Washington, DC 20318 Frost Dates
Washington, DC: when does the frost end?
Typically, the last spring freeze lands around 03/29, roughly 213 days out. Fall's first freeze usually shows up around 11/08, roughly 224 days after the last spring frost.
Zone 8a (10 to 15°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Washington, not a forecast for this year.
Stretching the season past the first frost
With roughly 10 weeks until Washington's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
How much risk comes with planting early here
03/29 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/15 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/11 and only about 1 year in 10 sees frost after that.
Washington against the rest of the dataset
About 224 days separate Washington's last and first frost, putting it 11,618 of 40,283 ZIP codes nationally. Within DC, it ranks 146 of 246.
Learn more
Before leaning on 20318's figures: zone vs. frost date explains why Zone 8a and Washington's frost date answer different questions, while the frost range explains how to read the range around Washington's dates instead of trusting one.