* WHAT...Dangerously hot conditions with heat index values up to 105. * WHERE...Portions of central, north central, northwest, and west central Minnesota and southeast North Dakota. * WHEN...Until 10 PM CDT Tuesday. * IMPACTS...Heat related illnesses increase significantly during extreme heat and high humidity events. * ADDITIONAL DETAILS...Overnight relief tonight into Tuesday morning will be minimal, with overnight low temperatures remaining in the low to mid 70s along with high humidity.