Excessive Heat Warnings & Heat Advisories are up & expanding north & northeastward as intense, hot upper ridge begins expansion..
Worst of the heat gets in here by Sunday or Monday, but even Saturday will run 93-98.
Heat indices may reach 106-116.
Even next Wednesday, highs may still reach near 100 in some areas.
Other than brief slight relief late next week, heat waves dominate the rest of July.
More sustained relief should arrive in early August (after storms), but another heat wave could occur in mid-August.
Round of storms is likely Wednesday evening to early night.
Entire viewing area is under MARGINAL RISK of severe weather with SLIGHT RISK up to the state line.
Current thinking is that worst of evolving & bowing MCS will make a bit of a right turn, riding the edge of the intense heat of the upper ridge & also ridge the edge of the best instability. MCS will evolve with MCV from severe storms that occur today Wisconsin & Iowa to Missouri.
That is why Illinois has higher severe probabilities than we do at the moment.
However, this could easily expand eastward & we could partially or completely end up in the SLIGHT RISK pending future data coming in his afternoon through tomorrow.
Thursday looks mostly dry other than an isolated storm or two later in the day, followed by potential of some storms Friday AM & late PM with some severe risk.
Some storms on periphery of intense heat are possible Saturday (with some severe risk).
Sunday-Tuesday looks strongly capped & hot as ridge completely takes over.
Storms return late Wednesday & again Thursday of next week. Some severe weather is possible as surface cold front & upper trough approaches.