Prosser, WA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Prosser, a city in Benton County, Washington.
Today
90°F
Areas Of Smoke
Areas of smoke. Sunny, with a high near 90. Northwest wind 2 to 7 mph.
7-day forecast for Prosser
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 90°F | Areas Of Smoke | 2 to 7 mph NW | 0% |
| Tonight | 55°F | Areas Of Smoke | 1 to 6 mph NW | 0% |
| Wednesday | 96°F | Areas Of Smoke | 3 mph N | 0% |
| Wednesday Night | 58°F | Patchy Smoke then Clear | 2 mph W | 0% |
| Thursday | 101°F | Sunny | 3 mph SW | 0% |
| Thursday Night | 61°F | Clear | 2 to 6 mph W | 0% |
| Friday | 99°F | Sunny | 5 mph W | 0% |
| Friday Night | 60°F | Clear | 2 to 8 mph W | 0% |
| Saturday | 96°F | Sunny | 3 mph W | 0% |
| Saturday Night | 58°F | Mostly Clear | 3 to 9 mph W | 0% |
| Sunday | 91°F | Sunny | 6 mph W | 0% |
| Sunday Night | 56°F | Mostly Clear | 7 mph W | 0% |
| Monday | 90°F | Sunny | 5 mph SW | 0% |
| Monday Night | 55°F | Clear | 6 mph W | 0% |
Forecast source: National Weather Service (api.weather.gov) for Prosser (46.209, -119.768). Updated through the day.
Growing snapshot for Prosser
Last spring frost
Apr 14
First fall frost
Oct 22
Growing season
189 days
Hardiness zone
7b
More local growing data for Prosser: nearby ZIP 99350 weather · frost dates · planting calendar · Washington frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Prosser, Wa (4.2 mi from Prosser). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.