South Williamsport, PA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for South Williamsport, a borough in Lycoming County, Pennsylvania.
Today
72°F
Patchy Fog then Mostly Sunny
Patchy fog before 9am. Mostly sunny, with a high near 72. Southeast wind 1 to 9 mph.
7-day forecast for South Williamsport
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 72°F | Patchy Fog then Mostly Sunny | 1 to 9 mph SE | 1% |
| Tonight | 58°F | Mostly Cloudy then Light Rain | 8 mph SE | 92% |
| Thursday | 72°F | Light Rain | 3 to 8 mph S | 95% |
| Thursday Night | 49°F | Chance Light Rain then Mostly Cloudy | 2 mph W | 25% |
| Friday | 66°F | Partly Sunny | 2 mph S | 13% |
| Friday Night | 45°F | Partly Cloudy | 0 to 5 mph NW | 13% |
| Saturday | 58°F | Chance Light Rain | 5 to 10 mph W | 34% |
| Saturday Night | 39°F | Chance Light Rain | 12 mph W | 34% |
| Sunday | 57°F | Partly Sunny | 10 mph W | 7% |
| Sunday Night | 36°F | Partly Cloudy | 8 mph W | 7% |
| Monday | 57°F | Mostly Sunny | 8 to 14 mph W | 13% |
| Monday Night | 34°F | Partly Cloudy | 3 to 7 mph W | 13% |
| Tuesday | 61°F | Mostly Sunny | 3 to 12 mph W | 6% |
| Tuesday Night | 34°F | Partly Cloudy | 7 mph W | 7% |
Forecast source: National Weather Service (api.weather.gov) for South Williamsport (41.229, -77.000). Updated through the day.
Growing snapshot for South Williamsport
Last spring frost
Apr 25
First fall frost
Oct 24
Growing season
181 days
Hardiness zone
6b
More local growing data for South Williamsport: nearby ZIP 17702 weather · frost dates · planting calendar · Pennsylvania frost dates
Nearby towns & communities
Duboistown
Faxon
Garden View
Hughesville
Jersey Shore
Kenmar
Montgomery
Montoursville
Muncy
Oval
Picture Rocks
Rauchtown
Salladasburg
Williamsport
Climate data from the nearest NOAA station, Williamsport 2, Pa (6.6 mi from South Williamsport). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.