Mason, IL Weather & Growing Conditions
This Afternoon
96°F
Chance Showers And Thunderstorms
A chance of showers and thunderstorms. Sunny, with a high near 96. Heat index values as high as 104. Northeast wind around 5 mph. Chance of precipitation is 30%. New rainfall amounts less than a tenth of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 96°F | Chance Showers And Thunderstorms | 5 mph NE | 29% |
| Tonight | 71°F | Slight Chance Showers And Thunderstorms then Partly Cloudy | 6 mph ESE | 23% |
| Saturday | 94°F | Mostly Sunny | 3 to 8 mph SSW | 10% |
| Saturday Night | 71°F | Mostly Cloudy | 3 to 7 mph SSW | 6% |
| Sunday | 92°F | Mostly Sunny then Slight Chance Showers And Thunderstorms | 3 to 7 mph WNW | 20% |
| Sunday Night | 64°F | Chance Showers And Thunderstorms | 7 mph NNE | 43% |
| Monday | 79°F | Rain Showers Likely | 7 to 10 mph NE | 57% |
| Monday Night | 58°F | Showers And Thunderstorms Likely then Chance Showers And Thunderstorms | 7 to 13 mph NNE | 55% |
| Tuesday | 72°F | Chance Showers And Thunderstorms | 12 mph NNE | 36% |
| Tuesday Night | 54°F | Mostly Cloudy | 5 to 12 mph NNE | 6% |
| Wednesday | 74°F | Partly Sunny | 6 to 9 mph N | 3% |
| Wednesday Night | 54°F | Partly Cloudy | 2 to 9 mph NNE | 3% |
| Thursday | 75°F | Mostly Sunny | 3 to 8 mph NNE | 3% |
| Thursday Night | 56°F | Partly Cloudy | 2 to 7 mph NNE | 3% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Mason, IL
Last spring frost
Apr 13
First fall frost
Oct 24
Growing season
191 days
Hardiness zone
6b
Explore more for Mason, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, Effingham 3Sw, Il (11.2 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.