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Frost dates for Harrisburg, Pennsylvania

In a typical year, Harrisburg’s last spring frost lands around Apr 15 and the first fall frost around Oct 23, a growing season of about 191 days. These are odds drawn from 30-year NOAA climate normals, not a promise. USDA zone 7a.

Right now the typical frost season has arrived; planting waits for spring.

Last spring frost and first fall frost odds for Harrisburg, Pennsylvania
OddsLast spring frostFirst fall frost
10 percentApr 1Oct 7
50 percentApr 15Oct 23
90 percentMay 2Nov 7

A 10 percent year is an early year, a 90 percent year a late one. Frost-sensitive planting usually waits for the 90 percent side of the last-frost band.

Soil in Harrisburg is typically around 52°F at 4 inches this time of year, estimated from the last two weeks of normal air temperatures.

See what is plantable in your ZIP with the what-to-plant lookup.

Common questions

When is the last frost in Harrisburg, Pennsylvania?

Harrisburg’s last spring frost falls around April 15 in a typical year. One year in ten it is done by April 1, and one year in ten frost holds on until May 2. Frost-sensitive planting usually waits for the late side of that band.

When is the first fall frost in Harrisburg?

The first fall frost arrives around October 23 in a typical year, as early as October 7 in an early year and as late as November 7 in a late one.

How long is the growing season in Harrisburg?

About 191 days, counted between the typical last spring frost and the typical first fall frost.

What USDA zone is Harrisburg in?

Harrisburg is in USDA hardiness zone 7a under the 2023 USDA Plant Hardiness Zone Map.

Dates come from 30-year NOAA climate normals for the nearest reporting station. They describe odds, not a forecast.

Nearby cities

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