State guides · Pennsylvania · Climate by town
Williamsport, PA rainfall, snowfall and frost dates
Thirty-year averages for Williamsport from NOAA’s 1991–2020 U.S. Climate Normals: rain and snow by month, the last and first freeze, the growing season, and a frost check for any date.
Williamsport averages 43.52 in. of precipitation and 35.8 in. of snow a year. The median last spring freeze (32°F) is April 24 and the median first fall freeze is Oct. 23, a growing season of about 180 days. From NOAA’s Williamsport station; checked Nov. 13, 2026.
Is it safe to plant in Williamsport yet?
Dates from January through July check the last spring freeze. Dates from August on check the first fall freeze.
From NOAA’s freeze probabilities for this station. Low spots and valleys can freeze later in spring and earlier in fall than the station.
Williamsport frost dates
| 32°F freeze | 9 in 10 years | 1 in 2 years | 1 in 10 years |
|---|---|---|---|
| Last spring freeze comes after | April 12 | April 24 | May 11 |
| First fall freeze comes before | Nov. 5 | Oct. 23 | Oct. 6 |
Hard freeze (28°F): the median last one in spring is April 12 and the median first one in fall is Nov. 3. The growing season between the median 32°F freezes, April 24 to Oct. 23, runs about 180 days.
Planting tender plants after May 11 means a freeze afterward in only about 1 year in 10. Planting on April 24 leaves even odds. For lawn seeding windows, see our Pennsylvania grass seed guide.
Williamsport rain and snow by month
| Month | Precipitation (in.) | Snow (in.) | Avg high (°F) | Avg low (°F) |
|---|---|---|---|---|
| January | 2.96 | 9.7 | 35.3 | 20.1 |
| February | 2.31 | 9.3 | 38.7 | 21.5 |
| March | 3.13 | 7.3 | 48.4 | 29.0 |
| April | 3.62 | 0.8 | 61.7 | 39.0 |
| May | 3.86 | 0.0 | 72.4 | 49.1 |
| June | 3.85 | 0.0 | 80.5 | 58.3 |
| July | 4.64 | 0.0 | 84.8 | 62.7 |
| August | 4.17 | 0.0 | 82.7 | 61.2 |
| September | 4.76 | 0.0 | 75.2 | 54.1 |
| October | 3.70 | 0.1 | 63.1 | 42.8 |
| November | 3.25 | 1.7 | 50.6 | 33.2 |
| December | 3.27 | 6.9 | 39.7 | 25.8 |
| Year | 43.52 | 35.8 | Average 51.2°F | |
Precipitation is rain plus the water in melted snow and ice. Snow is the depth of new snowfall. Monthly figures are NOAA’s normals and may not add exactly to the yearly totals because of rounding.
- Wettest month: September, 4.76 in. Driest: February, 2.31 in.
- Snowiest month: January, 9.7 in. Months averaging 1 in. or more: November through March. December through February bring about 72% of the year’s snow.
- Average lows at or below 32°F: December through March.
- Coldest nights: January, average low 20.1°F. Warmest days: July, average high 84.8°F.
Planning outdoor work in Williamsport
Average lows sit at or below freezing from December through March, so plan base work, planting and seeding around the frost dates above. Frost depth and ground snow load for footings and roofs are set by your town; our design criteria by ZIP tool shows who sets them for your address. For planting beds, start with a soil test.
Towns near Williamsport
| Town | Miles | Precip. (in.) | Snow (in.) | Median last freeze | Median first freeze |
|---|---|---|---|---|---|
| Lewisburg | 21 | 43.88 | 28.8 | April 26 | Oct. 20 |
| Laporte | 25 | 53.27 | 69.7 | May 6 | Oct. 7 |
| Lock Haven | 28 | 41.72 | 29.6 | April 30 | Oct. 20 |
| Sunbury | 28 | 43.69 | 28.6 | April 30 | Oct. 13 |
| Canton | 28 | 41.19 | 42.1 | May 16 | Oct. 2 |
| Benton | 30 | 48.42 | 46.0 | May 4 | Oct. 11 |
Miles are straight-line distances between NOAA stations. See every town on our Pennsylvania rainfall and snowfall by town chart.
Questions
How much snow does Williamsport, PA get a year?
Williamsport averages 35.8 in. of snow a year, per NOAA’s 1991–2020 normals for its Williamsport station. The snowiest month is January, at 9.7 in.
How much rain does Williamsport, PA get a year?
Williamsport averages 43.52 in. of precipitation a year, counting rain and melted snow. The wettest month is September, at 4.76 in.
When is the last frost in Williamsport, PA?
The median last 32°F freeze in Williamsport is April 24. In 1 year in 10 it comes after May 11, and in 9 years in 10 after April 12.
When is the first frost in Williamsport, PA?
The median first 32°F freeze in Williamsport is Oct. 23. In 1 year in 10 it comes before Oct. 6, and in 9 years in 10 before Nov. 5.
How long is the growing season in Williamsport?
About 180 days between the median last and first 32°F freezes, April 24 to Oct. 23.
What is the coldest month in Williamsport?
January, with an average low of 20.1°F and an average high of 35.3°F.
About this data
Station: NOAA’s Williamsport station (GHCN USW00014778), elevation 520 ft, 41.243° N, 76.922° W. These are NOAA’s 1991–2020 U.S. Climate Normals, 30-year averages that NOAA recomputes every 10 years. NOAA rates this station’s precipitation normals standard, its snow normals standard and its temperature and freeze normals standard. Standard means at least 24 years of data, with missing months filled from nearby stations.
Your yard can differ from the station. Elevation, valleys and hillsides change how much snow falls and when the first and last freezes come.
Sources: NOAA NCEI, U.S. Climate Normals; annual and seasonal normals for USW00014778; monthly normals for USW00014778; NOAA normals file documentation. Checked Nov. 13, 2026.
Muthler Landscaping & Construction · Lock Haven, PA
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We build patios, retaining walls and landscapes around Lock Haven, Williamsport and State College, and we plan the work around the season.
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Muthler Landscaping & Construction LLC · 913 Bellefonte Ave, Lock Haven, PA 17745 · (570) 397-9800 · PA HIC #PA212584. Climate data from NOAA; not a forecast.
Using this guide? Link to it or cite it. It's free to use with a link back, and we keep it updated against official sources.
Cite as: Muthler Landscaping & Construction, “Williamsport, PA Rainfall, Snowfall and Frost Dates,” https://muthlerlandscaping.com/state-guides/pennsylvania/climate/williamsport/ (last checked November 13, 2026).
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