Timeline: Here’s when severe storms could hit Chicago area

The Chicago area is once again at risk of severe thunderstorms on Thursday, and the weather is going to change dramatically throughout the day.

According to the latest guidance from the Storm Prediction Center, most of the Chicago area is at an “enhanced” risk of severe storms Thursday, the third of five levels used by the SPC. That area includes the city of Chicago as well as all of northern Indiana and most of the southern and western suburbs.

McHenry and Lake counties, along with the far northern portions of DeKalb, Kane and Cook counties, are at a “slight” risk, the second of those five levels.

Wherever strong-to-severe storms end up firing on Thursday, all manner of threats will be in place, especially large and damaging hail, gusty winds and a chance of tornadoes, some of which could be “strong,” forecasters warn.

So when will the weather be at its worst, and what will happen behind the approaching front? Here’s what to know.

Wednesday Night:

Temperatures are expected to remain pleasant on Wednesday night into Thursday morning, with perhaps a scattered shower or two but no significant precipitation to speak of.

Winds will also be mostly calm, but that will slowly start to change as Thursday dawns.

Thursday Morning:

Most of the morning hours should be clear in the Chicago area, though parts of southern Wisconsin could start to see rain in the late morning hours.

The big unanswered question is just how far north extremely warm temperatures will make it on Thursday, as a mass of cold air is expected to begin to sweep off of Lake Michigan ahead of a cold front that will be moving through the area.

If that warm air can’t make it to the city of Chicago, temperatures will struggle to hit 60 degrees, and in the area the warm air is able to reach readings could soar into the 70s or even the 80s, according to forecast models.

Where that dividing line sets up will be key to determining which areas will be impacted by strong-to-severe storms as the day moves along.

Thursday Afternoon:

The front sweeping south through the area will begin to influence the northern portions of the city and suburbs, with falling temperatures and scattered showers and storms possible, according to the NBC 5 Storm Team.

A few of those storms may be severe, but the main event for the weather will occur in the late afternoon and into the evening.

Thursday Evening:

Thunderstorms will become wider in coverage, and there is some concern that supercell storms could develop, bringing with them the chance for large and damaging hail, gusty winds and even tornadoes.

While the main tornado threat may set up to the south and east of the Chicago area, there is still definitely a chance for some rotation within storms, and residents are urged to be vigilant about that risk.

Also in play is large hail of two inches in diameter or more, which could impact some areas that were hammered earlier this month by severe weather, according to the NBC 5 Storm Team.

As those storms move through the area, temperatures are expected to plunge behind the front, dropping 20-to-30 degrees by midnight according to forecast models.

Friday:

Rain will fully clear out of the area shortly after midnight, but temperatures definitely aren’t expected to rebound, with readings in the 40s and gusty winds making it feel even colder area wide.

Saturday/Sunday:

Fortunately the super-chilly weather won’t last for long, as temperatures are expected to rebound into the 50s on Saturday and then into the upper-50s or perhaps even low-60s by Sunday, with mostly clear skies expected both days.