Around the District, the average last freeze is in late March, while it holds off until mid-April in our colder suburbs west and north. Last freeze is moving upAround the District, the date of the final freeze averages March 24, and it’s a similar story down the Potomac River into parts of Southern Maryland. Dulles’s final freeze has moved forward 10 days since the 1960s. As recently as 2013, Dulles even saw a final freeze in mid-May. 70s are springing sooner, and bringing out the pollenBetween March 9 and 12, the District saw 70-degree days, which kicked early-season tree pollen counts to record levels.

Source: Washington Post March 19, 2021 16:50 UTC