Calm, cold conditions as Houston cleans up from Tuesday’s storms

Good morning. Matt has posted an excellent recap of Tuesday’s wild weather, which included what we believe to be the Houston area’s most destructive tornado since November 1992. Our thoughts are with those who suffered damage from this catastrophic event. Fortunately, calmer weather lies ahead. The story over the next two or three days will be the cold, with lows dropping into the 30s. After that we’ll return to a wetter and warmer pattern this weekend.

Wednesday

High pressure has settled over the area, and that means we will see clearing skies after a mostly cloudy start. Winds will be gusty, out of the north at 10 mph, with gusts up to 20 mph. Temperatures are starting out in the low 40s this morning, and we’re not going to get much above the mid-50s. These readings, combined with the winds, necessitate a sweater or a jacket today. Lows tonight will drop into the upper 30s in Houston, with cooler conditions inland. Winds will slacken some.

Thursday

Expect a sunny, chilly day with highs in the mid- to upper-50s. Winds will be light, at 5 to 10 mph. This will lead to ideal cooling conditions for Thursday night, with lows dropping into the upper 30s in Houston, and colder further inland. Some areas in places like Montgomery County could possibly see a light freeze.

Forecast low temperatures for Thursday night and Friday morning. (Weather Bell)

Friday

Another mostly sunny day, with highs around 60 degrees. However, as winds shift to come from the southeast, our dry and cold air mass will start to modify. Lows on Friday night will probably only drop into the low 50s.

Saturday

So long, sunshine. After the departure of high pressure and resumption of the onshore flow, we’ll see a cloudy day. Some light, scattered showers will be possible during the daytime, becoming more numerous during the evening and overnight hours as a disturbance moves overhead. With this southerly flow, temperatures will reach about 70 degrees during the daytime, with lows only dropping slightly, into the low 60s on Saturday night.

Sunday

Alas, rain chances will remain elevated at least for Sunday morning before the atmospheric disturbance finally departs to the east. Highs will likely reach the low 70s. In terms of accumulation, I expect most of the area to see roughly 1 inch of rain, give or take, during the weekend. Areas to the east, including Beaumont, could see 2 or more inches. A weak front arrives on Sunday to push overnight lows into the 50s, probably.

NOAA rain accumulation forecast for Saturday and Sunday. (Weather Bell)

Next week

Monday may only see highs in the 60s, but Tuesday and Wednesday will probably be in the 70s, with muggy and warmer conditions. After that there is general agreement in the forecast models on a stronger cold front pushing into Houston. As this is at least a week out, the details are understandably lacking. I think lows in the 30s are probably likely, and I would not rule out a freeze. If you’re thinking about planting your garden I would hold off a little bit longer, just in case.

A memorable day of severe weather for parts of the Houston area

Today was certainly a day. First off, we want to express our thoughts and best wishes to those impacted by today’s tornadoes, and we hope that the recovery process presents the fewest amount of headaches that are possible.

Tornadoes of that scale and length are not common in Houston. Since 1993, we’ve had a number of “strong” (EF-2+) tornadoes in the Houston area, most of which have been on the eastern side of the city. Today’s tornado was no exception. Here’s a map of tornadoes since 1993 that are EF-2 or greater. Only one in the immediate area rated an EF-3, which was a short tracked twister near Shoreacres in 2002.

Map of all EF-2 or greater tornadoes since 1993 in the Houston metro area. (EF-2 in yellow, EF-3 in orange) This one will likely have the longest track in recent memory. (Midwest Regional Climate Center)

In the tornado records, an EF-2 tornado has never struck the Houston area in January. Why 1993 as a cutoff? Because November 1992 had the king of modern Houston tornado outbreaks, including an F4 in Channelview, which we wrote about a few years ago.

If you’re curious, here’s a map of all known “strong” tornadoes in the Houston region since 1950.

All known EF-2 or stronger tornadoes in the Houston area since 1950. Yellow for 2, orange for 3, red for 4. We’ve never experienced an EF/F-5 in this area. (Midwest Regional Climate Center)

The National Weather Service will be sending out survey teams tomorrow morning to assess the damage and assign a rating to the tornadoes. So we will see if it was indeed a “strong” tornado or not. Remember, the rating is determined by a number of factors, not the least of which is building construction. Some poorly constructed, smaller buildings can be obliterated in a mere EF-1 tornado. Based on the initial photos of damage, I am guessing it will be at least an EF-2. But the NWS folks are the experts on this, and they’ll make that call.

Today also marked the first time a Tornado Emergency has been issued in Houston. We all know about Flash Flood Emergencies from recent years. But Tornado Emergencies certainly represent a new kind of horror for our area. They are rare and only issued when there is a confirmed, likely strong to catastrophic tornado ongoing in a populated area. If ever there were a day to issue one in Houston, today was the day. Hopefully we don’t see that again for many years.

Rain totals were rather impressive, especially in Waller County, western & northern Harris County, Montgomery County, and Liberty County where 3 to 6 inches of rain fell. (Harris County FWS)

Not to be outdone, the rainfall today was tremendous for January. We still have flooding ongoing out by Mound Creek and Little Cypress Creek in western Harris County. Several bayous ended up at bankfull or even out of their banks today. We mentioned flooding. We mentioned heavy rain. But we probably could have been a little more aggressive on the rainfall aspect of things. Today certainly qualified as a Stage 1 flooding event on our flood scale.

At any rate, we’ll know more about today’s events tomorrow. On a personal note, I want to thank the folks at the National Weather Service, as well as our other colleagues across media here in Houston for a very strong, effective messaging campaign today. Collectively, our messaging and the issuance of a Tornado Emergency by NWS no doubt helped protect lives and property in the Houston area today. For us here at SCW, this is truly why we exist. I saw several comments say that “we saw Eric and Matt really ramp up their messaging today, so it was concerning.” That’s exactly why we operate how we do. We want to be the jovial, informative but not in your face meteorologists 90-95 percent of the time. But on days like today, we get serious and down to business. Houston gets a lot of severe weather “days,” but most of them are low-end potential. They get a lot of chatter and sometimes some hype, and yes maybe on a couple of those days something happens. But we knew this had a unique high end potential for this area, and at least in a couple parts of the area, this potential was likely realized. We are grateful it was not worse. As we always say, we are here to help serve the community, and tomorrow we will be back to our normal, mostly boring selves. But when it’s really, truly time to stand up, act, and pay attention, we will make sure that message gets across. Thanks for your continued loyalty and readership. -Matt

Main line of storms now moving into Houston region with major impacts: Winds, rain, tornadoes

Good afternoon. As of about 12:45 pm CT, the main line of severe weather associated with a cold front is draped across the region from El Campo to Sealy to The Woodlands, and it is steadily progressing eastward. As expected, this system is bringing wind gusts above 40 mph, heavy rainfall, and at least one confirmed tornado and multiple other warnings. We are starting to see some street flooding in areas west of Houston, and I expect this to persist for the next few hours as rainfall rates reach 1 to 2 inches per hour. This heavy rainfall will spread into central and southeastern Houston over the next couple of hours.

Houston radar reflectivity at 12:44pm CT on Tuesday. (RadarScope)

The main line of storms should reach areas such as Sugar Land, downtown Houston, and Bush Intercontinental Airport by around 1 to 1:30 pm, and push down closer to the coast, through areas such as Pearland, Clear Lake and Baytown by around 3 pm. The system should be fully offshore, with clearing skies area-wide, by 4:30 to 5 pm. Some low-lying street flooding may persist through the evening rush hour due to the heavy rainfall, however.

I realize that the timing of these storms is extremely inconvenient for schools and day cares and other institutions that let out during afternoon hours. I cannot say much to that effect, but if your school is located inland of Interstate 69/Highway 59, conditions should be clearing out by around 3 pm, and if you live on the coastal side of this highway, this probably will be about the time you see the worst conditions.

HRRR model forecast for radar reflectivity at 2 pm CT on Tuesday. (Weather Bell)

So far this event is proceeding just about as we expected, with nasty winds, rains, and the threat of tornadoes. I expect the latter threat to peak from about 1 to 3 pm and then gradually diminish, with the rains following suit. Heavy winds will be with us throughout the night, shifting from the west to northwest overnight. If you can stay off the roads this afternoon, you should. If you have to venture out, have a radar map handy, and a way to receive emergency alerts.

Severe weather likely today as a cold front barrels into Houston: Damaging winds, heavy rains, and potentially tornadoes

Some cold fronts come into Houston like lambs. Today’s front, however, will be a lion. The prime time for severe weather today will run from late morning to about 4 pm as the front barrels into the region. A lot of the ingredients that we look for when it comes to severe weather, including instability and an energetic atmosphere, will be in place ahead of, and along with the front today. We’ll discuss the threats in greater detail below.

In the big picture, a strong upper-level system will track toward Texas, inducing a low pressure system at the surface that will create turbulent conditions. Ahead of this low, we will see strong southerly winds this morning, gusting up to 40 mph. These winds will shift to come from the west and then northwest as the front passes. Scattered showers and thunderstorms will be possible this morning ahead of the front, but the main line of storms will likely bring the most severe weather. In terms of timing, I expect the front to reach a line from Katy to Tomball to Conroe by 1 to 3 pm, push into the central Houston corridor from Sugar Land to downtown to Kingwood from 2 to 4 pm, and push off the coast from 4 to 6 pm. Let’s consider the three main threats.

Severe weather outlook for Tuesday. (NOAA)

Damaging winds: In response to the low pressure system, expect sustained winds of 30 mph or higher, with gusts of 40 to 50 mph across much of the area, especially south of Interstate 10. These winds may be strong enough to cause isolated power outages. Any outdoor furniture prone to blowing around should be put away, if possible. These kinds of winds will knock down tree limbs as well.

Heavy rain: Expect 1 to 3 inches of rain for most areas, with isolated totals of 4 inches or higher possible in areas that see storms this morning ahead of the front. The bad news is that, with the main line of storms, rainfall rates up to 2 inches per hour are possible. The good news is that the system will move fairly quickly from west to east, clearing the area. Some street flooding is possible, but I’m hopeful that roads will be clearing in terms of water by rush hour in the metro area.

Tornadoes: There is plenty of instability, lift, and shear in the atmosphere today. A lot of the parameters that we look to for tornadic activity are lighting up, especially for areas along and south of Interstate 10. But with that said, the overall environment is not ideal for tornado formation such as one might see in Oklahoma later in the spring—just supportive. The most likely time for this activity is from noon to 4 pm today, so please be weather aware at that time. Your overall odds of being impacted by a tornado are quite low, but these are high-consequence phenomena worth paying attention to.

Areas in yellow are at highest risk for a tornado on Tuesday afternoon. (NOAA)

Be weather aware: Space City Weather will provide additional updates today as warranted. We also will be providing notifications through our app (Apple version, Android version) of any significant tornadoes that form. Other good resources include NOAA weather radio and emergency alerts from the National Weather Service.

Tuesday

As noted above, today will be a windy, rainy, and nasty day. High temperatures ahead of the front will reach the upper 60s beneath mostly cloudy skies. After the front, winds will quickly shift to come from the west, and then the northwest, bringing much cooler and drier air into the region. Temperatures tonight will drop to about 40 degrees in Houston, with colder conditions further inland. With brisk, gusty winds, it will “feel” like freezing temperatures outside late tonight with the wind chill.

Wednesday

This will be a breezy and cold day, with sunny skies and highs in the mid-50s. Winds will still be gusty, up to 25 mph out of the north. Lows on Wednesday night will drop into the upper 30s.

Thursday

Winds will finally start to slacken some on Thursday, at just 5 to 10 mph, and we can expect to see highs in the mid-50s. With lighter winds, Thursday night should be the coldest of the week, with lows possibly dropping to freezing for far inland areas.

Low temperature forecast for Thursday night. (Weather Bell)

Friday

Look for mostly sunny weather, with highs around 60 degrees. As the southerly flow reestablishes itself, lows will only drop to around 50 degrees on Friday night.

Saturday and Sunday

I’m afraid the weekend outlook is not great. Both days have solid rain chances, but the most likely time is probably from Saturday evening through Sunday, with accumulations of perhaps 0.5 to 1.5 inches of rainfall. Highs will be near 70 degrees by Sunday before some sort of front cools us down a little bit.

Our next update will be posted no later than 1:30 pm CT.