It is time for PrairieFest 2018 and along with the good times heating up at the festival, our weather appears to be heating up right along with it. Gradual warming will begin to take place on Thursday before things really heat up for the finale on Sunday. Fest goers will want to prepare for hotter than normal conditions over the weekend.

In addition to heat, humidity will also be on the rise making it feel sticky out there. Thursday’s temperatures look to be seasonable and nothing too extreme, generally around 80 degrees under mostly sunny skies.

Friday’s forecast looks similar but with one potential complicating factor – morning thunderstorms. Some forecast models suggest a decaying complex of storms could move through in the early morning. The skies should clear out for the remainder of the day and the weather should be precip free. Temperatures could be a tricky thing to forecast, however. Cloud debris from these storms could limit greater warming and once again we could see temps around 80. If we do not see storms in the morning, we could warm up to mid/upper 80s. We’ll have to monitor closely.

By Saturday the real heat begins to take shape as a ridge builds and strengthens over the area. Highs around 90 seem a good bet.

Sunday will be the stickiest day of them all as the ridge further strengthens and temperatures could reach the mid 90s. With dewpoints creeping into the mid 70s this could creat heat index values of 100-105 degrees.

Beyond the weekend, Monday will be a similarly hot day as Sunday, before a frontal boundary sags south along with an increased chance for showers and thunderstorms. We should return to more seasonable temperatures by the middle of next week.

Overall it looks like a majority of the next 4 days shall be precipitation free, with plenty of hours to enjoy being outside! We will continue to monitor for any changes in the forecast, especially if thunderstorm chances increase along with the building heat and humidity!

-Adam Lucio – Illinois Storm Chasers