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Hourly Forecast
Daylight Hours
06:39
Sunrise
18:55
Sunset
Moon
Waxing Crescent
11:36
Moonrise
20:24
Moonset
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Weather in McHenry today, September 15, 2026
Expect a muted, overcast feel in McHenry on September 15, 2026 as cloud persists. Brighter breaks, if they arrive, should stay brief.
The day peaks near 26°C and cools toward 18°C. The air stays humid, with relative humidity between 76% and 96% and the peak around 20:00. Airflow remains manageable, reaching about 4.2 km/h around 16:00.
Through the afternoon cloud remains the main feature, with cover near 100% around 17:00. Bright spells should stay limited even as the day wears on. Horizontal visibility sits around 14.7 km, briefly nearer 13.0 km. Expect sunrise at 06:39, sunset at 18:55, and 12 hours 16 minutes of sunlight today overall.
Taken together, overcast skies in McHenry on September 15, 2026 favour indoor or covered options, with temperatures near 26°C.
Frequently asked questions about weather in McHenry
How warm does it get in McHenry?
The warmest month in McHenry 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 McHenry?
The coldest month in McHenry is January, with average low temperatures of -7°C. The average temperature during this period is around -4°C.
What is the wettest time of year in McHenry?
The wettest month in McHenry is May, with an average of 123mm of precipitation.
What is the driest time of year in McHenry?
The driest month in McHenry is February, with an average of 49mm of precipitation.
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