October 16, 2026 – Washington Co., Wi – Neighbors across Washington County and surrounding communities are bracing for freezing temperatures overnight Friday, and the cold snap could bring some relief for whitetail deer suffering from epizootic hemorrhagic disease (EHD).
The National Weather Service has issued a freeze warning from 1 a.m. to 9 a.m. Saturday, with temperatures expected to drop as low as 28 degrees in portions of east central, south central and southeastern Wisconsin.
While the cold could damage gardens, flowers and other sensitive vegetation, it may also help slow the spread of EHD, a disease that has killed hundreds of deer in parts of Washington County.
EHD is transmitted to deer through the bites of infected biting midges, tiny insects often called no-see-ums. Freezing temperatures kill off active midges and can help bring the seasonal transmission cycle to an end. However, a single frost does not guarantee that all midges are gone, and the timing and severity of the freeze can affect how quickly their activity declines.
According to the DNR the Washington County area was hit the hardest by EHD with over 1,300 deer reported sick or dead deer found with signs consistent with EHD during the Summer/Fall 2026 outbreak. However local hunters and land owners have indicated the number of deer affected is possibly 10 times what the DNR is reporting.
According to the DNR, “death rates can be much higher, as deer populations have limited previous exposure to the virus and high-density deer herds may have higher mortality rates.”
The National Weather Service advises residents to protect tender plants and take precautions against damage to unprotected outdoor plumbing.
For residents who have watched the EHD outbreak take a toll on the local deer herd, the arrival of colder weather offers hope that the biting insects responsible for spreading the disease will soon disappear for the season.
