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Oswego, SC Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Oswego, a community in Sumter County, South Carolina.

This Afternoon
95°F
Sunny
Sunny, with a high near 95. Heat index values as high as 102. Southwest wind around 3 mph.

7-day forecast for Oswego

WhenTempForecastWindPrecip
This Afternoon 95°F Sunny 3 mph SW 12%
Tonight 71°F Chance Showers And Thunderstorms 2 mph NW 30%
Saturday 92°F Patchy Fog then Chance Showers And Thunderstorms 0 to 5 mph NE 40%
Saturday Night 71°F Chance Showers And Thunderstorms then Partly Cloudy 0 to 5 mph NE 33%
Sunday 91°F Partly Sunny then Chance Showers And Thunderstorms 2 mph NE 28%
Sunday Night 70°F Chance Showers And Thunderstorms then Partly Cloudy 2 mph E 28%
Monday 92°F Mostly Sunny then Chance Showers And Thunderstorms 0 to 3 mph E 39%
Monday Night 71°F Chance Showers And Thunderstorms 0 to 3 mph E 40%
Tuesday 88°F Chance Rain Showers then Chance Showers And Thunderstorms 1 to 7 mph NE 54%
Tuesday Night 69°F Chance Showers And Thunderstorms 3 to 8 mph NE 54%
Wednesday 84°F Partly Sunny then Chance Showers And Thunderstorms 8 to 13 mph NE 31%
Wednesday Night 65°F Chance Showers And Thunderstorms then Partly Cloudy 8 to 13 mph NE 31%
Thursday 82°F Mostly Sunny 12 mph NE 13%
Thursday Night 63°F Slight Chance Showers And Thunderstorms 5 to 10 mph NE 15%

Forecast source: National Weather Service (api.weather.gov) for Oswego (34.006, -80.286). Updated through the day.

Growing snapshot for Oswego

Last spring frost
Mar 24
First fall frost
Nov 7
Growing season
230 days
Hardiness zone
8b

More local growing data for Oswego: nearby ZIP 29153 weather · frost dates · planting calendar · South Carolina frost dates

Nearby towns & communities

All South Carolina locations ›

Climate data from the nearest NOAA station, Sumter, Sc (3.8 mi from Oswego). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 18, 2026.