(2:00PM - 8/6/18) A brief update on the severe weather potential across portions of the state today...
In the wake of early day scattered showers and thunderstorms across portions of Northern and Central Illinois, areas of clearing are occurring, which is allowing for some destabilization. By mid-afternoon an environment should be in place featuring moderate to high instability levels, ample shear and good moisture.
As a disturbance moves in from the west, scattered thunderstorms are expected to develop this afternoon across portions of Western Illinois. This activity will pose a severe risk as it pushes eastward across portions of Northern and much of Central Illinois. Damaging winds and hail will be the biggest threats, though and isolated tornado can’t be ruled out. It appears there may be an area of where the severe threat is the highest, in and around a box from Peoria to Springfield to Champaign to Kankakee. Across this area some significant severe may occur. This is represented by the orange area on our TAM map below. While this scenario is not fully likely, it is possible given the environment in place, and worth a mention.
The severe threat will greatly diminish by early tonight, with only an isolated severe threat overnight with general showers and thunderstorms across portions of Central and Southern Illinois
(4:15PM - 8/3/18) After more seasonal temperatures to end July and begin August, hot temperatures are once again making a return the next several days across the state...
Another mini-heat wave is settling in across portions of the region, and will be affecting the state today through Monday. Ridging ahead of an incoming series of disturbances is transporting hotter temps into the area from the Plains. This will lead to high temps into the 90's for much of the state the next several days.
Things have started today with high temps around and into the low 90's across portions of West-Central and Southern Illinois. High temps on Saturday and Sunday will likely be around and into the low 90's for much of the state...With mid 90's likely for portions of Western and Southwest Illinois, closer to the Illinois/Missouri and Illinois/Iowa borders, as well as the Chicago, St. Louis and Quad City metro areas. High temps Monday will likely be around and into the low 90's once again for much of the state, with mid-90's possible for portions of Western and Southwest Illinois. Low temps across the state during the period will range from the mid 60's to low 70's, with mid 70's possible in Chicago and St. Louis.
The good news is unlike all of the other heat waves this summer, this one will lack high dew points. This means humidity and heat indices will be held in check, and will not be too much higher than the actual temperature is.
There is the potential for some cloud debris each day, and thunderstorm potential across Northern Illinois on Monday, which could temper the heat for some areas.