A late-winter surge of arctic is air is about to plunge into the Middle-Atlantic cities of Philadelphia, Baltimore, and Washington by this evening. Gusty winds both ahead of the front today, and behind the front tonight, will make it feel even colder. Before the front crosses the area this afternoon, winds will come out of the south and temperatures will rise into the 30s (not bitter cold but still at least 10 degrees below average). The frontal passage will be dry, although a flurry of snow cannot be ruled out.
As we move into the overnight hours, temperatures will plummet into the 20s during the evening and teens during the overnight. By Friday morning, the mercury will be as low as the low to mid 10s to the northwest of Philadelphia, Baltimore, and Washington; the mid to upper 10s in the downtown areas, and the upper 10s to lower 20s closer to Chesapeake Bay. Some outlying areas may fall into the upper single digits. During the day on Friday temperatures will struggle to break into the lower and middle 20s under bright sunshine. Highs may stay closer to 20 in the Philadelphia area, which is quite remarkable considering the higher February sun angle and the fact that average high temperatures in the Middle Atlantic are 45 to 50 degrees for this time of year.
Fortunately, this latest outbreak of arctic air will be brief with temperatures rebounding into the 30s over the weekend. However, computer forecast models are indicating that another surge of arctic air may invade the northeast United States during the first week of March with potentially record-breaking temperatures. The cities above will also have to deal with a powerful late-winter storm that will bring a wide range of precipitation types from Sunday to Tuesday that may end in accumulating snow.
Here are the links to specific weather forecasts for your region of the Middle Atlantic: