Marietta, IL Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Marietta, a village in Fulton County, Illinois.
Today
88°F
Sunny
Sunny, with a high near 88. South southwest wind around 6 mph.
7-day forecast for Marietta
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 88°F | Sunny | 6 mph SSW | 0% |
| Tonight | 67°F | Partly Cloudy then Slight Chance Showers And Thunderstorms | 3 mph SSE | 23% |
| Wednesday | 84°F | Chance Showers And Thunderstorms | 3 mph S | 54% |
| Wednesday Night | 65°F | Chance Showers And Thunderstorms then Showers And Thunderstorms | 0 to 3 mph NNW | 86% |
| Thursday | 81°F | Showers And Thunderstorms | 1 mph S | 79% |
| Thursday Night | 63°F | Partly Cloudy | 0 mph | 8% |
| Friday | 83°F | Mostly Sunny | 0 mph | 5% |
| Friday Night | 65°F | Slight Chance Showers And Thunderstorms | 0 mph | 17% |
| Saturday | 86°F | Slight Chance Showers And Thunderstorms then Sunny | 2 mph SW | 15% |
| Saturday Night | 70°F | Mostly Clear | 0 to 3 mph SSW | 8% |
| Sunday | 88°F | Sunny | 5 to 9 mph SSW | 6% |
| Sunday Night | 70°F | Partly Cloudy then Slight Chance Showers And Thunderstorms | 6 mph SSW | 18% |
| Monday | 88°F | Slight Chance Showers And Thunderstorms then Mostly Sunny | 7 mph SSW | 18% |
| Monday Night | 71°F | Slight Chance Showers And Thunderstorms | 5 mph SW | 29% |
Forecast source: National Weather Service (api.weather.gov) for Marietta (40.499, -90.393). Updated through the day.
Growing snapshot for Marietta
Last spring frost
Apr 17
First fall frost
Oct 22
Growing season
185 days
Hardiness zone
6a
More local growing data for Marietta: nearby ZIP 61459 weather · frost dates · planting calendar · Illinois frost dates
Nearby towns & communities
Astoria
Avon
Bryant
Canton
Cuba
Dunfermline
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Fairview
Farmington
Goofy Ridge
Ipava
Lewistown
Liverpool
London Mills
Norris
Smithfield
St. David
Table Grove
Vermont
Climate data from the nearest NOAA station, Prairie City 2S, Il (6.1 mi from Marietta). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.