The Chicago area broke a 99-year record Tuesday morning, with the mercury hitting 63 degrees.
But forecasters are warning not to get used to it.
Highs on Tuesday reached 63 degrees, shattering the daily record high of 59 degrees for the day set in 1914. According to the National Weather Service, only 33 January days have reached 60 degrees or higher in Chicago the 141 years of recording data.
The last time a 60-degree high was recorded in January was Jan. 7, 2008, when the temperature reached 65 degrees.
Tuesday's record warmth was paired with flood watches for Cook, Will, Benton, Jasper, Lake, Newton, Porter and LaPorte counties through 5 a.m. Wednesday.
Scattered showers and thunderstorms moved through the area Tuesday evening, and up to 3 inches of rain were expected to fall throughout the night.
According to the National Weather Service, the rain will be falling on frozen ground, resulting in near immediate runoff and rapid rises in area streams and rivers.
Flooding was expected to occur in flood-prone or poor drainage areas, with significant rises and flooding on and near area waterways.
Tuesday's warmth and rain is expected to change to snow by early Wednesday afternoon, with temperatures turning sharply colder. Wednesday's high is expected to be in the lower 40s with lows around 13 with 35 mph winds.