Multiple Rounds of Severe Weather Expected to Arrive on Father's Day

Father's Day Preview:

Tomorrow not only marks the first day of Astronomical Summer, but also the day in which we celebrate the amazing dads across the world. While you may have plans for Father's Day, I ask you to please have multiple ways to receive watches and warnings. Father's Day may start off quiet, but clouds are expected to increase, leading to the potential for two rounds of severe thunderstorms. 

All Modes Possible:

Earlier this afternoon, the Storm Prediction Center upgraded a portion of the Stateline, mainly the areas south of highway 20, to an enhanced risk (level 3 of 5) for severe weather. The remained of the region, mainly areas north and west of the Rockford area, currently remain under a Slight Risk. A system moving in from the west will help initiate two rounds of thunderstorms. 

The first being with a lifting warm front which looks to bring impacts to our area late in the morning into mid-afternoon, mainly between 11AM-3PM. This round is the one where we'll have to see if they can sustain themselves as they approach the Stateline. If they remain strong enough, damaging winds and large hail will be the biggest threats, with an isolated tornado or two possible (mainly to the south of the viewing area. 

The second round is the one we really need to keep our eyes on, as this one may bring more of a punch to it as it slides through. The main time-frame for this set of severe thunderstorms looks to be late in the afternoon into the late evening hours, so between 4PM to 11PM. A few outflow boundaries, that were left behind by the first round of storms, will interact with the associated cold front, allowing more severe thunderstorms to develop. These storms will have the potential for all modes of severe weather, including damaging winds up to 60-70 mph, hail stones up to 2 inches in diameter, and a few tornadoes. 

Turning More Fall-Like:

Once the cold front is finished passing through overnight Sunday, a more fall-like weather pattern will filter in for the start of the work week. I mean, we're talking highs falling from the upper 80s today to the low 70s by Tuesday. When we are talking about 70s in June this year, we have yet to observe a high in the 70s. So, it's going to feel much more comfortable and non-summer-like for the first week of Astronomical summer.