Harmony, IL Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Harmony, a community in Mchenry County, Illinois.
This Afternoon
68°F
Rain Likely
Rain likely and a slight chance of thunderstorms. Mostly cloudy. High near 68, with temperatures falling to around 66 in the afternoon. South wind around 15 mph, with gusts as high as 35 mph. Chance of precipitation is 70%. New rainfall amounts less than a tenth of an inch possible.
7-day forecast for Harmony
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 68°F | Rain Likely | 15 mph S | 74% |
| Tonight | 58°F | Rain | 15 mph SSE | 88% |
| Wednesday | 61°F | Rain Likely | 15 mph SSW | 56% |
| Wednesday Night | 47°F | Mostly Cloudy then Slight Chance Rain | 15 mph SW | 24% |
| Thursday | 55°F | Chance Rain | 10 to 15 mph WSW | 41% |
| Thursday Night | 41°F | Chance Rain | 5 to 10 mph NW | 47% |
| Friday | 51°F | Slight Chance Rain then Mostly Cloudy | 10 mph N | 21% |
| Friday Night | 34°F | Partly Cloudy | 0 to 5 mph NNW | 3% |
| Saturday | 51°F | Mostly Sunny | 0 to 5 mph WNW | 4% |
| Saturday Night | 34°F | Partly Cloudy | 0 to 5 mph WSW | 6% |
| Sunday | 56°F | Mostly Sunny then Slight Chance Rain | 5 to 10 mph W | 16% |
| Sunday Night | 35°F | Mostly Clear | 5 mph W | 5% |
| Monday | 60°F | Sunny | 5 to 15 mph WSW | 3% |
| Monday Night | 40°F | Mostly Clear | 5 to 10 mph W | 2% |
Forecast source: National Weather Service (api.weather.gov) for Harmony (42.159, -88.529). Updated through the day.
Growing snapshot for Harmony
Last spring frost
Apr 28
First fall frost
Oct 12
Growing season
166 days
Hardiness zone
5b
More local growing data for Harmony: nearby ZIP 60180 weather · frost dates · planting calendar · Illinois frost dates
Nearby towns & communities
Algonquin
Bull Valley
Cary
Chemung
Coral
Crystal Lake
Fox River Grove
Franklinville
Greenwood
Hartland
Harvard
Hebron
Huntley
Johnsburg
Lake Barrington
Lake in the Hills
Lakemoor
Lakewood
Lawrence
Marengo
McCullom Lake
McHenry
Oakwood Hills
Prairie Grove
Richmond
Ridgefield
Riley
Ringwood
Solon Mills
Spring Grove
Climate data from the nearest NOAA station, Marengo, Il (5.3 mi from Harmony). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 3, 2026.