After a taste of August in June, a cooler and stormier pattern will prevail this week

In brief: Temperatures in the Houston region soared into the upper 90s this weekend, but with the departure of high pressure our atmosphere has now been cracked open to storm activity. There will be a healthy chance of showers and thunderstorms all week, which will help keep a lid on temperatures.

Weekend heat

The city of Houston did not set heat records this weekend, but we came close and the temperatures outside offered a preview of what we can expect later this summer. The record highs for both Saturday and Sunday were 99 degrees (set in 1903 and 1980, respectively), and we hit 97 degrees on Saturday and 98 on Sunday at Bush Intercontinental Airport. Combined with humidity and warm nights, it felt like deep August out there. Alas the climatological ‘peak’ of summer heating in Houston is still about two months from today. Now, at least, a reprieve.

Monday

A line of storms is advancing upon the Houston region from the north, and as of sunrise it is moving into the central metro area. These storms are relatively slow-moving, and will work their way through the city and down to the coast by around noon. We are not seeing too much in the way of severe weather with these thunderstorms, but they could certainly produce some ponding on roadways and cause some brief street flooding issues.

Skies should clear out later this morning, and this should allow high temperatures this afternoon to push into the low- to mid-90s. With this daytime heating we may, in turn, see the development of some additional showers and thunderstorms this afternoon or early evening in central Houston. Lows tonight will only drop into the upper 70s.

Tuesday, Wednesday, and Thursday

This period should see unsettled weather. In the broader picture, with high pressure having departed, a series of disturbances will produce healthy rain chances each day. Again, we cannot entirely rule out the possibility of some damaging winds or other severe weather, but the primary threat during this period will be the potential for heavy rainfall.

Overall, I think this will be manageable, with most of the area picking up between 1 and 3 inches between now and Thursday. But this is Houston, we’ve reached summer, and there is always the potential for heavy rainfall that briefly backs up streets. This is a function of a) living near a very warm body of water in the Gulf of Mexico and b) living in a relatively flat city where it takes time for tropical rains to drain. But I don’t expect it to rain all the time, and some locations probably will not see rain some days.

Daily high temperatures will be dependent up cloud cover, and when and how much it rains during the afternoon hours when it typically is hottest outside. But each of these three days should see highs in the vicinity of 90 degrees, with some locations a bit above, and others a bit below. Although daytime temperatures will be a bit cooler, humidity will be plenty high, and you know those nights will be warm and muggy.

NOAA rain accumulation forecast for now through Friday. (Weather Bell)

Friday

Skies should turn a bit more sunny as we get toward the weekend. Expect highs in the lower 90s. Rain chances will still be decent however, at least 50 percent for much of the area.

Saturday and Sunday

Daily rain chances remain on the menu this weekend, probably about 50 percent each day. Overall accumulations should be quite a bit lower this weekend, i.e. I think the potential for street flooding will diminish. Probably. Expect highs generally in the lower 90s, with partly sunny skies. Nights will only fall into the upper 70s.

Next week

This overall trend should persist into next weekend; that is temperatures probably will remain the lower 90s with a decent chance of showers each day. If you’re bummed about the rain, I get it. But this is the kind of pattern that really helps set our region up nicely for the typically hot and dry patterns we can get locked into in July, or August, or both.

An early wake-up call from thunderstorms is possible on Monday in parts of the Houston area

In brief: Thunderstorms impacting the Dallas-Fort Worth Metroplex and Abilene may hold together overnight and arrive in Houston near sunrise, bringing thunder, lightning, and locally heavy rain to parts of the area.

We’re barging into your Sunday evening briefly to just offer a heads up that thunderstorms may arrive in the Houston area on Monday morning. In North Texas, there’s a pretty potent severe weather risk tonight. We’ve seen gigantic hail in the area between the Caprock and the Metroplex. Those storms are now kind of congealing into a complex of thunderstorms that will continue to arc east and southeast, possibly arriving in Southeast Texas by Monday morning.

Actual radar just before 10 PM on Sunday evening showing numerous warnings north and west of DFW and a large cluster of thunderstorms. (RadarScope)

While we are not under severe weather risk tonight, there is a marginal risk posted for Monday (level 1/5) for Houston. These storms could hold together a bit as they approach. While we do not expect gigantic hail or extreme winds like they’ve seen in some spots up north, we could see some frequent lightning, gusty winds, and heavy downpours.

A forecast radar from the HRRR model depicts what the radar could look like at 6 AM on Monday morning. (Pivotal Weather)

The HRRR model depicted above shows storms arriving right around 6 AM before dissipating by 8-9 AM. Don’t focus on specifics but rather the overall picture which shows a gradually weakening line of storms moving in. The most likely area to see organized thunderstorms is north of I-10 and west of I-45, but it’s possible that many of us see at least some rain or thunder by mid-morning Monday. Conditions would then calm down a bit Monday afternoon.

Bottom line: Don’t be shocked if you’ve got kids or pets running in a little before wake-up time tomorrow. We’d currently rate this about a 6 out of 10 on the excitable dog scale, with perhaps some higher values up toward Navasota or Huntsville or Conroe.

Eric will have more in the morning.

Houston will sweat it out this weekend before some rain chances return next week

In brief: Saharan dust will give the Houston area a hazy sky this weekend, but it will also heat up too. Look for mid to upper-90s and very uncomfortable conditions. Next week sees a cooldown as rain chances return Monday and especially Tuesday, which could be a rather stormy day.

Today and Saturday

First off, welcome back to the Saharan dust that periodically impacts our region in June and July. You’ll notice it via some haze or kind of a milky appearance to the sky when clear. It will probably impact air quality to an extent as well, though most of the dust is suspended aloft. Couple that with building high pressure and you have a truly acrid pair of summer days here. As bad as August is here, some of these June days with high heat and haze can top the charts for most miserable of summer. Expect highs in the mid-90s, with a couple spots in the upper-90s perhaps on Saturday.

Rain chances look minor but not quite zero. Yesterday saw a couple small areas pick up 1 inch or more (Friendswood and between Rosharon and Angleton as examples), and that’s entirely possible today or tomorrow. But most likely, you’ll just stay hot and dry.

Sunday

We’ll close the weekend with close to the hottest weather so far this year, as highs will try to push into the mid to upper-90s. I think that the Saharan dust this weekend may be just enough to keep us more mid-90s than upper-90s. Whatever the case, it’s going to feel close to 105 degrees at times when you factor in the humidity.

Higher end “high” heat is likely this weekend, which means it will feel very uncomfortable and heat precautions should be taken. (Weather Bell)

So, yes, for the early season this is some excessive heat. Take it easy, as we’re not yet fully adapted to these sorts of temperatures. Normally we’re just above 90 degrees in early June, not above 95 degrees. So it’s hotter than it usually is for this time of summer. Again, a stray shower is possible.

Another note, morning lows are also going to be quite uncomfortable this weekend with upper 70s to around 80 or better near the coast. We’ve been routinely seeing morning lows this week in the 80s on parts of Galveston Island through San Luis Pass down to Surfside. Some parts of inner loop Houston may also struggle to get below 80 degrees at times this weekend.

Monday

We’ll start next week in a transition. The ridge over Texas will reorient into the West, while a deep trough carves itself out in the Great Lakes. This means a return to showers and thunderstorms in Texas. On Monday, we may still be a bit sparse in coverage with the rain, but chances definitely step up from Sunday. This will knock us back into the low or mid-90s for highs.

Tuesday and beyond

Tuesday may be a very unsettled day with strong thunderstorms and heavy rainfall. It’s still a bit too early to get too into the weeds on timing or how the storms will evolve, but this day has been flagged since early in the week as a potentially stormy one. Plan accordingly.

A marginal (1/4) risk of excessive rainfall is in place for Tuesday. That may get bumped up before we get to next week, as heavy rain is very possible in spots Tuesday. (NOAA WPC)

Rain totals may reach 1 to 3 inches in much of the area depending on exactly how things evolve. But there will be some risk for higher totals as well in localized spots. We’ll track how this evolves over the weekend and report back Monday. High temps may struggle to hit 90 on Tuesday.

The coverage of rain may back down after Tuesday but rain chances will remain fairly elevated through Wednesday and Thursday.

As we get deeper into summer, let’s talk about heat and how we measure it

In brief: In today’s post we discuss the best tool we have for determining “heat” during the summer time months, something called the wet bulb globe temperature. And we’re going to need this tool for the weekend, when air temperatures should spike into the upper 90s. Next week looks significantly cooler and wetter.

Let’s talk about heat, and how we measure it

We are getting toward the spiky bit of summer—although to be clear, summer does not typically peak in Houston until late July and the first part of August—so I want to talk about heat. Air temperature is one factor in how “hot” it feels outside, certainly the most important. But other factors such as dewpoints (which indicate humidity, and are guaranteed to be high this time of year), winds, cloud cover, and Sun angle also matter as well. The most comprehensive measurement of all these factors is something known as “wet bulb globe temperature.”

That’s a funky sounding, non-intuitive name, but basically it means the heat stress you will feel when stepping outside into the sunshine at any given point in time. Matt and I feel as though this is the best tool for a “quick glance” at how truly hot our weather will be in the next several days, and when care should be taken for extreme conditions. So in the coming weeks and months we will occasionally be sharing the graphic below to indicate how hot the coming days will be. As you can see, our region’s heat will crescendo this weekend before backing down early next week.

Wet bulb globe temperature forecast for Houston for the coming week. (Weather Bell)

Thursday

Today won’t be super hot because we’ve got a chance for some lingering showers (perhaps 20 percent), and high pressure has yet to fully assert itself over the region. So expect high temperatures generally in the lower 90s, to go along with mostly sunny skies later today. Expect light winds, from the southwest, at 5 to 10 mph. Lows tonight will drop into the upper 70s.

Friday

This will be another day of temperatures in the low 90s with mostly sunny skies. We should also start to see the onset of hazier skies, as Saharan dust moves into the area after riding the trade winds all the way across the Atlantic Ocean. This will be a nuisance for people sensitive to air quality, but for most of us it will just dim the brilliance of sky a bit, and make our sunsets more reddish. Expect another warm night Friday.

High temperature forecast for Sunday. (Weather Bell)

Saturday and Sunday

Temperatures will peak this weekend, with highs in the mid-90s on Saturday for most locations, and pushing well into the upper 90s on Sunday. It remains to be seen whether the haze shaves a degree or two off the top end of these highs, but all the same it’s going to be stinging hot outside. We are also near the point of the year when the Sun reaches the highest point in the sky, so please protect your skin if you’re going to be outside between about 10 am and 4 pm.

Next week

High pressure starts to retreat next week, opening us up to a more unsettled pattern. By Tuesday or so this should bring us cloudy skies and cooler weather (highs in the upper 80s are possible). Rain chances will also be on the upswing Tuesday, with healthy chances daily for showers and thunderstorms. It’s too early to have much confidence in rain totals, but I expect much of the region to get a good soaking, with the usual threat of some street flooding with summertime rains. If you have outdoor plans during the afternoons and evenings next week, you’ll definitely want to have some back-up plans in mind. Beyond this, we can’t offer much specific in terms of which days are most likely to see rain.