The cold air is just start to arrive in the Washington, D.C. metro region, with temperatures in the mid-to-upper 30s across the region after early morning highs in the upper 40s. The next 12 hours, in particular, are going to make for a wild ride, with temperatures and wind chills dropping close to 30 degrees from current levels (and 40+ degrees from this morning).

This chart tells the story.

Temperature forecast 2 p.m. Monday through 1 p.m. Tuesday

* By 9 p.m., temperatures are approaching 20, with wind chills in the single digits
* By midnight, temperatures are into the mid-to-upper teens, with wind chills below zero
* By 7 a.m. Tuesday, temperatures bottom out in the high single digits downtown and wind chills about 10 below
* By Tuesday afternoon, temperatures only rise into the mid-teens with wind chills still hovering around zero.

If you live in colder north and west suburbs, you can subtract 5-10 degrees off of these levels. That means lows Tuesday morning in the low single digits to near zero, and wind chills of 15 to 20 below.


Prince William County schools have already announced they will close Tuesday, and Prince George’s County schools will open two hours late.

This is a two-apple kind of day throughout the region: a good chance of a delay for many schools, with some closures.


 50/50 chance of unscheduled leave policy and/or delay