* WHAT...Very hot daytime temperatures combined with warm overnight lows will produce cumulative heat stress.
* WHERE...Portions of southeast Montana and north central Wyoming.
* WHEN...Until midnight MDT Wednesday Night.
* IMPACTS...Heat related illnesses increase significantly during extreme heat events.
* ADDITIONAL DETAILS...It will be very hot today and Wednesday with high temperatures of 98 to 105. Very warm nighttime temps will provide only limited relief.