Frost dates in Baltimore, Maryland

NOAA 1991–2020 normals for a 32 °F freeze. Low spots and the edge of town run colder than downtown.

Short answer

The average last spring frost in Baltimore is March 24, and the average first fall frost is November 21, from NOAA's Md Sci Ctr Baltimore station, 1 mile from the middle of Baltimore. 1 year in 10 the last frost comes after April 4, and the first one by November 7. That leaves about 242 frost-free days. Baltimore is in USDA planting zone 8a.

Weather stations around Baltimore

The first row is the date most people in Baltimore go by. The others show how far the dates move across the area.

Station	Last spring frost	First fall frost	Frost-free
Md Sci Ctr Baltimore 1 mi away, 20 ft	March 24 1 in 10 after April 4	November 21 1 in 10 by November 7	242 days
Cylburn 4 mi away, 235 ft	April 2 1 in 10 after April 13	November 7 1 in 10 by October 27	219 days
Baltimore Wash Intl Airport 10 mi away, 156 ft	April 10 1 in 10 after April 25	October 31 1 in 10 by October 17	204 days
Laurel 3 W 21 mi away, 400 ft	April 5 1 in 10 after April 19	November 9 1 in 10 by October 27	218 days
Annapolis Police Brks 22 mi away, 25 ft	March 27 1 in 10 after April 9	November 13 1 in 10 by November 1	231 days

Distances are from the middle of Baltimore as the Census Bureau maps it. The average date is NOAA's 50% date: half of years have a later last frost, or an earlier first one. Plan by the 1-in-10 date if a freeze would cost you plants. The planting zone is the USDA 2023 zone for ZIP code 21202, at the middle of the city.

Your exact ZIP code

Baltimore covers a lot of ground. For the station nearest your own street, and its planting zone, type your ZIP code.

How these dates work

Frost dates come from NOAA's 1991 to 2020 Climate Normals, which work out from each weather station's daily lows how likely the last spring freeze and the first fall freeze (32 °F) are by each date. We use the station nearest the middle of your ZIP code and show its height and distance, since a station on a hill or by a lake can differ from your yard.

The average date is the 50% date: half of years have a freeze after the spring date or before the fall one. The 1-in-10 dates are NOAA's 10% dates, the ones to plan by if a late freeze would cost you plants. Within one yard, cold air pools in low spots while walls and paving hold heat, so some corners freeze before others.

More frost dates

All of Maryland, station by station.

Nearby: Alexandria, VA · Philadelphia, PA · Richmond, VA