Climate and monthly weather forecastMendham, NJ
Climate and monthly weather forecast
Weather in January
January, the same as December, is a wintry winter month in Mendham, New Jersey, with an average temperature fluctuating between 22.3°F (-5.4°C) and 35.1°F (1.7°C). January brings the lowest temperatures, with an average high of 35.1°F (1.7°C) and an average low of 22.3°F (-5.4°C). Weather in January »Weather in February
February, the last month of the winter in Mendham, is also a wintry month, with an average temperature fluctuating between 23.7°F (-4.6°C) and 38.3°F (3.5°C). The average high-temperature in February, at a still cold 38.3°F (3.5°C), reveals a modest deviation from January's 35.1°F (1.7°C). Weather in February »Weather in March
March, the first month of the spring in Mendham, is a frosty month, with an average temperature ranging between max 46.6°F (8.1°C) and min 31.5°F (-0.3°C). As Mendham transitions into March, the average high-temperature is observed to slightly rise from a cold 38.3°F (3.5°C) in February to a chilly 46.6°F (8.1°C). Weather in March »Weather in April
April is a refreshing spring month in Mendham, New Jersey, with an average temperature fluctuating between 58.6°F (14.8°C) and 41.5°F (5.3°C). In April, the meteorological conditions change with the average high-temperature moving from a chilly 46.6°F (8.1°C) in March to a refreshing 58.6°F (14.8°C). Weather in April »Weather in May
The last month of the spring, May, is an agreeable month in Mendham, New Jersey, with an average temperature fluctuating between 69.6°F (20.9°C) and 50.9°F (10.5°C). The beginning of May signals a rise in the average high-temperature, moving from a refreshing 58.6°F (14.8°C) in April to an agreeable 69.6°F (20.9°C). Weather in May »Weather in June
The first month of the summer, June, is a moderately hot month in Mendham, New Jersey, with temperature in the range of an average high of 77.5°F (25.3°C) and an average low of 58.5°F (14.7°C). Mendham, New Jersey, experiences a minor temperature shift with the start of June, with average high-temperatures moving from an agreeable 69.6°F (20.9°C) in May to a moderately hot 77.5°F (25.3°C). Weather in June »Weather in July
July, the same as June, is a moderately hot summer month in Mendham, New Jersey, with an average temperature ranging between min 64.8°F (18.2°C) and max 83.7°F (28.7°C). July, with an average high of 83.7°F (28.7°C) and a low of 64.8°F (18.2°C), signifies the warmest month of the year. During July, the heat index is estimated at a hot 91.4°F (33°C). Weather in July »Weather in August
The last month of the summer, August, is another warm month in Mendham, New Jersey, with an average temperature varying between 63°F (17.2°C) and 81.3°F (27.4°C). The transition from July to August brings an average high-temperature of a still warm 81.3°F (27.4°C), barely different from July's 83.7°F (28.7°C). Weather in August »Weather in September
September, the first month of the autumn in Mendham, is also a moderately hot month, with an average temperature fluctuating between 56.8°F (13.8°C) and 74.5°F (23.6°C). The arrival of September is marked by a minor reduction in average high-temperature, sliding from 81.3°F (27.4°C) in August to a still moderately hot 74.5°F (23.6°C). Weather in September »Weather in October
October, the same as September, is another enjoyable autumn month in Mendham, New Jersey, with an average temperature varying between 47.1°F (8.4°C) and 62.2°F (16.8°C). October brings a minor decrease, with the average high-temperature reducing from a warm 74.5°F (23.6°C) in September to an enjoyable 62.2°F (16.8°C). Weather in October »Weather in November
The last month of the autumn, November, is another cool month in Mendham, New Jersey, with an average temperature fluctuating between 36°F (2.2°C) and 50.4°F (10.2°C). The transition into November involves a decrease in the average high-temperature, falling from an enjoyable 62.2°F (16.8°C) in October to a fresh 50.4°F (10.2°C). Weather in November »Weather in December
The first month of the winter, December, is still a cold month in Mendham, New Jersey, with temperature in the range of an average high of 41°F (5°C) and an average low of 29.3°F (-1.5°C). The transition into December is accompanied by a temperature decrease, with the average high-temperature shifting from a cool 50.4°F (10.2°C) in November to an icy 41°F (5°C). Weather in December »Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature
Mendham, NJ
The warmest month (with the highest average high temperature) is July (83.7°F).
The month with the lowest average high temperature is January (35.1°F).
The month with the highest average low temperature is July (64.8°F).
The coldest month (with the lowest average low temperature) is January (22.3°F).
Average pressure
Mendham, NJ
- Average pressure in January:
30.07"Hg - Average pressure in February:
30.04"Hg - Average pressure in March:
30.06"Hg - Average pressure in April:
29.98"Hg - Average pressure in May:
30.01"Hg - Average pressure in June:
29.93"Hg
- Average pressure in July:
29.96"Hg - Average pressure in August:
29.99"Hg - Average pressure in September:
30.06"Hg - Average pressure in October:
30.03"Hg - Average pressure in November:
30.11"Hg - Average pressure in December:
30.08"Hg
The month with the highest atmospheric pressure is November (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed
Mendham, NJ
- Average wind speed in January:
8.1mph - Average wind speed in February:
8.1mph - Average wind speed in March:
8.3mph - Average wind speed in April:
8mph - Average wind speed in May:
6.4mph - Average wind speed in June:
6mph
- Average wind speed in July:
5.2mph - Average wind speed in August:
5.1mph - Average wind speed in September:
5.7mph - Average wind speed in October:
6.7mph - Average wind speed in November:
7mph - Average wind speed in December:
7.5mph
The windiest month (with the highest average wind speed) is March (8.3mph).
The calmest month (with the lowest average wind speed) is August (5.1mph).
Average humidity
Mendham, NJ
The months with the highest relative humidity are February and October (80%).
The month with the lowest relative humidity is April (75%).
Average rainfall
Mendham, NJ
- Average rainfall in January:
2.24" - Average rainfall in February:
2.24" - Average rainfall in March:
2.76" - Average rainfall in April:
2.91" - Average rainfall in May:
3.11" - Average rainfall in June:
2.76"
- Average rainfall in July:
3.31" - Average rainfall in August:
2.91" - Average rainfall in September:
1.85" - Average rainfall in October:
3.03" - Average rainfall in November:
2.6" - Average rainfall in December:
3.39"
The wettest month (with the highest rainfall) is December (3.39").
The driest month (with the least rainfall) is September (1.85").
Average rainfall days
Mendham, NJ
- Average rainfall days in January:
8.9 days - Average rainfall days in February:
10.2 days - Average rainfall days in March:
13.1 days - Average rainfall days in April:
16.4 days - Average rainfall days in May:
17.3 days - Average rainfall days in June:
16.8 days
- Average rainfall days in July:
17.3 days - Average rainfall days in August:
15.5 days - Average rainfall days in September:
12.9 days - Average rainfall days in October:
13.9 days - Average rainfall days in November:
9.4 days - Average rainfall days in December:
10.9 days
The months with the highest number of rainy days are May and July (17.3 days).
The month with the least rainy days is January (8.9 days).
Average snowfall
Mendham, NJ
- Average snowfall in January:
2.91" - Average snowfall in February:
3.5" - Average snowfall in March:
4.49" - Average snowfall in April:
0.28" - Average snowfall in May:
0.55" - Average snowfall in June:
0"
The month with the highest snowfall is March (4.49").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days
Mendham, NJ
- Average snowfall days in January:
8.3 days - Average snowfall days in February:
8.1 days - Average snowfall days in March:
5.8 days - Average snowfall days in April:
0.8 days - Average snowfall days in May:
0.2 days - Average snowfall days in June:
0 days
- Average snowfall days in July:
0 days - Average snowfall days in August:
0 days - Average snowfall days in September:
0 days - Average snowfall days in October:
0.1 days - Average snowfall days in November:
1.2 days - Average snowfall days in December:
4 days
The month with the highest number of snowfall days is January (8.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight / Average sunshine
Mendham, NJ
- Average daylight in January:
9h and 36min - Average daylight in February:
10h and 42min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 18min - Average daylight in May:
14h and 30min - Average daylight in June:
15h and 6min
- Average daylight in July:
14h and 48min - Average daylight in August:
13h and 42min - Average daylight in September:
12h and 30min - Average daylight in October:
11h and 6min - Average daylight in November:
9h and 54min - Average daylight in December:
9h and 18min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in January:
5h and 0min - Average sunshine in February:
4h and 36min - Average sunshine in March:
6h and 18min - Average sunshine in April:
8h and 12min - Average sunshine in May:
8h and 30min - Average sunshine in June:
9h and 36min
- Average sunshine in July:
10h and 30min - Average sunshine in August:
10h and 0min - Average sunshine in September:
8h and 42min - Average sunshine in October:
5h and 36min - Average sunshine in November:
5h and 36min - Average sunshine in December:
4h and 48min
The month with the most sunshine is July (Average sunshine: 10h and 30min).
The month with the least sunshine is February (Average sunshine: 4h and 36min).
Average sunshine days
Mendham, NJ
- Average sunshine days in January:
17 days - Average sunshine days in February:
12.8 days - Average sunshine days in March:
13.3 days - Average sunshine days in April:
11.8 days - Average sunshine days in May:
11.4 days - Average sunshine days in June:
11.5 days
- Average sunshine days in July:
12 days - Average sunshine days in August:
12.4 days - Average sunshine days in September:
15 days - Average sunshine days in October:
15.5 days - Average sunshine days in November:
17.6 days - Average sunshine days in December:
16.6 days
The month with the most sunshine days is November (17.6 days).
The month with the least sunshine days is May (11.4 days).
Average UV index
Mendham, NJ
The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January, February, March, November and December (UV index 2).
Average cloud cover
Mendham, NJ
The months with the most cloud cover are February and December (Cloud cover 49).
The month with the least cloud cover is July (Cloud cover 33).
Average visibility
Mendham, NJ
The months with the highest visibility are January, February, March, April, June, July, August, November and December (6mi).
The months with the lowest visibility are May, September and October (5mi).





