Ontario, IN Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Ontario, a community in Lagrange County, Indiana.

Overnight

59°F

Clear

Clear, with a low around 59. South wind 0 to 5 mph.

7-day forecast for Ontario

When	Temp	Forecast	Wind	Precip
Overnight	59°F	Clear	0 to 5 mph S	0%
Tuesday	84°F	Sunny	0 to 5 mph S	0%
Tuesday Night	60°F	Mostly Clear	0 to 5 mph S	0%
Wednesday	85°F	Mostly Sunny	0 to 10 mph SW	1%
Wednesday Night	66°F	Chance Showers And Thunderstorms	0 to 5 mph SW	70%
Thursday	81°F	Rain Showers Likely	5 mph SW	70%
Thursday Night	63°F	Showers And Thunderstorms Likely then Chance Showers And Thunderstorms	0 to 5 mph SW	68%
Friday	83°F	Partly Sunny then Chance Showers And Thunderstorms	0 to 5 mph SW	28%
Friday Night	63°F	Chance Showers And Thunderstorms then Partly Cloudy	0 to 5 mph SW	28%
Saturday	85°F	Mostly Sunny	0 to 10 mph SW	11%
Saturday Night	67°F	Slight Chance Showers And Thunderstorms	5 to 10 mph SW	22%
Sunday	87°F	Slight Chance Rain Showers then Slight Chance Showers And Thunderstorms	5 to 15 mph SW	22%
Sunday Night	69°F	Chance Showers And Thunderstorms	10 to 15 mph SW	39%
Monday	86°F	Chance Rain Showers	10 mph SW	39%

Forecast source: National Weather Service (api.weather.gov) for Ontario (41.699, -85.385). Updated through the day.

Growing snapshot for Ontario

Last spring frost

Apr 26

First fall frost

Oct 21

Growing season

176 days

Hardiness zone

More local growing data for Ontario: nearby ZIP 46746 weather · frost dates · planting calendar · Indiana frost dates

Nearby towns & communities

Adams Lake Cree Lake Howe Lagrange Mongo Otter Lake Scott Shipshewana Shipshewana Lake South Milford Stroh Topeka Wildwood

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Climate data from the nearest NOAA station, Lagrange, In (6.4 mi from Ontario). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.