Fort Worth, Texas,
10:04 AM

Why am I getting bit by a mosquito in December?

An entomologist explains mosquitoes in the winter

You spent the weekend outside playing with your kids or hanging up Christmas lights.

Then you walk inside, feel your arm itching and see the familiar red bumps on your arms. Mosquitoes! In December?

Why are we still seeing mosquitoes three weeks from Christmas?

For the answer, we asked Michael Merchant, Ph.D., a professor and Extension Urban Entomologist at Texas A&M University.

Merchant noticed mosquitoes over the weekend while out in the garden. But he wasn’t too surprised. After all, understanding pest management and insects is something he’s been an expert at for nearly 30 years.

“When the temperature drops below about 55 degrees, mosquitoes stop flying,” Merchant said. “We’ve already seen a major decline in mosquitoes, but we are still seeing a few of the hardier folks persisting.”

Mosquitoes don’t all die off during cold weather, they often just hide in protected spots to avoid freezing.

Mosquitoes are cold-blooded and like temperatures best in the 80s or warmer. Once the temperature drops below 55, they go away – or at least stop moving around as much. Some mosquitoes find holes or places inside to hide in until warmer weather. Others lay their eggs before the freezing weather and then die. The eggs then hatch in warmer winter.

But the risk isn’t over entirely. Merchant said it’s not unusual to see a few West Nile Cases in the Dallas/Fort Worth area into December, and this year’s warm weather has kept the insects around longer than usual.

The last bites of the year may even occur indoors. “A few mosquitoes always make their way indoors, often coming in from your doorways,” Merchant said. “Mosquitoes often hide in protected home entryways to get away from the cold.” From there it’s a short flight inside when the doors open and close.

Merchant suggests sweeping and vacuuming the upper part of your doors and around the doorway, as well as applying insecticides.

“For most of us, the threat of mosquitoes is almost over,” Merchant said. “Hopefully, by next week we will have a blast of cold weather and we won’t see them for a while.

For more information

To learn more on mosquito control around the home, Michael Merchant's website:

  • Mosquito Safari Website. Go on a mosquito safari with this interactive AgriLife website. Mosquito Safari takes you on a walk through both urban and semi-rural landscapes to learn more about mosquito risks, biology and control options.
  • Mosquito videos. Learn more about practical ways to make your home and landscape safer from mosquitoes, and see mosquito larvae breeding in a backyard setting.
Comments 1 - 6 (6)
Thank you for your message. It will be posted after approval.
Felipe Ibarra
We just caught two adult mosquitoes inside the house a few minutes ago (Jan.10, 2022), while it is -17o Celsius outdoors, in a location an hour North of Toronto, Canada. We do not understand how it is possible! I did my undergrad in Biology, so I can assure you that these are mosquitoes, not any other insect.
So I am in utah, west valley is it normal and do u know what I can do to stop getting bites from mosquitoes?
lady with a computer
thought they were mosquito bites but I actually had bed bugs. how fun.
Shawn black
Today the temperature was 66 in wichita falls texas. Although the temperature was 66 and I do live in texas, I was in the kitchen washing dishes and noticed a large size mosquito flying around. I was shocked not only time time of year but how big this mosquito was. I instantly killed it without touching it. Should I be worried about more mosquitoes and the size of the mosquitos ? Today is January 25 2020.
Thanks for this info. I've been bitten over a dozen times since Halloween. I think there's a mosquito in the house, or perhaps hiding under my deck just outside the back door. I thought I was losing my mind getting all these bites in the "winter".
hi last night while in bed half a sleep i was sure i could hear a hig pitch buzzing like a mosquito, any way i went to sleep and when i woke this morning i had a large bite on my hand, i have had mozzy bites before and this is one, it his huge and very painfull,. i did not think it possible to get bites in december, i am in england doncaster yorkshire, at the moment it is snowing,,, kind regards bernadette