FrostDateCheck

Washington, DC 20547 Frost Dates

20547, near Washington, DC: the frost window

Zone 8a

The last spring frost here typically falls around 03/29, about 213 days from today. Fall's first freeze usually shows up around 11/08, roughly 224 days after the last spring frost.

Washington sits in USDA Zone 8a (10 to 15°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.

Stretching the season past the first frost

Washington's growing season runs out in roughly 10 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.

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

At roughly 224 frost-free days, Washington places 11,691 of 40,283 ZIP codes in this dataset. Within DC, it ranks 219 of 246.

Learn more

Two guides worth reading on 20547: the frost range, on how to read the range around Washington's dates instead of trusting one, and local microclimates, on what one yard in Washington can differ from the 20547 normal.