Houston's heat streak is nearing a milestone. Is relief finally coming?

Another day of 100-degree heat could put Houston on the verge of one of its longest streaks of triple-digit temperatures on record.

Houston has recorded six days with highs of at least 100 degrees this summer, including five since last Thursday. With more triple-digit heat expected through Thursday, the city could string together enough consecutive 100-degree days to rank among the 10 longest such streaks on record. But a pattern change could soon turn down the atmospheric thermostat, with more clouds and rain chances returning to Southeast Texas.

The heat dome of high atmospheric pressure over the southern Plains is not ready to loosen its grip over Texas just yet.

It will remain in place through Wednesday, keeping skies mostly sunny and rain chances low. A few clouds may drift in from the north and east, possibly knocking a couple of degrees off peak daytime temperatures. That is hardly a true escape hatch, with Houston temps still reaching 100 degrees, and some spots northwest of the city climbing even higher.

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Closer to the coast, temperatures should top out in the lower to mid-90s. That may look better on the thermometer, but the combination of heat and high dew point temperatures (an indicator of air saturated with water vapor) will still make the outdoor air uncomfortable.

Outdoor workers, high school athletes and marching band members alike should build in plenty of breaks, drink water regularly and avoid the hottest part of the afternoon when possible. 

Thursday into Friday, the weather pattern finally begins to shift as the ridge of high pressure drifts westward.

That would leave Southeast Texas between the ridge to the west and lower pressure to the east. Rain chances will increase late Thursday night and into the weekend as daytime heating and daily sea breezes trigger scattered showers and thunderstorms. However, rain will not fall everywhere.

Increasingly brown lawns likely won't turn green anytime soon, though. One neighborhood could receive a downpour while another stays dry. Any storm could briefly lower temperatures, but the rain will not erase the summer heat.

For those looking forward to more typical summertime weather, which is still unmistakably hot in Houston in late August, this weekend is for you.

More clouds and rain should keep weekend highs in the mid-90s across most of the Houston area, with highs landing somewhere between 94 and 97 degrees. That would be a noticeable change from the triple-digit heat expected across parts of the area through Wednesday.

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It will still feel hot, especially when the sun breaks through between storms. Afternoon heat index values could remain in the triple digits, and overnight temperatures will continue to offer limited relief.

Still, the combination of lower afternoon temperatures, more clouds and higher rain chances should take the edge off of our recent heat by the weekend. A more substantial break from the heat will depend on how widespread the showers and thunderstorms become.

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This article originally published at Houston's heat streak is nearing a milestone. Is relief finally coming?.