Seneca, OR Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Seneca, a city in Grant County, Oregon.
This Afternoon
50°F
Mostly Cloudy
Mostly cloudy. High near 50, with temperatures falling to around 43 in the afternoon. Southeast wind 3 to 8 mph.
7-day forecast for Seneca
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 50°F | Mostly Cloudy | 3 to 8 mph SE | 2% |
| Tonight | 21°F | Partly Cloudy | 2 mph NW | 1% |
| Wednesday | 54°F | Sunny | 2 mph NW | 0% |
| Wednesday Night | 25°F | Mostly Cloudy then Slight Chance Snow Showers | 1 mph SW | 19% |
| Thursday | 48°F | Partly Sunny | 0 to 3 mph NW | 12% |
| Thursday Night | 22°F | Mostly Clear | 1 mph S | 5% |
| Friday | 53°F | Partly Sunny | 3 mph S | 5% |
| Friday Night | 25°F | Partly Cloudy | 2 mph SE | 1% |
| Saturday | 58°F | Mostly Sunny | 2 to 12 mph SE | 0% |
| Saturday Night | 28°F | Mostly Cloudy | 5 to 9 mph SE | 0% |
| Sunday | 56°F | Partly Sunny | 2 to 7 mph SW | 6% |
| Sunday Night | 26°F | Mostly Cloudy | 2 mph SE | 6% |
| Monday | 55°F | Partly Sunny | 1 to 5 mph S | 8% |
| Monday Night | 26°F | Mostly Cloudy | 3 mph S | 10% |
Forecast source: National Weather Service (api.weather.gov) for Seneca (44.135, -118.976). Updated through the day.
Growing snapshot for Seneca
Growing season
24 days
Hardiness zone
5b
More local growing data for Seneca: nearby ZIP 97873 weather · frost dates · planting calendar · Oregon frost dates
Nearby towns & communities
Canyon City
Dayville
Granite
Greenhorn
John Day
Long Creek
Monument
Mount Vernon
Prairie City
Sumpter
Climate data from the nearest NOAA station, Seneca, Or (1.2 mi from Seneca). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 3, 2026.