See exactly when rain will start and stop with a minute-by-minute precipitation nowcast for the next hour.
28°
Clear
Feels Like: 23°
Min: 19°
Max: 29°
The next few hours will be overcast, with today reaching 29°C and dropping to 17°C. The coming days will be drizzle
Compare today's weather with yesterday's data and track temperature trends over time.
Hourly Forecast
Daylight Hours
06:38
Sunrise
18:54
Sunset
Moon
Waxing Crescent
11:34
Moonrise
20:23
Moonset
Daily Forecast
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Wednesday
Thursday
Friday
Saturday
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Thursday
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Weather in Prospect Heights today, September 15, 2026
Prospect Heights stays under cloudy skies on September 15, 2026, with only brief brighter breaks. Plan for a day that feels grey more often than open.
The temperature range runs from about 19°C up to 29°C. Moisture in the air spans 54%-86%, with the highest values around 22:00. Winds stay light, near 4.0 km/h by 17:00, so the day feels still more than breezy.
The afternoon keeps an overcast feel, as cloud reaches about 100% around 20:00. Outdoor plans may still want a flexible backup. Horizontal visibility holds close to 16.1 km. The sun rises at 06:38 and sets at 18:54, for a total of 12 hours 16 minutes of sunlight today.
In short, cloud leads the story in Prospect Heights on September 15, 2026; expect limited sun and a peak around 29°C.
Frequently asked questions about weather in Prospect Heights
How warm does it get in Prospect Heights?
The warmest month in Prospect Heights is July, with average high temperatures of 28°C. The average temperature during this period is around 24°C.
How cold does it get in Prospect Heights?
The coldest month in Prospect Heights is January, with average low temperatures of -6°C. The average temperature during this period is around -4°C.
What is the wettest time of year in Prospect Heights?
The wettest month in Prospect Heights is May, with an average of 126mm of precipitation.
What is the driest time of year in Prospect Heights?
The driest month in Prospect Heights is February, with an average of 51mm of precipitation.
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