Chicago weather: Severe storms to bring tornado threat

CHICAGO - BREAKING UPDATE: A Tornado Watch is officially in effect until 9 p.m. for dozens of counties in Illinois and Indiana. Tap here to read our latest story.

It’s time to be "Weather Ready" over the next 24 hours or so.

Another significant spring storm system will be moving through our area bringing multiple weather hazards. A Wind Advisory is going into effect for our area until tomorrow morning for gusts of 45+. For the majority of our audience that begins tonight. 

The first wave of showers will likely cross the area during the midday hours. It is possible for a thunderstorm during this period, but the main concern for strong storms is later today. 

There will be a large temperature spread across our viewing area. Northern suburbs may spend most of the day in the 40s before a brief surge of 50s arrives during the early evening. Our southern suburbs will likely be much warmer with high as well into the 60s. I think the official high at O’Hare will be close to 60° but most of the day it will be in the 50s.

Chicago severe storms timeline

What we know:

The time of greatest concern for severe thunderstorms will be between roughly 4 p.m. and 8 p.m., though one reliable model is about two hours later with that threat.

All hazards are in play, including tornadoes, some of which might be stronger over our southern viewing area. Damaging straight-line winds will again be the primary hazard with a chance for hail as well. 

Storms will move out of the area, then temperatures will begin a sharp decline as the second half of the storm system moves through our area. 

Future forecast

What's next:

Snow will begin to fall with a slushy inch or two quite likely by daybreak tomorrow. This will likely have some impact during the morning commute. The rest of Thursday will feature clearing skies and chilly temperatures along with a gusty wind. Highs will barely get into the 40s, but should promote rapid melting of the snow.

Friday will be milder with high as well into the 50s. There is a small chance of a brief rain shower Friday night. 

Saturday will be cooler with a mix of clouds and sun and highs in the 40s. 

Our next chance of rain will arrive Sunday and Monday with highs again a few degrees cooler than normal for late March.