with partly to mostly cloudy skies, and possibly a few light, lingering showers. Tonight will be mild, with lows in the lower 60s. The bottom line is that, soggy soils aside, any activities today and this evening should be fine.

Thursday

As atmospheric moisture levels rise, we’ll see the possibility of some fog on Thursday morning to go along with some fairly humid conditions. The problem is that we’re going to see another disturbance propagate down from the northwest during the daytime. What this likely means is that the Houston region (particularly coastal areas, maybe?) will see the potential for some scattered showers and thunderstorms.

Then, later on Thursday afternoon or early evening, we’ll see a line of storms move down from the northwest to southeast. I’m not convinced these storms will be as organized as what we saw early on Christmas morning, but there’s the potential for some damaging winds, more hail, and briefly heavy rainfall. They might also strike during rush hour. The storms should clear the area before midnight.

Afterward, Friday and the weekend looks pretty pleasant. We’ll have all the details on that in our forecast on Thursday morning. Until that time, have a wonderful holiday!