Flat Lake (US, IL), Weather

39.0525° N, 90.5771° W

06.06.2026 (Saturday)

Quite high air temperature (26.0 °C)
Moderate winds forecast (6.2 m/s)
Strong wind gusts forecast (12.9 m/s)

07.06.2026 (Sunday)

Quite high air temperature (26.2 °C)
Heavy rain detected – dangerous conditions (2.4 mm)

08.06.2026 (Monday)

Very high air temperature (31.2 °C)
Heavy rain detected – dangerous conditions (5.4 mm)
Moderate winds forecast (6.4 m/s)
Strong wind gusts forecast (12.8 m/s)
High UV - risk of sunburn/overheating (10)

09.06.2026 (Tuesday)

Very high air temperature (33.6 °C)
Heavy rain detected – dangerous conditions (3.3 mm)
Strong wind gusts forecast (11.7 m/s)

10.06.2026 (Wednesday)

Very high air temperature (33.8 °C)
Rain detected – conditions may be challenging (0.1 mm)
Moderate winds forecast (5.1 m/s)

11.06.2026 (Thursday)

Very high air temperature (33.9 °C)
Moderate winds forecast (5.9 m/s)
Strong wind gusts forecast (12.4 m/s)

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Current Conditions in Flat Lake (US, IL)

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Feels like

Wind	Humidity	Moon rise

UV Index	Pressure	Moon

Wind	UV Index

Humidity	Pressure

Moon rise	Moon

Flat Lake (US, IL), Hourly Forecast

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	Today


	Air temperature,°C

	Wind force & direction, knots



	UV index

Flat Lake (US, IL) 10-day weather forecast

Closest meteostation (10.69km):

Flat Lake (US, IL) Wind forecast

Wind direction is Southwest, wind speed varies between 6.7 and 13.4 mph with gusts up to 31.2 mph. The sky is clear with a chance of rain 0%.
Wind and wave weather forecast for Flat Lake (US, IL) , United States contains detailed information about local wind speed, direction, and gusts. Wave forecast includes wave height and period.
These forecasts for Flat Lake (US, IL) are based on the GFS model and were created for windsurfing, kitesurfing, sailing and other extreme sports activities. All data updates 4 times a day. Predictions are available in steps from 1 to 3 hours for up to 10 days.
Use professional weather parameters: wind barbs, weather fronts, isobars, and others. Study weather history for the past 14 years (2012-2026). Create sailing, hiking and biking routes with weather in each point.
Download Windy.app in the App Store and Google Play Store.

Flat Lake (US, IL), weather report: temperature, and more

The temperature low is +20°C and the high is +30°C. The sky is clear with a chance of rain 0%. 10 day weather forecast for Flat Lake (US, IL), on this page also contains accurate information about cloud coverage, moon phases, and other basic and advanced weather elements.

Flat Lake (US, IL), current weather temperature for today and the mid-range forecast are based on the major global GFS weather model with 27 km (16.7 mi) spatial resolution provided by the United States National Weather Service (NWS) of the National Oceanic and Atmospheric Administration (NOAA). All data updates 4 times a day with a forecast step of 3 hours.

If you need a 30 day temperature forecast for Flat Lake (US, IL), or a long-range temperature forecast, check the Weather History (Statistics) section of the main spot page you can find in the search or on the weather map.

It contains the day and night temperature history in Flat Lake (US, IL), for the past 10 years (2021–2021) and the average values for the decade. These statictics are a reanalysis of the weather forecasts from the ECMWF (European Centre for Medium-Range Weather Forecasts), the second major global weather model. The data is updated every year.

You can use this weather forecast and history by the Windy.app especially for all major sports and outdoor activities such as surfing, sailing, diving, fishing, paragliding, cycling, hiking, and others, as well as a general forecast for any situation.