Eric Berger

Good morning. As anticipated, much of the area on Wednesday along and south of Interstate 10 recorded rainfall. Today, widespread showers will extend across most of the rest of the region as an atmospheric disturbance moves in from the west. This will provide lift for the very moist air at the surface, and should lead to some healthy showers and thunderstorms.

We’ll see some additional rain chances on Friday and Saturday, but all indications are that today will probably be the main event. I would expect that most (but not all) of the area will pick up 0.5 to 2 inches of rainfall today, with lesser accumulations possible on Friday and Saturday. Although a few intense downpours may briefly produce street flooding, these rains will, by and large, be very much welcome after our summer of heat and drought.

Thursday

Overall rain chances will be about 80 percent today given the favorable environment. Based upon the latest modeling I expect showers and thunderstorms to start developing by mid- to late-morning, with the greatest coverage during the afternoon hours. With mostly cloudy skies and rain cooled air, much of the region probably will record highs today in the mid- to upper-80s. Rain chances will slacken some overnight, but additional showers are possible.

Friday and Saturday

As of this point, both Friday and Saturday look to have similar weather conditions. We can expect partly cloudy skies and perhaps a 50 percent chance of rain both days. In terms of accumulations, both days may see rain totals measured in tenths of an inch, with a few higher isolated totals. Rain chances will persist into the evening and overnight hours. Both days should see highs of around 90 degrees.

Sunday

It now looks like a lesser chance of rain will persist into Sunday, probably something like 30 percent. Skies will be mostly sunny otherwise, with highs of around 90 degrees or a bit higher. Sometime on Sunday a weak front will push offshore, ushering in some slightly drier air into the region. This will effectively end rain chances, and should allow lows on Sunday night to drop into the low 70s for most of the area.

Next week

The slightly drier air should hang around for Monday and Tuesday, leading to some decently pleasant mornings and evenings. Highs will likely top out in the vicinity of the low 90s for most of next week, perhaps reaching the mid-90s toward week’s end. As the humidity returns in full force by around midweek, we should start to see the return of a few clouds and rain chances of perhaps 20 percent each day. This is about how mid-September should feel as we await the true onset of fall in the form of a strong-ish cold front. (For which there is nothing in sight, I’m afraid).

Good morning. For the upcoming period when we expect Houston to see better rain chances, Wednesday afternoon through Saturday, we’re now within the forecast range of high resolution models. This is important, because these models are better able to resolve the convective processes that produce rainfall. Typically, therefore, they tend to provide us with better insight into the timing, duration, and extent of rainfall.

If you recall, in our earlier posts this week, we spoke about accumulations of 0.5 to to 1 inch of rain, but based upon the latest modeling it now appears likely that many locations will receive more than this. Generally, that should be an excellent thing, because so much of the region remains in an exceptional or extreme drought.

So how much rainfall are we talking about? Well, it’s still too early to have great confidence, because our best high resolution models are still only looking out to Friday, not all the way through the high-rainfall chance period. But based upon the latest data, the current expectation is that much of the area will receive 1.5 to 3.0 inches through Saturday.

All of this is being driven by the absence of high pressure, and a weak front drifting toward the area that will help perturb the atmosphere. Our confidence in some of the fine details remains uncertain, but overall the pattern is supportive of widespread, on-and-off rainfall. We cannot rule out some flooding, but conditions are not optimal for very heavy, sustained rainfall, so I don’t expect significant issues on area roadways.

Wednesday

Today should be the last day that the region sees high temperatures in the mid-90s for a little while. Expect highs, generally, in the range of 93 to 97 degrees, with partly sunny skies. Rain chances are low today before the late afternoon and evening hours, at which point the favored locations will be between Interstate 10 and the coast. Rain chances will persist into the overnight hours, albeit with lesser coverage. Winds will be light, generally from the northwest. Lows tonight will drop into the upper 70s.

Thursday and Friday

It still appears that these days will offer the best rain chance for the entire metro area, likely around 70 percent. Skies on both days should be partly to mostly cloudy, and this should help to limit highs to around 90 to 92 degrees. Both days should see widespread, intermittent showers. Winds will be light, from the northeast. Rain chances will be less overnight, but still non-zero.

Saturday and Sunday

The first half of the weekend will see a continued chance of rain, with highs again in the low 90s. However, by Sunday morning we should start to see the influence of a weak front that will bring drier air into the region and largely end our rain chances. Highs on Sunday will probably be in the low 90s, with overnight lows dropping pleasantly into the low 70s.

Next week

With the influx of drier air, we’re likely to see highs in the mid-90s on Monday and Tuesday. However, humidity will be slightly lower, with nights a bit cooler. The front’s influence will dissipate pretty quickly, however. Therefore, most of next week probably will see highs in the low- to mid-90s, with some slight rain chances maybe returning by Wednesday or Thursday. Still no sign of a strong fall cool front yet, I’m afraid. We’re still at least 10 days out from that.

Tropics

The good news is that the Gulf of Mexico is completely quiet, and likely to remain so for at least the next week or 10 days. Wind shear is really ripping out there, and that’s lovely to see in September, especially with sea surface temperatures so warm. Hurricane Lee, however, is increasingly a concern for New England and Nova Scotia. We’ll continue to have full details on Lee, and all the rest of the Atlantic basin, on our sister site The Eyewall.

The region’s drought has steadily worsened this summer, with unrelenting heat and only very isolated to scattered rain showers in July and August. At the start of summer there were virtually no dry or drought conditions anywhere near the greater Houston region. Now half of the area is is an exceptional drought, and the other area is in an extreme drought. (They’re both bad, but exceptional is worse).

While the rains we’re going to receive in the next several days aren’t going to break the drought, they can at least start to put a dent in it. And psychologically, for a lot of us, they’re going to feel oh so good. Beginning Wednesday, and persisting through Saturday, we’re going to see daily rain chances on the order of 40 to 60 percent as a disturbed pattern stalls overhead and helps to generate lift in the atmosphere. Most of the area probably will see, on average, 1 inch of rainfall, but there will be a wide variance in totals. Daytime highs will be cooler with the rainfall.

Tuesday

It probably won’t rain today. Oh, there’s perhaps a 15 percent chance of showers this evening, but for the most part we’re going to be sunny and hot, with highs in the upper 90s. A few far inland areas may touch 100 degrees. Skies will be partly to mostly sunny, with only very light winds. Slight rain chances will continue tonight, with lows in the upper 70s.

Wednesday

This will be another partly to mostly sunny day, but highs are likely to top out in the mid-90s. Rain chances on Wednesday afternoon and evening are probably on the order of 30 to 40 percent. Some stronger thunderstorms will be possible, but for the most part these showers should be fairly light.

Thursday and Friday

These two days will likely carry the best potential for rain, with a healthy 60 percent chance each day. With partly to possibly even mostly cloudy skies, highs likely will top out in the low 90s. (Some locations may actually top out in the upper 80s, if you can believe that). Afternoons will be the most favored time period for showers and thunderstorms, although they will be possible overnight as well.

Saturday and Sunday

The first half of the weekend will offer one more healthy chance of rainfall, with highs in the low 90s. After this time a weak front will be moving toward the area, and this should bring slightly drier air and mostly end the potential for rainfall. So we should be back to mostly sunny skies on Sunday, with highs in the low- to mid-90s. Nighttime temperatures to start next week should be a bit cooler with the drier air. I’ll go with lows around 70 degrees in Houston, but there is definitely some wiggle room to go a little bit cooler or a little bit warmer.

Next week

I’d love to tell you that we’re going to slip even further into fall next week, but it looks like Houston will fall on the periphery of another high pressure system, and this is likely to bump our high temperatures back into the mid-90s for awhile. The worst of summer is over, but alas, summer is not over.

Thanks to a drier airmass this weekend, we’ve seen overnight low temperatures dropping from their extreme highs this summer. Lows this weekend at Bush Intercontinental Airport were 71 and 70 degrees on Saturday and Sunday mornings. This slightly drier air will start to mix out over the next couple of days, leading to a better chance of rain later this week.

Highs will be in the mid- to upper-90s to start the week, but should cool off a bit with the better rain chances toward the end of the week. And another weak front appears to be on the horizon by late weekend that may—just maybe—push daytime highs into the upper 80s for some locations. No promises!

Monday

With light northeasterly winds today, we’re going to see continued sunny skies and highs in the mid- to upper-90s. Due to the light winds, the Texas Commission on Environmental Quality has issued an Ozone Action Day, meaning that atmospheric conditions are expected to be favorable for producing high levels of ozone pollution today. People who are sensitive to this should take precautions such as limiting time outdoors. Low temperatures tonight will be a few degrees warmer, likely in the mid-70s for much of the area. This is still considerably cooler than we’ve experienced for most of the summer.

Tuesday

Another sunny day, a lot like Monday. However as winds become easterly and southeasterly we’ll see a bit more humidity. Expect mostly sunny skies and highs generally in the mid- to upper-90s. Rain chances remain essentially zero.

Wednesday and Thursday

The atmosphere turns more perturbed by mid-week, and with slightly higher atmospheric moisture levels we should start to see better rain chances by Wednesday afternoon or evening. Daily rain chances will be on the order of 40 to 50 percent, probably. Showers most likely will not last super long, but some areas could receive a decent soaking of a few tenths of an inch of rainfall, or more. Daytime highs will depend on the extent of rain and cloud cover, but for the most part expect temperatures in the low- to mid-90s.

Friday

Our rain chances look to peak on Friday, with coverage of perhaps 60 or 70 percent of the area. Look for highs, again, to be in the low- to mid-90s. Accumulations for Saturday look higher for inland areas, perhaps an inch or more, and lesser closer to the coast.

Saturday and Sunday

Some rain chances will linger into Saturday, but for the most part skies should be mostly sunny with highs in the low- to mid-90s. Rain chances should end definitively by Sunday, as another weak front appears likely to push into the area. The extent of this front’s influence remains a bit unclear, but we should at least see some drier and slightly cooler air by Sunday or Monday night.

Next week

Most of next week should see sunny skies, with highs possibly in the upper 80s to start the week, before warming back into the low- to mid-90s.

I’m not ready to declare “Fall Day” yet, as that comes with the season’s first decently strong front, which knocks air temperatures down to 65 degrees or below. And this definitely is not “fall-like” weather. But it is fairly typical for mid-September, and an improvement from a few weeks ago.