Climate and monthly weather forecastMountainside, NJ
Climate and monthly weather forecast
Weather in January
January, like December, in Mountainside, New Jersey, is another cold winter month, with an average temperature varying between 36°F (2.2°C) and 23.9°F (-4.5°C). The coldest period tends to be January, when average temperatures fluctuate between a high of 36°F (2.2°C) and a low of 23.9°F (-4.5°C). Weather in January »Weather in February
The last month of the winter, February, is also a wintry month in Mountainside, New Jersey, with an average temperature fluctuating between 25.7°F (-3.5°C) and 39.2°F (4°C). February begins with an average high-temperature of a still cold 39.2°F (4°C), reflecting close similarity to the preceding month. Weather in February »Weather in March
March, the first month of the spring in Mountainside, is a chilly month, with an average temperature varying between 47.3°F (8.5°C) and 32.9°F (0.5°C). March's arrival sees a mild rise in the average high-temperature, transitioning from February's cold 39.2°F (4°C) to a chilly 47.3°F (8.5°C). Weather in March »Weather in April
April is a moderate spring month in Mountainside, New Jersey, with an average temperature fluctuating between 43.3°F (6.3°C) and 59°F (15°C). A rise in the average high-temperature is observed during April, moving from a chilly 47.3°F (8.5°C) in March to a refreshing 59°F (15°C). Weather in April »Weather in May
The last month of the spring, May, is a pleasant month in Mountainside, New Jersey, with an average temperature varying between 69.3°F (20.7°C) and 52.9°F (11.6°C). With the arrival of May, the average high-temperature transitions from a moderate 59°F (15°C) in April to an agreeable 69.3°F (20.7°C). Weather in May »Weather in June
June, the first month of the summer in Mountainside, is a warm month, with temperature in the range of an average low of 60.6°F (15.9°C) and an average high of 77.5°F (25.3°C). The coming of June brings a minor shift in Mountainside's weather, with average high-temperatures adjusting from May's agreeable 69.3°F (20.7°C) to a warm 77.5°F (25.3°C). Weather in June »Weather in July
July, like June, in Mountainside, New Jersey, is another warm summer month, with an average temperature varying between 84.2°F (29°C) and 67.5°F (19.7°C). July is the warmest month, with an average high-temperature of 84.2°F (29°C) and an average low-temperature of 67.5°F (19.7°C). July's mean heat index is calculated to be a hot 91.4°F (33°C). Weather in July »Weather in August
August, the last month of the summer in Mountainside, is also a moderately hot month, with an average temperature fluctuating between 82°F (27.8°C) and 66.2°F (19°C). Shifting into August, Mountainside records an average high-temperature of a still moderately hot 82°F (27.8°C), presenting minor fluctuations compared to the previous month. Weather in August »Weather in September
The first month of the autumn, September, is still a warm month in Mountainside, New Jersey, with an average temperature varying between 75.4°F (24.1°C) and 59.4°F (15.2°C). The transition into September is accompanied by a slight temperature decrease, with the average high-temperature shifting from 82°F (27.8°C) in August to a still moderately hot 75.4°F (24.1°C). Weather in September »Weather in October
October, the same as September, is another comfortable autumn month in Mountainside, New Jersey, with an average temperature varying between 49.1°F (9.5°C) and 63.1°F (17.3°C). A shift in the average high-temperature occurs in October, reducing from a warm 75.4°F (24.1°C) in September to a comfortable 63.1°F (17.3°C). Weather in October »Weather in November
The last month of the autumn, November, is also a fresh month in Mountainside, New Jersey, with an average temperature fluctuating between 38.1°F (3.4°C) and 51.1°F (10.6°C). Mountainside's November weather features a mild decline in high-temperatures, reducing from an enjoyable 63.1°F (17.3°C) in October to a fresh 51.1°F (10.6°C). Weather in November »Weather in December
The first month of the winter, December, is also a wintry month in Mountainside, New Jersey, with an average temperature varying between 42.3°F (5.7°C) and 31.1°F (-0.5°C). With the onset of December, Mountainside's average high-temperature slightly adjusts, moderately receding from November's fresh 51.1°F (10.6°C) to a cold 42.3°F (5.7°C). Weather in December »Updated: Jul 22, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
The month of January sees the average lowest temperatures, reaching 36°F (2.2°C) at the peak and 23.9°F (-4.5°C) at the low.
In Mountainside, during the entire year, the rain falls for 160.7 days and collects up to 30.12" (765mm) of precipitation.
Months with snowfall are January through May, October through December.
Throughout the year, there are 25.4 snowfall days, and 10.31" (262mm) of snow is accumulated.
The months with the lowest UV index in Mountainside are January through March, November and December, with an average maximum UV index of 2.
The months with the highest humidity are February, October and December, with an average relative humidity of 78%.
With an average of 4.6h of sunshine, February has the least sunshine of the year.
The month with the most snowfall is March, when snow falls for 5 days and typically aggregates up to 3.23" (82mm) of snow.
On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts, and the time zone changes from EST to EDT. Daylight Saving Time ends Sunday, November 3. 2024, at 2:00 am, and the time zone reverts from EDT to EST.
April and August, with an average relative humidity of 73%, are the least humid months.
June through September are months without snowfall.
With an average of 15h and 0min of daylight, June has the longest days of the year in Mountainside.
June through August, with an average maximum UV index of 6, are months with the highest UV index.
July is the month when Mountainside's temperatures reach their peak, with averages of 84.2°F (29°C) and lows of 67.5°F (19.7°C).
July has the most sunshine of the year, with an average of 10.5h of sunshine.
The month with the least rainfall is September, when the rain falls for 12.9 days and typically collects 1.69" (43mm) of precipitation.
December is the month with the most rainfall. Rain falls for 11.5 days and accumulates 3.19" (81mm) of precipitation.
December has the shortest days of the year, with an average of 9h and 18min of daylight.
Average temperature
Mountainside, NJ
The warmest month (with the highest average high temperature) is July (84.2°F).
The month with the lowest average high temperature is January (36°F).
The month with the highest average low temperature is July (67.5°F).
The coldest month (with the lowest average low temperature) is January (23.9°F).
Average pressure
Mountainside, 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:
29.98"Hg - Average pressure in September:
30.05"Hg - Average pressure in October:
30.02"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
Mountainside, NJ
- Average wind speed in January:
8.8mph - Average wind speed in February:
8.7mph - Average wind speed in March:
8.9mph - Average wind speed in April:
8.5mph - Average wind speed in May:
7mph - Average wind speed in June:
6.5mph
- Average wind speed in July:
5.7mph - Average wind speed in August:
5.7mph - Average wind speed in September:
6.3mph - Average wind speed in October:
7.3mph - Average wind speed in November:
7.8mph - Average wind speed in December:
8.1mph
The windiest month (with the highest average wind speed) is March (8.9mph).
The calmest months (with the lowest average wind speed) are July and August (5.7mph).
Average humidity
Mountainside, NJ
The months with the highest relative humidity are February, October and December (78%).
The months with the lowest relative humidity are April and August (73%).
Average rainfall
Mountainside, NJ
- Average rainfall in January:
1.97" - Average rainfall in February:
2.24" - Average rainfall in March:
2.64" - Average rainfall in April:
2.36" - Average rainfall in May:
2.8" - Average rainfall in June:
2.4"
- Average rainfall in July:
3.03" - Average rainfall in August:
2.6" - Average rainfall in September:
1.69" - Average rainfall in October:
2.83" - Average rainfall in November:
2.36" - Average rainfall in December:
3.19"
The wettest month (with the highest rainfall) is December (3.19").
The driest month (with the least rainfall) is September (1.69").
Average rainfall days
Mountainside, NJ
- Average rainfall days in January:
9.5 days - Average rainfall days in February:
10.5 days - Average rainfall days in March:
12.7 days - Average rainfall days in April:
15.4 days - Average rainfall days in May:
16.3 days - Average rainfall days in June:
16.4 days
- Average rainfall days in July:
16.5 days - Average rainfall days in August:
15.6 days - Average rainfall days in September:
12.9 days - Average rainfall days in October:
13.4 days - Average rainfall days in November:
10 days - Average rainfall days in December:
11.5 days
The month with the highest number of rainy days is July (16.5 days).
The month with the least rainy days is January (9.5 days).
Average snowfall
Mountainside, NJ
- Average snowfall in January:
2.09" - Average snowfall in February:
2.87" - Average snowfall in March:
3.23" - Average snowfall in April:
0.2" - Average snowfall in May:
0.24" - Average snowfall in June:
0"
The month with the highest snowfall is March (3.23").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days
Mountainside, NJ
- Average snowfall days in January:
7.3 days - Average snowfall days in February:
7.3 days - Average snowfall days in March:
5 days - Average snowfall days in April:
0.6 days - Average snowfall days in May:
0.1 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:
0.9 days - Average snowfall days in December:
4.1 days
The months with the highest number of snowfall days are January and February (7.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight / Average sunshine
Mountainside, NJ
- Average daylight in January:
9h and 42min - 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 0min
- Average daylight in July:
14h and 42min - 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 0min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in January:
5h and 6min - 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 36min - Average sunshine in June:
9h and 42min
- Average sunshine in July:
10h and 30min - Average sunshine in August:
10h and 6min - Average sunshine in September:
8h and 42min - Average sunshine in October:
5h and 42min - Average sunshine in November:
5h and 36min - Average sunshine in December:
4h and 54min
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
Mountainside, NJ
- Average sunshine days in January:
17.3 days - Average sunshine days in February:
13.7 days - Average sunshine days in March:
14 days - Average sunshine days in April:
12.4 days - Average sunshine days in May:
12.6 days - Average sunshine days in June:
11.4 days
- Average sunshine days in July:
12.8 days - Average sunshine days in August:
13.3 days - Average sunshine days in September:
14.5 days - Average sunshine days in October:
15.5 days - Average sunshine days in November:
18.4 days - Average sunshine days in December:
15.8 days
The month with the most sunshine days is November (18.4 days).
The month with the least sunshine days is June (11.4 days).
Average UV index
Mountainside, NJ
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, March, November and December (UV index 2).
Average cloud cover
Mountainside, NJ
The months with the most cloud cover are February, March and December (Cloud cover 48).
The months with the least cloud cover are July and August (Cloud cover 32).
Average visibility
Mountainside, NJ
The months with the highest visibility are January, February, March, April, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is May (5mi).
