Harvard, IL Weather & Growing Conditions
Tonight
58°F
Rain
Rain. Cloudy. Low around 58, with temperatures rising to around 61 overnight. South wind around 15 mph, with gusts as high as 30 mph. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 58°F | Rain | 15 mph S | 84% |
| Wednesday | 61°F | Rain Likely then Rain Showers Likely | 15 mph SSW | 57% |
| Wednesday Night | 46°F | Chance Rain Showers | 15 mph SW | 29% |
| Thursday | 55°F | Rain Showers Likely | 10 to 15 mph WSW | 56% |
| Thursday Night | 41°F | Chance Rain Showers | 5 to 10 mph NW | 47% |
| Friday | 50°F | Slight Chance Rain Showers then Mostly Cloudy | 10 mph N | 19% |
| Friday Night | 34°F | Partly Cloudy | 0 to 5 mph NNW | 2% |
| Saturday | 51°F | Mostly Sunny | 0 to 5 mph WNW | 2% |
| Saturday Night | 34°F | Partly Cloudy | 0 to 5 mph WSW | 7% |
| Sunday | 57°F | Mostly Sunny then Slight Chance Rain | 5 to 10 mph W | 17% |
| Sunday Night | 35°F | Mostly Clear | 0 to 5 mph W | 7% |
| Monday | 60°F | Sunny | 5 to 10 mph WSW | 2% |
| Monday Night | 40°F | Mostly Clear | 5 to 10 mph W | 2% |
| Tuesday | 60°F | Mostly Sunny | 5 to 10 mph WNW | 1% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Harvard, IL
Last spring frost
Apr 28
First fall frost
Oct 12
Growing season
166 days
Hardiness zone
5b
Explore more for Harvard, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, Marengo, Il (11 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.