Bismarck, IL Weather & Growing Conditions
This Afternoon
84°F
Slight Chance Showers And Thunderstorms
A slight chance of showers and thunderstorms. Mostly cloudy, with a high near 84. South wind around 6 mph. Chance of precipitation is 20%. New rainfall amounts less than a tenth of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 84°F | Slight Chance Showers And Thunderstorms | 6 mph S | 19% |
| Tonight | 68°F | Mostly Cloudy | 6 mph S | 14% |
| Sunday | 81°F | Slight Chance Rain Showers then Chance Showers And Thunderstorms | 3 to 12 mph N | 54% |
| Sunday Night | 58°F | Chance Showers And Thunderstorms | 13 mph NE | 49% |
| Monday | 69°F | Showers And Thunderstorms Likely | 14 mph ENE | 57% |
| Monday Night | 54°F | Chance Rain Showers | 13 mph ENE | 41% |
| Tuesday | 67°F | Chance Rain Showers | 13 mph NE | 33% |
| Tuesday Night | 54°F | Chance Rain Showers then Mostly Cloudy | 7 to 13 mph NNE | 25% |
| Wednesday | 68°F | Partly Sunny | 9 mph NNE | 10% |
| Wednesday Night | 54°F | Mostly Cloudy | 3 to 9 mph N | 4% |
| Thursday | 71°F | Partly Sunny | 7 mph NNE | 3% |
| Thursday Night | 55°F | Mostly Cloudy | 2 to 7 mph NNE | 6% |
| Friday | 74°F | Partly Sunny | 3 to 7 mph NNE | 6% |
| Friday Night | 54°F | Partly Cloudy | 2 to 6 mph NE | 3% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Bismarck, IL
Last spring frost
Apr 21
First fall frost
Oct 20
Growing season
181 days
Hardiness zone
6a
Explore more for Bismarck, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, Danville, Il (7.6 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.