Shivering yet? The entire D.C. area is waking up to extremely cold Monday morning, thanks to a Canadian air mass that has moved into the region.
A freeze warning means sub-freezing temperatures are expected.
The cold will persist Monday: High temperatures will be in the mid to upper 50s in most spots, but may stay in the low 50s to the North and West.
By Tuesday, however, temperatures should be back into the 60s -- and then into the 70s on Wednesday and Thursday.