Roslyn, WA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Roslyn, a city in Kittitas County, Washington.
Today
67°F
Mostly Sunny
Mostly sunny. High near 67, with temperatures falling to around 65 in the afternoon. West wind 1 to 5 mph.
7-day forecast for Roslyn
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 67°F | Mostly Sunny | 1 to 5 mph W | 0% |
| Tonight | 51°F | Mostly Clear | 3 mph NW | 0% |
| Sunday | 68°F | Sunny | 3 mph E | 0% |
| Sunday Night | 52°F | Mostly Clear | 3 mph NW | 0% |
| Monday | 64°F | Sunny | 3 to 8 mph W | 0% |
| Monday Night | 47°F | Partly Cloudy | 10 mph W | 0% |
| Tuesday | 59°F | Mostly Sunny | 7 to 10 mph W | 0% |
| Tuesday Night | 43°F | Mostly Cloudy | 7 mph W | 0% |
| Wednesday | 56°F | Partly Sunny | 6 mph W | 0% |
| Wednesday Night | 44°F | Mostly Cloudy | 2 to 6 mph W | 3% |
| Thursday | 55°F | Partly Sunny then Slight Chance Rain Showers | 5 mph W | 15% |
| Thursday Night | 43°F | Slight Chance Rain Showers | 5 mph W | 16% |
| Friday | 53°F | Partly Sunny | 6 mph W | 14% |
| Friday Night | 41°F | Partly Cloudy | 6 mph W | 11% |
Forecast source: National Weather Service (api.weather.gov) for Roslyn (47.270, -121.141). Updated through the day.
Growing snapshot for Roslyn
Last spring frost
May 14
First fall frost
Oct 17
Growing season
154 days
Hardiness zone
7a
More local growing data for Roslyn: nearby ZIP 98925 weather · frost dates · planting calendar · Washington frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Stampede Pass, Wa (2.8 mi from Roslyn). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.