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New Boston, IL Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for New Boston, a city in Mercer County, Illinois.

Today
85°F
Slight Chance Rain Showers then Slight Chance Showers And Thunderstorms
A slight chance of rain showers before 1pm, then a slight chance of showers and thunderstorms. Mostly cloudy, with a high near 85. South wind around 10 mph. Chance of precipitation is 20%.

7-day forecast for New Boston

WhenTempForecastWindPrecip
Today 85°F Slight Chance Rain Showers then Slight Chance Showers And Thunderstorms 10 mph S 24%
Tonight 66°F Chance Showers And Thunderstorms then Showers And Thunderstorms 5 mph W 78%
Sunday 72°F Showers And Thunderstorms 10 to 15 mph NE 80%
Sunday Night 58°F Slight Chance Showers And Thunderstorms then Showers And Thunderstorms Likely 10 to 15 mph NE 57%
Monday 65°F Showers And Thunderstorms Likely 10 to 15 mph NE 62%
Monday Night 53°F Chance Rain Showers 10 mph NE 51%
Tuesday 64°F Chance Rain Showers 10 mph NE 35%
Tuesday Night 49°F Partly Cloudy 5 to 10 mph NE 5%
Wednesday 68°F Mostly Sunny 5 mph NE 1%
Wednesday Night 52°F Partly Cloudy 0 to 5 mph NE 1%
Thursday 70°F Mostly Sunny 0 to 5 mph NE 5%
Thursday Night 54°F Partly Cloudy 0 to 5 mph NE 4%
Friday 73°F Mostly Sunny 0 to 5 mph NE 4%
Friday Night 55°F Partly Cloudy 0 to 5 mph E 5%

Forecast source: National Weather Service (api.weather.gov) for New Boston (41.170, -91.000). Updated through the day.

Growing snapshot for New Boston

Last spring frost
Apr 14
First fall frost
Oct 24
Growing season
190 days
Hardiness zone
5b

More local growing data for New Boston: nearby ZIP 61272 weather · frost dates · planting calendar · Illinois frost dates

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Climate data from the nearest NOAA station, New Boston Dam 17, Il (4.7 mi from New Boston). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.