* WHAT...Very cold wind chills between 0 degrees to 10 degrees below zero expected.

* WHERE...Portions of central, northeast and northern Maryland, The District of Columbia and central, northern and northwest Virginia.

* WHEN...Until 10 AM EST Thursday.

* IMPACTS...The cold wind chills as low as 10 below zero could result in hypothermia if precautions are not taken. Frostbite and hypothermia will occur if unprotected skin is exposed to these temperatures. Wind chill values can lead to hypothermia with prolonged exposure. Very cold temperatures can lead to hypothermia with prolonged exposure.

* ADDITIONAL DETAILS...The coldest conditions are expected Tuesday night, with widespread wind chills of 5 to 10 degrees below zero. Other nights, wind chills will be between 0 degrees to 5 degrees below zero. During the daytime, wind chills are expected to only reach the low teens.