Dangerous wintry conditions will persist tonight and through Thursday according to the National Weather Service. They have issued a Winter Weather Advisory for the broadcast area in Iowa. Freezing drizzle and rain will mix with snow tonight before changing into snow on Thursday. There will be significant blowing snow possible over northern Iowa on Thursday afternoon and evening. Then the area will get another dose of bitterly cold weather going into Friday. A Wind Chill Advisory or Warning is increasingly likely as that time frame approaches.
As a result of the wintry mix, roads will become slick and snow or ice covered at times, including this evening’s and Friday mornings commute. Frostbite and hypothermia concerns will return late Thursday night and into Friday morning due to the dangerous wind chills and temperatures. They will not fall as low as they were last week however. Forecasters are predicting that this cold snap will also not be as prolonged as last week’s polar vortex that moved through.
The National Weather Service is forecasting between three to four inches of snow in the Worth and Winnebago County areas. The northern half of Hancock County along with the majority of Cerro Gordo County are expected to receive the same. Fairbault County in Minnesota has already fallen under a Blizzard Warning for the evening and into tomorrow. Kossuth County is expected to receive between 2 to 3 inches of snow. Further south, especially in southeastern Iowa, significant accumulations of ice are expected.
A rare event of “thundersnow” is possible in the broadcast area tonight and into the morning. Thundersnow or a thundersnowstorm, is a very unusual thunderstorm event. Snow falls in place of rain and there is a strong upward motion of warmer air inside the cold air of the front moving through the area. Snow storms are different from thunderstorms which cause thunder and lightning because the ground is generally frozen. In a thunderstorm, the ground sends warm water vapor and air up into the clouds which cools and returns back to Earth in the form of rain and gusty winds. However, if there is enough warm air going up in the updraft during a snow storm, lightning followed by thunder will occur. Lightning is generally not seen because the snow generally absorbs the light. Thunder can be heard and is not as absorbed by the snow in the storm. One will notice and increase in the intensity of the snow during the event.
During the snow storm, travel may become extremely dangerous, especially with the strong winds expected to gust above 30 miles per hour at times. Travel is not recommended especially for high profile vehicles in open areas. Stay with KIOW and kiow.com for further weather details. Cancellations can be found on this website at the top of the homepage.