Nearly a 20 degree rise in temperatures occurred from Wednesday afternoon to Thursday afternoon, bringing highs Thursday into the mid and upper 40s; officially reaching 48 degrees in Rockford. That warmth will continue into Christmas Eve Day, but the day itself will be filled with plenty of cloud cover, drizzle and eventually fog and light showers by Christmas Eve night.
A series of warm fronts passing through the Midwest is behind the late season warm-up, bringing record warmth across the Plains and South heading into the weekend. Locally, we’ll fall short of a record high for Friday, December 24th, but it won’t be by much as temperatures are forecast to reach 51 degrees during the afternoon. The record high for Friday currently sits at 55 degrees, set back only two years ago in 2019. In fact, three consecutive record high temperatures were set that year – the 24th, 25th and 26th. The warmest Christmas Day high ever recorded was only two years ago when the high temperature that afternoon reached a balmy 59 degrees. The forecast high for this Christmas is the mid 40s.
An increase in moisture during the day Friday will lead to more cloud cover, and eventually an increase in drizzle and fog throughout the afternoon. While not the best day to be out and enjoy, there shouldn’t be too many issues for travel, at least early on. The fog may turn a little more dense with a steadier rain during the evening and overnight. This will occur as low pressure moves quickly from the Southwest and across central Illinois. There could even be a few thunderstorms south of I-80 Friday night. Rainfall amounts during that time won’t be much, only adding up to around a quarter of an inch. Higher rainfall totals are expected further south.
Light rain showers will continue into Christmas Day with a drier afternoon to follow. Temperatures near the state line will be close to freezing early on so a few light snowflakes could occur in those locations. Another quick moving low to the north could bring a few more light snow flurries late Saturday evening. Highs on Christmas will reach the mid 40s.