A sizzling end to September, with probably at least a week to go before a meaningful front

In brief: Summer is not over. In today’s post we explain why the end of September has been very hot, and why that’s not going to change much this week. We’ll also take a look at the weekend forecast, when there are a lot of outdoor events in the metro area. Finally, could we see a real front next week?

Wake me up when September ends

Fifteen of the last sixteen days in September have recorded high temperatures of 90 degrees or higher. (On the single day that did not, the high reached 89 degrees). This has occurred despite a front coming through a couple of days ago.

Why has the daytime heat persisted? Partly because our early fall fronts tend to bring drier air, but not much colder air. So our days remain warm because drier air heats up more efficiently. The primary benefit of the front, however, is that it has taken about 10 degrees out of nighttime temperatures, which has been nice.

October is not going to bring immediate relief, but as our air modifies somewhat this week with higher humidity, we’ll see slightly cooler days by around Wednesday, and correspondingly warmer nights in the mid-70s. Later this month we can almost certainly count on more emphatic fronts to bring cooler daytime weather.

Monday

High temperatures today should, once again, reach the mid-90s for much of the metro area away from the coast (where highs will be a few degrees cooler). Skies will be sunny, with almost nary a cloud in the sky. Winds will be light, generally from the northeast. With dewpoints mostly in the 60s, the air won’t exactly feel dry, but it won’t be Houston-humid either. Lows tonight will drop into the low 70s for most locations.

Tuesday

A similar day to Monday, albeit with possibly a few more clouds in the sky.

Wednesday and Thursday

Expect more sunshine, with daytime highs generally in the low-90s, and nighttime temperatures in the mid-70s. Really, there’s not much more to say.

Friday, Saturday, and Sunday

So there are a lot of fairly big events in Houston this weekend, and a lot of eyes on the weather. On Saturday there’s the Komen Houston Race for the Cure in Sam Houston Park, as well as the Southern Smoke Festival in Discovery Green. What I can tell you right now is a forecast for what will probably happen, but not a forecast for what will absolutely happen.

Our atmospheric pattern will become somewhat more upset by Friday, opening the door to a few passing disturbances. Effectively, this means that we’re likely to see daily rain chances on the order of 20 to 30 percent during the Friday, Saturday, and Sunday period. Chances will be low- to non-existent for areas inland of Interstate 10, and at the higher end along the coast.

Friday and Saturday are likely to see partly sunny skies, whereas Sunday looks to be mostly sunny at this point. High temperatures will probably range from the upper-80s to lower-90s. The risk to the forecast is that the atmospheric disturbances are a little more pronounced than expected, leading to more widespread rain. But at this point the most likely outcome is a fairly warm, mostly rain-free early October weekend that feels more like late summer than early fall.

Next week

There is a fairly decent signal in the global models for a decent front to arrive on Monday or Tuesday of next week, but since I’m not yet certain on its passage I don’t want to give anyone false hopes. Needless to say, next week’s weather in Houston will be determined by whether said front makes it all the way through Houston.

Tropics

We’ve had lots of questions about the tropical blob in forecast maps from the National Hurricane Center. Yes, we’re continuing to keep tabs on it. No, there still is not any indication that an organized tropical system is likely to directly impact the Texas coast over the next week or 10 days. For more information, check out our post from Sunday.