Baltimore, MD 21279 Frost Dates
Baltimore, MD: when does the frost end?
Around 03/24 is the usual last spring frost, about 208 days away. Fall's first freeze usually shows up around 11/21, roughly 244 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 Baltimore, not a forecast for this year.
Stretching the season past the first frost
With roughly 12 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
03/24 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/08 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/04 and only about 1 year in 10 sees frost after that.
Baltimore against the rest of the dataset
About 244 days separate Baltimore's last and first frost, putting it 8,179 of 40,283 ZIP codes nationally. Within MD, it ranks 48 of 583.
Learn more
Before leaning on 21279's figures: local microclimates explains what one yard in Baltimore can differ from the 21279 normal, while zone vs. frost date explains why Zone 8a and Baltimore's frost date answer different questions.