Near record warmth Friday as severe storms threaten northern Illinois

 

Temperatures are expected to climb Friday as a strong warm front surges north across Illinois Friday afternoon. Highs during the afternoon are likely to warm into the 60s, possibly reaching 70 degrees (depending on how long clouds and rain last from the morning). 70 is the record high for Rockford which was set in 2000. But the warmth will also come a chance for a couple rounds of thunderstorms, first during the beginning of the day and then again late in the evening.

The first wave will arrive ahead of the warm front and likely remain elevated. What are elevated thunderstorms? They are storms that develop over a stable air mass at the surface. The instability is aloft, rather than near the surface. While these don't pose a high severe risk, elevated storms can produce hail and even some gusty winds. Storms from late Thursday night will move from the Plains into northern Illinois Friday morning. These storms will be moving in ahead of the arrival of the warm front, so the risk for anything severe remains low. The only thing we would need to keep an eye on would be if the front speeds up a little as the storms move out. If that occurs, then there is a chance that a storm or two could become surface based and that would slightly increase the chance for an isolated severe storm. The risk of that happening does remain low, but it is something we'll be keeping an eye on.

The next chance for thunderstorms will arrive Friday night with the main cold front. While the timing isn't overly favorable for severe weather locally plenty of warmth, moisture, and strong winds could lead to a few bursts of stronger wind gusts. This window would occur from roughly 10pm/11pm, to just before 3am/4am.

The Stateline is highlighted under a 'slight risk' for scattered severe storms, with the second wave posing the best chance, but we also have to watch what comes in mid to late morning/early afternoon. In between, temperatures will warm and it may even feel a little muggy for a time through the late afternoon and evening.

Be sure to remain aware of the weather for Friday and be sure to follow the First Warn Weather Team for weather updates!