To Houston’s list of Official Seasons — Summer, Not Summer — we may be inclined to add another come Thursday. Emphatically Not Summer.

An Arctic blast strong enough to make even liberals denounce Al Gore is expected to race through Southeast Texas late tonight and send temperatures plummeting. The National Weather Service warns of a slight chance of snow or sleet Thursday morning.

Talk about your inconvenient truths. The sudden burst of weather so cold that diehard Yankees would recognize it as winter had officials warning of the need to protect exposed water pipes, outdoor plants and pets. Fire marshals warned of the dangers of space heaters. Harris County’s emergency management department warned of the potential for carbon monoxide poisoning.

At the heart of the warnings was the prediction of low temperatures in the low-to-mid 20s for Thursday, Friday and Saturday nights. The high Thursday morning could creep into the low 40s, but Friday was predicted to be about 10 degrees colder, with a wind chill making it feel like the 20s or worse.

Many stores late Tuesday had already reported running out of space heaters and insulated cloth for covering plants. Foam insulation for pipes also flew off the shelves as cold-weather supplies were starting to dwindle.

“I was here when it got this cold 14 years ago,” said Rick LeBlanc of Aldine after purchasing the worm-like pipe insulation at a home improvement store. “A lot of peoples’ pipes burst back then. I want to be prepared.”

Late-arriving customers sometimes found themselves out of luck in the hunt for space heaters and landscape cloths.

“I’m taking calls about heaters, but most everybody like us is sold out of them and the plant covers,” said Daryl Duke, assistant manager of a Home Depot near Kingwood, where temperatures could drop even lower than central Houston and coastal areas. “I’m hoping I can get some more from our warehouse. But there’s no guarantee.”

Kingwood Garden Center owner Bob Robertson checked with several stores as well as nursery distributors and could not locate any plant covers. He advised against using plastic alone, which has little insulating value and does not allow plants to breathe. Better to use a bed sheet.

This year’s cold winter is likely attributable to El Nino, a natural warming of sea surface temperatures in the tropical Pacific Ocean that tends to cause Texas winters to be cooler and wetter than normal. Scientists also note that a similar pattern of atmospheric pressure in the Arctic, known as the Arctic Oscillation, has plunged this winter, allowing more cold air to reach further south into the United States.

Schools on alert

Starting Thursday, Houston can expect temperatures to run between 20 and 30 degrees below normal levels for January. Weather Service forecasters in the Houston/Galveston office said the mercury will nosedive in the front’s wake late in the day.

Local school district officials are among those paying close attention to the forecasts over the next few days. In the Houston Independent School District, heaters are to be left on overnight to ensure campuses were “toasty warm” for children Thursday morning, said spokesman Norm Uhl. And throughout the cold spell, he said, head custodians will report to school an hour early to check that the heating systems are working properly.

In the event of freezing precipitation, school district leaders will turn their attention to the roads. Transportation supervisors will wake up early, test-drive bus routes and determine if they’re safe.

“If it’s safe to get to school, we will have school,” said Kelli Durham, spokeswoman for Cy-Fair ISD, which buses about 68,000 students daily. This cold snap will likely not set any records, but this should be the most significant chill since 1996, when temperatures fell to 19 degrees.

That’s about the temperature threshold that engineers say poses a significant threat to unprotected pipes outside and in attics. At around 20 degrees, the Institute for Business and Home Safety says, water in pipes freezes, and pressure between the blockage and a closed faucet can cause the pipe to rupture.

Wrap them up

Ron Bevins, operations manager for Abacus Plumbing, advised homeowners who have exposed water pipes to wrap them up.

“If it’s a water line and it’s exposed, it needs to be insulated,” Bevins said. “You can use a towel and duct tape in a pinch. A good old fashioned cotton towel has a lot of insulation to it, or you can buy a hose bib frostproof cover.”

Homeowners also should disconnect any hoses from outside faucets, Bevins said. As for the old technique of leaving a faucet running, he said that is of minimal value and should only be done by those who will be leaving their home and turning off the furnace, or those who have uninsulated pipes exposed to the wind in the crawl space of a pier-and-beam foundation.


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