FrostDateCheck

Baltimore, MD 21240 Frost Dates

Baltimore, MD: when does the frost end?

Zone 7b

Typically, the last spring freeze lands around 04/10, roughly 225 days out. Fall's first freeze usually shows up around 10/31, roughly 204 days after the last spring frost.

Zone 7b (5 to 10°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 Baltimore, not a forecast for this year.

Stretching the season past the first frost

With roughly 9 weeks until Baltimore'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

04/10 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/27 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/25 and only about 1 year in 10 sees frost after that.

Baltimore against the rest of the dataset

About 204 days separate Baltimore's last and first frost, putting it 16,438 of 40,283 ZIP codes nationally. Within MD, it ranks 362 of 583.

Learn more

Before leaning on 21240's figures: zone vs. frost date explains why Zone 7b and Baltimore's frost date answer different questions, while the frost range explains how to read the range around Baltimore's dates instead of trusting one.