NORTH TEXAS (CBSDFW.COM) – The cold temperatures are already impacting COVID-19 vaccination clinics in North Texas.

Denton County canceled its second-dose clinic scheduled for Thursday, Feb. 11 at Texas Motor Speedway.

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“We do not want to bring our residents out on icy roads or have our crews and volunteers working in below-freezing weather,” Denton County Judge Andy Eads said in a news release.

Those originally expecting to be vaccinated on Thursday, will be scheduled for the afternoon of Friday, Feb. 12.

On Friday, Denton County Public Health plans to administer approximately 3,000 second doses of Moderna’s COVID-19 vaccine to those due the previous day, as well as 4,500 first doses of Pfizer’s COVID-19 vaccine.

Dallas County had to delay its transition to a full drive-thru operation at Fair Park because of the weather, causing long lines Tuesday, Feb. 9.

“Today is another very frustrating day for everyone involved,” said Dallas County Judge Clay Jenkins.

Since the drive-thru vaccine hub failed to open any lanes, hundreds of senior citizens were forced to wait in car lines for hours to get inside.

Judge Jenkins said it’s difficult to keep the vaccine at the right temperature when it’s sitting outside in the cold weather.

“The vaccine lays on tables between where the cars are,” he said. “If it’s 45 degrees, you don’t have to worry, but if it’s under 40 degrees then that is a problem for the vaccine.”

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The county needed generators to run heaters inside the tents, but there was a delay in getting them.

The new plan is to open up the drive-thru vaccinations Wednesday, Feb. 10 at noon.

Vaccination efforts continued Tuesday at six hubs in Collin County.

Collin County Judge Chris Hill says they’re monitoring the forecast closely right now.

“We’ll be working with our Collin County officials to make a decision if we need to go ahead and postpone any of our appointments later in the week,” said Judge Hill.

Sites in Tarrant County will stay open, even if some people have to wait in line in the cold.

“The reason we’re keeping them open is there is a high interest and there’s a lot of people coming due for their second doses,” said Tarrant County Public Health Director Vinny Taneja. “So if we close the sites, they kind of get backed up and then other people are due for multiple doses and it just becomes too hard to get out of it.”

The county has put up some tents over spots where people line up outside and purchased outdoor heaters.

At some sites, only second-dose people will receive appointments the rest of the week. The county may also limit some of the hours during this cold snap as well – fewer early mornings and later evenings.

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Tarrant County Public Health understands some people might not come out if the weather is bad, but they’re asking them to keep their appointments if they can.

Caroline Vandergriff