Eric Berger

In brief: This post recaps the macro conditions that set the stage for our strong to extreme storms during the month of May. The week ahead looks warmer, with highs in the low- to mid-90s, but possibly some slightly lower humidity by the weekend. Rain chances are low for awhile.

May storms

The month of May ended over the weekend, and in Houston we will remember it as one of the stormiest spring months in memory. I don’t have all of the answers for why strong storm system, after storm system rolled through Houston bringing violent winds, some hail, and occasionally some tornadoes. But as we look how the month of May ranked, temperature-wise, we can glean one big clue.

For the Houston area, the month generally ranked among the 10 warmest Mays on record. However, when we look at the western United States, particularly Colorado and Wyoming, we see colder temperatures. This is important because storm systems that develop in the Great Plains states, and then sweep eastward and southward, are driven by both geography—where the mountains meet the plains—as well as temperatures. That is, the collision of warm, humid air from the Gulf of Mexico with the colder air of the northwest United States is the cauldron in which mesoscale convective systems are born. This May, that temperature gradient was sharper, creating an environment in which the clash of these air masses produced still more violent storms.

Monday

Today will be similar to Sunday, which is to say that skies will be partly sunny with high temperatures generally in the low 90s. Winds will be from the south at 10 to 15 mph, with higher gusts. Houston isn’t entirely out of storm territory, but anything that develops in Houston should be isolated, and rain chances are likely only about 10 percent. Further north, along and north of Highway 105, storm chances this afternoon and evening are a bit higher. Tonight will be warm, with lows only briefly reaching the upper 70s for most locations.

Tuesday

Skies will be mostly sunny on Tuesday, with highs in the low 90s. There’s a bit of uncertainty, as there are hints of another modestly organized storm system in the models approaching the city on Tuesday morning. However, I’m fairly bearish on this actually happening, so I expect we’ll remain dry. But it’s possible we’ll see a few showers and thunderstorms during the morning hours. Winds will again be from the south, but perhaps gustier, up to 25 mph or so.

Wednesday, Thursday, and Friday

These will be warmer and sunny days, with highs in the mid-90s. Do you like summer in Houston? Then you’re in luck. Rain chances aren’t zero, but they’re on the order of 10 percent each day.

Saturday and Sunday

A slightly drier air mass may work its way into the region this weekend. Highs are likely to still reach the mid-90s, but the humidity may be slightly lower. (You can see this reflected in the wet bulb globe temperature forecast for the weekend). Lows should get down into the mid-70s in parts of Houston, so the evenings may feel that bit more comfortable.

Next week

I don’t feel particularly confident in the forecast next week, but some rain chances may return to the forecast by Monday or Tuesday. Nothing crazy, mind you. But after a sunny week and weekend, some rain probably would not be unwelcome.

In brief: While the probability of severe weather is lower today, the Houston region is still likely to see the development of storms later this morning, lasting through the afternoon hours. Please be weather-aware if you’re out and about today.

Welcome to June, and the beginning of the Atlantic hurricane season. Speaking of which, on our companion site The Eyewall, Matt lays out some reasons by you should be wary, but not decidedly worried about what’s expected to be a frenetic season. The good news is that things look quiet for now.

Today’s weather may not be quiet in Houston, however. As of 9:30 am this morning, a mass of showers and thunderstorms has developed to the southwest of Houston, near Palacios and Matagorda Bay. Generally, I expect these storms to lift to the north-northeast into the metro area later this morning and throughout the afternoon hours.

What does that mean? If you have activities planned from around 11 am to 7 pm today, you should be weather-aware. Considering variables such as atmospheric instability, I don’t think we’re looking at bedlam. Yes, there’s the potential for small hail or damaging winds, but conditions are not ideal for severe weather. So it’s a possibility. Perhaps a bigger concern is that some of the storms today may be slow-movers, so a few parts of Houston may see some rain bullseyes of 2 to 4 inches and some street flooding. For most of us, however, I think the impact will be less. In any case, it does appear as though things will start to clear out with the loss of daytime heating this evening.

I don’t feel overly confident in the forecast for Sunday, but it does seem possible that we could see some scattered to isolated showers and thunderstorms during the afternoon hours, again, with daytime heating. Coverage should be less than today. If the forecast changes significantly for later today or Sunday, we’ll update as warranted. If not, we’ll see you on Monday morning.

In brief: Expect quiet weather this evening, but the Houston region is likely to see another round of showers and thunderstorms on Saturday, and possibly Sunday as well before high pressure takes control.

Good afternoon. The round of strong to severe thunderstorms that worked its way through Houston this morning has helped work over the atmosphere such that we’re seeing quiet conditions this afternoon. Due to this more stable atmosphere, we are likely to see continued fair weather this evening and into the overnight hours—which is good news if you have outdoor plans, graduation celebrations, or other activities.

The question becomes, then, what happens on Saturday?

Although Friday night into early Saturday morning will most likely be calm, that does not mean we’re done with storm chances. It looks as though we’ll see an additional round of showers and thunderstorms on Saturday. Some of these could become severe, but I anticipate they will be less severe than those on Friday morning, with the main threat being damaging winds, and possibly some slight chances for hail. In terms of timing, I expect these storms to flare up during the mid-morning hours in coastal counties before spreading inland. Heavy rainfall may briefly cause some street flooding. I’m hopeful we’ll see a reprieve in stormy weather on Saturday evening, and again during the overnight hours.

As for Sunday, storm chances will diminish, but I’m not ready to write them off entirely as high pressure won’t really be in place yet. Another round of showers looks to be possible, but not overly likely, during the morning hours of Sunday. The rest of next week still looks mostly sunny, with highs in the low- to mid-90s.

We’ll have another update on Saturday morning to fine tune the storm forecast.

In brief: In the absence of high pressure, Houston’s atmosphere remains open to the passing of shortwave disturbances over the coming days. At this point Friday looks like it could see the most organized showers and thunderstorms, and the greatest chance of damaging winds, hail, and heavy rainfall. By Sunday storm chances start to wane, with next week looking warmer and mostly sunny.

Thursday

Skies will be partly sunny today, with high temperatures in the upper 80s. Like on Wednesday, this daytime heating should lead to the development of showers and thunderstorms during the period of 3 to 9 pm. Some of these could become severe. However, at this time I think chances are better along and north of Interstate 10, rather than closer to the coast. (Speaking of coastal areas, I wanted to shout-out the senior class of Clear Creek High School, where I’ve gotten to know a lot of great kids. Enjoy graduation this evening!) Lows tonight will be in the upper 70s.

Like on Wednesday, we’ll be monitoring the potential for storm development closely, and if the forecast for today or Friday changes significantly we will update the site accordingly this afternoon.

Friday

At this point it looks like a more organized round of storms will move into the Houston area on Friday morning, likely sweeping into Houston around sunrise, give or take. This system will offer the best chance of severe weather, including damaging winds and hail. Depending on the severity of this system, there may be a second round of storms with daytime heating in the afternoon. (I.e. if the morning storms are weaker, there will be a better chance of a second round later in the day). Bottom line: If you need to be out and about tomorrow morning, be weather aware.

I would guess that most of Houston see an additional 1 to 2 inches of rain through Friday, but my concern is for higher bullseyes in stronger thunderstorms. At this point, Friday evening looks to see a break in showers. Daytime highs will be in the upper 80s.

Saturday

Our atmosphere will remain unsettled into the weekend, especially for Saturday. I don’t have much confidence in the details yet, but we could see another round of showers during the daytime on Saturday. These storms, at this point, do not look particularly severe. Highs, otherwise, should be around 90 degrees with partly sunny skies.

Sunday

We may see some additional showers on Sunday morning, but I’m far from confident in that. Skies, otherwise, should be partly sunny with temperatures in the low 90s. If you have outdoor plans later in the day or evening on Sunday, I’d feel at least somewhat confident in them.

Next week

As high pressure settles in next week we’ll revert to mostly sunny skies and warmer temperatures. Highs should be pushing into the mid-90s toward the end of the week. Rain chances are low, probably close to zero. So it goes in summer under such a pressure system.