Extreme Heat Warning

* WHAT...Dangerously hot conditions with heat index values up to 105 to 108 expected.

* WHERE...Portions of north central Maryland, northwest Virginia, and eastern and panhandle West Virginia.

* WHEN...From 10 AM this morning to 8 PM EDT this evening.

* IMPACTS...Heat related illnesses increase significantly during extreme heat and high humidity events.

* ADDITIONAL DETAILS...Early morning low temperatures in the 70s combined with oppressive humidity will result in little to no overnight relief. Prolonged excessive heat may impact power, water, and transportation systems. Heat index values of 95 to 100 are possible again Sunday afternoon.