Your nature year
Williamsport, Pennsylvaniathrough the year
When do frost, green-up and fall color come to Williamsport?
The USA-NPN spring index puts first leaf here around Apr 6 and first bloom around May 5. Frost usually lets go around Apr 25 and comes back around Oct 24, according to the Williamsport 2 weather station (2.8 mi): roughly 182 days without it. Statewide, Pennsylvania's fall color is usually well under way by late October. Head northwest for the closest of the 25 places we follow around Williamsport. The closest place we follow is Little Pine State Park, 19 miles away, for fall foliage, usually well under way by late October (statewide). For wildflowers, the nearest is Catoctin Mountain (113 mi, Apr 1–May 31 (local timing)). Williamsport sits at about 530 feet.
Updated Sep 28. Sources: US Census Bureau, 2024 Gazetteer (places) ↗ (opens in a new tab), US Census Bureau, city and town population estimates, 2024 ↗ (opens in a new tab), NOAA NCEI U.S. Climate Normals 1991–2020 (annual/seasonal) ↗ (opens in a new tab)
Williamsport's year at a glance
- Frost possible
- Frost-free, ~Apr 25 to ~Oct 24
- First leaf ~Apr 6
- First bloom ~May 5
- Fall color under way ~Oct 25 (PA)
- Today
Near Williamsport right now
- Fall color is usually well under way by late October in PennsylvaniaStatewide · USA-NPN volunteer observations, 2020–2025 · not a forecast~4 weeks
- First fall frost usually around Oct 24 · last spring frost around Apr 25NOAA 1991–2020 normals, Williamsport 2 (2.8 mi, 50% dates)~4 weeks
- Fall foliage · Little Pine State Park · 19 miStatewide: usually well under way by late October~3 weeks
Williamsport's nature year
- Cherry blossoms · Baltimore (Fort McHenry)Mar–Apr
- Wildflowers · Catoctin MountainApr–May
- Spring green-upApr
- Last spring frostApr
- Fall color (PA)Oct
- First fall frostOct
Nearby, season by season
Cherry blossoms
- Baltimore (Fort McHenry) · 138 miusually Mar 24–Apr 7~6 months
Fall foliage
- Little Pine State Park · 19 miStatewide: usually well under way by late October~3 weeks
- Hyner View State Park · 31 miStatewide: usually well under way by late October~3 weeks
- Bald Eagle State Park · 35 miStatewide: usually well under way by late October~3 weeks
Wildflowers
- Catoctin Mountain · 113 miLocal timing: Apr 1–May 31~6 months
Snow in Williamsport
Snow usually becomes possible around Nov 25 (our calculation from NOAA's daily snow chances: the first day the chance of 0.1" or more of snow reaches 10%). NOAA's normals at Williamsport 2 (2.8 mi away): 33 inches of snow in an average year, about 9.6 days with 1 inch or more.
NOAA's chance of at least 0.1 inch of snow on each date (one value per week, September to May), averaged over 1991–2020. A typical year, not a forecast.
Frost and green-up
Last spring frost
Apr 25
Average (50% date)
First fall frost
Oct 24
About 182 days without frost between
Spring green-up
Apr 6
First bloom around May 5
Frost: NOAA 1991–2020 climate normals at Williamsport 2 (2.8 mi from Williamsport), the day a 32 °F night is as likely as not. Green-up: the USA-NPN Spring Index, 1991–2020 average at the town.
Questions people ask
When is the first frost in Williamsport?
On average around Oct 24, and the last spring frost around Apr 25: about 182 days without frost between. These are NOAA's 1991–2020 normals at Williamsport 2, 2.8 miles away (the day a 32 °F night is as likely as not).
When does spring green-up reach Williamsport?
The USA-NPN Spring Index puts first leaf around Apr 6 and first bloom around May 5, on average for 1991–2020 at the town.
Where can I see cherry blossoms near Williamsport?
Baltimore (Fort McHenry), 138 miles (usually Mar 24–Apr 7). Distances are straight-line.
Where can I see fall foliage near Williamsport?
Little Pine State Park, 19 miles (statewide: usually well under way by late October); Hyner View State Park, 31 miles (statewide: usually well under way by late October); Bald Eagle State Park, 35 miles (statewide: usually well under way by late October). Distances are straight-line.
When does it start snowing in Williamsport?
Snow usually becomes possible around Nov 25: our calculation from NOAA's daily snow chances: the first day the chance of 0.1" or more of snow reaches 10%, at Williamsport 2. An average year brings 33 inches (NOAA 1991–2020). A typical year, not a forecast.Sources: NOAA NCEI U.S. Climate Normals 1991–2020 (annual/seasonal snowfall) ↗ (opens in a new tab), NOAA NCEI U.S. Climate Normals 1991–2020 (daily snowfall probabilities) ↗ (opens in a new tab)
How we know
US Census Bureau, 2024 Gazetteer (places) (opens in a new tab) (Sep 27) · US Census Bureau, city and town population estimates, 2024 (opens in a new tab) (Sep 27) · NOAA NCEI U.S. Climate Normals 1991–2020 (annual/seasonal) (opens in a new tab) (Sep 27) · USA National Phenology Network, Spring Index 1991–2020 averages (opens in a new tab) (Sep 27) · USA National Phenology Network, colored leaves observations (opens in a new tab) (Sep 28)