St. Augustine, IL Weather & Growing Conditions
Tonight
52°F
Light Rain Likely
Rain likely before 2am, then a slight chance of rain showers between 2am and 4am. Mostly cloudy, with a low around 52. South southwest wind 8 to 12 mph, with gusts as high as 23 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 52°F | Light Rain Likely | 8 to 12 mph SSW | 62% |
| Wednesday | 57°F | Slight Chance Rain Showers then Mostly Cloudy | 13 to 16 mph SW | 18% |
| Wednesday Night | 45°F | Mostly Cloudy | 8 to 12 mph SW | 6% |
| Thursday | 57°F | Mostly Cloudy then Slight Chance Light Rain | 8 to 13 mph W | 19% |
| Thursday Night | 42°F | Chance Light Rain | 7 mph NW | 30% |
| Friday | 53°F | Mostly Cloudy | 6 to 10 mph N | 14% |
| Friday Night | 35°F | Mostly Cloudy | 0 to 5 mph N | 1% |
| Saturday | 52°F | Mostly Sunny | 0 to 3 mph NW | 2% |
| Saturday Night | 35°F | Partly Cloudy | 2 mph W | 2% |
| Sunday | 59°F | Sunny | 2 to 8 mph WNW | 11% |
| Sunday Night | 35°F | Mostly Clear | 5 mph W | 3% |
| Monday | 63°F | Sunny | 2 to 10 mph SW | 2% |
| Monday Night | 40°F | Mostly Clear | 6 mph W | 0% |
| Tuesday | 65°F | Sunny | 6 mph NW | 0% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for St. Augustine, IL
Last spring frost
Apr 22
First fall frost
Oct 19
Growing season
177 days
Hardiness zone
5b
Explore more for St. Augustine, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, Avon, Il (6.1 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.