Plymouth, IL Weather & Growing Conditions
Tonight
51°F
Mostly Cloudy
Mostly cloudy, with a low around 51. Southwest wind 9 to 13 mph, with gusts as high as 22 mph. New rainfall amounts less than a tenth of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 51°F | Mostly Cloudy | 9 to 13 mph SW | 6% |
| Wednesday | 57°F | Mostly Cloudy | 13 to 18 mph WSW | 9% |
| Wednesday Night | 44°F | Mostly Cloudy | 12 mph WSW | 3% |
| Thursday | 57°F | Slight Chance Rain Showers | 9 to 14 mph W | 18% |
| Thursday Night | 43°F | Slight Chance Rain Showers | 6 to 9 mph NW | 23% |
| Friday | 52°F | Partly Sunny | 7 to 10 mph N | 11% |
| Friday Night | 32°F | Partly Cloudy | 1 to 6 mph N | 0% |
| Saturday | 52°F | Mostly Sunny | 1 to 5 mph NW | 0% |
| Saturday Night | 33°F | Mostly Clear | 2 mph WNW | 1% |
| Sunday | 58°F | Sunny | 2 to 8 mph W | 2% |
| Sunday Night | 35°F | Clear | 3 mph WSW | 0% |
| Monday | 64°F | Sunny | 2 to 8 mph SW | 0% |
| Monday Night | 40°F | Mostly Clear | 2 to 6 mph WSW | 0% |
| Tuesday | 65°F | Sunny | 5 mph NW | 0% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Plymouth, IL
Last spring frost
Apr 13
First fall frost
Oct 22
Growing season
191 days
Hardiness zone
6a
Explore more for Plymouth, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, Bentley, Il (13.4 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.