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Hourly Forecast
Daylight Hours
06:33
Sunrise
18:46
Sunset
Moon
Waxing Crescent
12:34
Moonrise
20:43
Moonset
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Weather in Merrimack today, September 16, 2026
Merrimack starts September 16, 2026 under largely sunny skies, with bright spells setting the tone from the outset. Outdoor plans should enjoy long stretches of open sky as the day unfolds.
Temperatures climb from an overnight low near 11°C toward a daytime high of about 27°C. Expect humidity between 49% and 87%, most humid near 23:00. A lighter breeze peaks around 21:00 near 2.1 km/h.
Later hours favour clearer intervals, as cloud stays near 10% around 23:00. The afternoon is the better half for outdoor time. Expect visibility around 16.1 km. Sunrise is at 06:33 and sunset at 18:46, giving 12 hours 13 minutes of sunlight today.
In short, September 16, 2026 looks like a fine day in Merrimack for being outside, peaking around 27°C.
Frequently asked questions about weather in Merrimack
How warm does it get in Merrimack?
The warmest month in Merrimack is July, with average high temperatures of 29°C. The average temperature during this period is around 24°C.
How cold does it get in Merrimack?
The coldest month in Merrimack is January, with average low temperatures of -5°C. The average temperature during this period is around -2°C.
What is the wettest time of year in Merrimack?
The wettest month in Merrimack is December, with an average of 121mm of precipitation.
What is the driest time of year in Merrimack?
The driest month in Merrimack is February, with an average of 79mm of precipitation.
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