Onalaska, WA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Onalaska, a community in Lewis County, Washington.
Overnight
48°F
Mostly Cloudy
Mostly cloudy, with a low around 48. Wind around 0 mph.
7-day forecast for Onalaska
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 48°F | Mostly Cloudy | 0 mph | 0% |
| Saturday | 75°F | Partly Sunny | 2 mph NW | 0% |
| Saturday Night | 48°F | Mostly Clear | 1 mph NNW | 0% |
| Sunday | 76°F | Mostly Sunny | 0 to 3 mph NNW | 0% |
| Sunday Night | 48°F | Mostly Clear | 0 to 3 mph NNW | 0% |
| Monday | 73°F | Partly Sunny | 0 to 3 mph NW | 0% |
| Monday Night | 48°F | Partly Cloudy | 0 to 3 mph NNW | 0% |
| Tuesday | 69°F | Partly Sunny | 0 to 3 mph NNW | 0% |
| Tuesday Night | 46°F | Partly Cloudy | 0 to 3 mph NW | 3% |
| Wednesday | 68°F | Partly Sunny | 1 mph NNW | 3% |
| Wednesday Night | 47°F | Mostly Cloudy | 1 mph NNW | 2% |
| Thursday | 66°F | Mostly Cloudy then Slight Chance Light Rain | 0 to 3 mph N | 15% |
| Thursday Night | 46°F | Slight Chance Light Rain then Mostly Cloudy | 3 mph N | 15% |
| Friday | 64°F | Partly Sunny | 1 to 5 mph NNW | 12% |
Forecast source: National Weather Service (api.weather.gov) for Onalaska (46.578, -122.711). Updated through the day.
Growing snapshot for Onalaska
Last spring frost
Apr 5
First fall frost
Oct 25
Growing season
196 days
Hardiness zone
8a
More local growing data for Onalaska: nearby ZIP 98542 weather · frost dates · planting calendar · Washington frost dates
Nearby towns & communities
Ashford
Centralia
Chehalis
Fords Prairie
Grand Mound
Morton
Mossyrock
Napavine
Packwood
Pe Ell
Toledo
Vader
Winlock
Climate data from the nearest NOAA station, Toledo Faa Ap, Wa (5.5 mi from Onalaska). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.