If the forecasters out at Sterling have it right, Central Maryland is looking at the coldest temperatures of the season tonight.
BWI-Marshall could see an overnight low of just 11 degrees by Saturday morning (map). That would beat the low of 16 degrees reached on Dec. 16. The high for Saturday would struggle for 24 degrees as arctic air continues to rush into the region behind Friday morning's exiting snowstorm.
Marylanders out in the western mountains will see lows near or below zero tonight, with wind chills of minus-5 to minus-15 degrees as winds rise to 20 or 30 mph, gusting to 40, forecasters warned. Wind Chill Advisories are posted for western Allegany County.
In Baltimore, local health officials have declared a Code Blue Health Alert through Sunday, extending hours in the city's shelters and sending outreacher workers to check on vulnerable residents.
The cold will stick around for at least the next week, although temperatures will moderate some along the way. Highs at BWI-Marshall Airport won't reach the freezing mark again until Tuesday, if the forecast holds up. Lows will rise out of the teens by Monday night. This is all far colder than the averages for this time of year. The average high for BWI is now 41 degrees; the low is 23.