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7 Days
14 Days
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Monthly
Precipitation
Temperature
Wind
Temperature Unit Selection
°Celsius
°Fahrenheit
Monthly Historical Averages
Merrimack, NH
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September
Average Temperature
High
23°
Feels 23
Low
11°
Feels 11
Average Precipitation
9 Days
Rain amount
65.2mm
Snow amount
0cm
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Daily Historical Averages
September 2026
S
M
T
W
T
F
S
1
2
3
4
5
6
7
8
9
10
28°
11
24°
12
24°
13
23°
14
21°
15
22°
16
26°
17
25°
18
24°
19
20°
20
20°
21
20°
22
21°
23
21°
24
21°
25
26
27
28
29
30
Forecast
Thursday, September 10, 2026
Day
28°
Feels 29
Wind
28 km/h W
Gust
42 km/h
Humidity
44%
P.O.P
40%
Rain
<1 mm
Night
15°
Feels 14
Wind
22 km/h W
Gust
33 km/h
Humidity
77%
P.O.P
30%
Historical Averages
Sep 10
High
Feels
Low
Feels
Precip Frequency
Total Daylight
Humidity
Historical Averages are based on data recorded from 2000 onwards.