Climate and monthly weather forecastIselin, NJ
Climate and monthly weather forecast
Weather in January
January, like December, in Iselin, New Jersey, is a wintry winter month, with temperature in the range of an average high of 36.5°F (2.5°C) and an average low of 25.7°F (-3.5°C). January is the coldest month, with an average high-temperature of 36.5°F (2.5°C) and an average low-temperature of 25.7°F (-3.5°C). Weather in January »Weather in February
February, the last month of the winter in Iselin, is also a wintry month, with an average temperature fluctuating between 27.3°F (-2.6°C) and 39.2°F (4°C). February experiences an average high-temperature of a still cold 39.2°F (4°C), barely different from January's 36.5°F (2.5°C). Weather in February »Weather in March
March, the first month of the spring in Iselin, is a chilly month, with an average temperature fluctuating between 34.3°F (1.3°C) and 46.9°F (8.3°C). Entering March, Iselin notices a subtle temperature elevation, with the average high-temperature advancing from February's wintry 39.2°F (4°C) to a chilly 46.9°F (8.3°C). Weather in March »Weather in April
April in Iselin, New Jersey, is a moderate spring month, with an average temperature varying between 58.3°F (14.6°C) and 44.1°F (6.7°C). Iselin sees an increase in average high-temperatures during April, moving from a chilly 46.9°F (8.3°C) in March to a mild 58.3°F (14.6°C). Weather in April »Weather in May
May, the last month of the spring in Iselin, is a pleasant month, with an average temperature fluctuating between 68.2°F (20.1°C) and 54°F (12.2°C). The start of May signals an increase in the average high-temperature, moving from a moderate 58.3°F (14.6°C) in April to an agreeable 68.2°F (20.1°C). Weather in May »Weather in June
June, the first month of the summer in Iselin, is a moderately hot month, with an average temperature ranging between min 62.1°F (16.7°C) and max 76.8°F (24.9°C). June brings a slight elevation in the average high-temperature, transitioning from May's agreeable 68.2°F (20.1°C) to a moderately hot 76.8°F (24.9°C). Weather in June »Weather in July
July, the same as June, is another warm summer month in Iselin, New Jersey, with an average temperature fluctuating between 68.9°F (20.5°C) and 83.1°F (28.4°C). July is the month when Iselin sees the highest average temperatures, with a high of 83.1°F (28.4°C) and a low of 68.9°F (20.5°C). In July, the heat index is estimated at a tropical 89.6°F (32°C). Weather in July »Weather in August
August, the last month of the summer in Iselin, is also a moderately hot month, with an average temperature fluctuating between 81.9°F (27.7°C) and 68.4°F (20.2°C). Iselin, New Jersey, records an average high-temperature of a still moderately hot 81.9°F (27.7°C) in August, maintaining a close correlation with July's 83.1°F (28.4°C). Weather in August »Weather in September
The first month of the autumn, September, is also a moderately hot month in Iselin, New Jersey, with an average temperature fluctuating between 75.2°F (24°C) and 61.2°F (16.2°C). With the arrival of September, Iselin notices a mild change in the average high-temperature, sliding from August's moderately hot 81.9°F (27.7°C) to a still warm 75.2°F (24°C). Weather in September »Weather in October
October, like September, in Iselin, New Jersey, is another comfortable autumn month, with an average temperature varying between 63.3°F (17.4°C) and 50.9°F (10.5°C). The average high-temperature decreases in October, shifting from a moderately hot 75.2°F (24°C) in September to a comfortable 63.3°F (17.4°C). Weather in October »Weather in November
The last month of the autumn, November, is also a fresh month in Iselin, New Jersey, with temperature in the range of an average low of 39.7°F (4.3°C) and an average high of 51.3°F (10.7°C). Iselin observes a minor decrease in the average high-temperature with the arrival of November, falling from October's refreshing 63.3°F (17.4°C) to a fresh 51.3°F (10.7°C). Weather in November »Weather in December
December, the first month of the winter in Iselin, is also a wintry month, with temperature in the range of an average low of 32.9°F (0.5°C) and an average high of 42.4°F (5.8°C). December heralds a minor drop in average high-temperature, sliding from November's fresh 51.3°F (10.7°C) to an icy 42.4°F (5.8°C). Weather in December »Updated: Feb 13, 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
Iselin's coldest month, January, generally records average temperatures ranging from a high of 36.5°F (2.5°C) to a low of 25.7°F (-3.5°C).
Throughout the year, in Iselin, New Jersey, there are 110.2 rainfall days, and 8.9" (226mm) of precipitation is accumulated.
Months with snowfall are January through April, November and December.
Throughout the year, in Iselin, New Jersey, there are 14.5 snowfall days, and 1.85" (47mm) of snow is accumulated.
The months with the lowest UV index in Iselin are January through March, November and December, with an average maximum UV index of 2.
The most humid month is February, with an average relative humidity of 77%.
February has the least sunshine of the year, with an average of 4.7h of sunshine.
The month with the most snowfall in Iselin is March, when snow falls for 3 days and typically aggregates up to 0.83" (21mm) of snow.
On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts in Iselin, New Jersey, 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.
May through October are months without snowfall in Iselin, New Jersey.
With an average of 15h and 0min of daylight, June has the longest days of the year in Iselin, New Jersey.
The months with the highest UV index in Iselin, New Jersey, are June through August, with an average maximum UV index of 6.
Iselin's temperatures tend to reach their peak averages in July, with a high of 83.1°F (28.4°C) and a low of 68.9°F (20.5°C).
The month with the most rainfall in Iselin, New Jersey, is July, when the rain falls for 12.7 days and typically aggregates up to 1.22" (31mm) of precipitation.
The month with the most sunshine in Iselin, New Jersey, is July, with an average of 10.6h of sunshine.
August is the least humid month in Iselin, with an average relative humidity of 72%.
September is the month with the least rainfall. Rain falls for 9.6 days and accumulates 0.39" (10mm) of precipitation.
December has the shortest days of the year, with an average of 9h and 18min of daylight.
Average temperature
Iselin, NJ
The warmest month (with the highest average high temperature) is July (83.1°F).
The month with the lowest average high temperature is January (36.5°F).
The month with the highest average low temperature is July (68.9°F).
The coldest month (with the lowest average low temperature) is January (25.7°F).
Average pressure
Iselin, 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
Iselin, NJ
- Average wind speed in January:
9.6mph - Average wind speed in February:
9.4mph - Average wind speed in March:
9.6mph - Average wind speed in April:
9mph - Average wind speed in May:
7.5mph - Average wind speed in June:
6.9mph
- Average wind speed in July:
6.3mph - Average wind speed in August:
6.4mph - Average wind speed in September:
7mph - Average wind speed in October:
8.2mph - Average wind speed in November:
8.6mph - Average wind speed in December:
8.9mph
The windiest months (with the highest average wind speed) are January and March (9.6mph).
The calmest month (with the lowest average wind speed) is July (6.3mph).
Average humidity
Iselin, NJ
The month with the highest relative humidity is February (77%).
The month with the lowest relative humidity is August (72%).
Average rainfall
Iselin, NJ
- Average rainfall in January:
0.51" - Average rainfall in February:
0.55" - Average rainfall in March:
0.63" - Average rainfall in April:
0.63" - Average rainfall in May:
0.94" - Average rainfall in June:
0.71"
- Average rainfall in July:
1.22" - Average rainfall in August:
0.98" - Average rainfall in September:
0.39" - Average rainfall in October:
0.79" - Average rainfall in November:
0.71" - Average rainfall in December:
0.83"
The wettest month (with the highest rainfall) is July (1.22").
The driest month (with the least rainfall) is September (0.39").
Average rainfall days
Iselin, NJ
- Average rainfall days in January:
4.9 days - Average rainfall days in February:
6.3 days - Average rainfall days in March:
9 days - Average rainfall days in April:
10.4 days - Average rainfall days in May:
12.2 days - Average rainfall days in June:
11.3 days
- Average rainfall days in July:
12.7 days - Average rainfall days in August:
12.2 days - Average rainfall days in September:
9.6 days - Average rainfall days in October:
8.6 days - Average rainfall days in November:
5.7 days - Average rainfall days in December:
7.3 days
The month with the highest number of rainy days is July (12.7 days).
The month with the least rainy days is January (4.9 days).
Average snowfall
Iselin, NJ
The month with the highest snowfall is March (0.83").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days
Iselin, NJ
- Average snowfall days in January:
3.8 days - Average snowfall days in February:
4.2 days - Average snowfall days in March:
3 days - Average snowfall days in April:
0.3 days - Average snowfall days in May:
0 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:
0.3 days - Average snowfall days in December:
2.8 days
The month with the highest number of snowfall days is February (4.2 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight / Average sunshine
Iselin, 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 12min - Average sunshine in February:
4h and 42min - Average sunshine in March:
6h and 24min - Average sunshine in April:
8h and 24min - Average sunshine in May:
8h and 48min - Average sunshine in June:
9h and 54min
- Average sunshine in July:
10h and 36min - Average sunshine in August:
10h and 24min - Average sunshine in September:
8h and 54min - Average sunshine in October:
5h and 48min - 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 36min).
The month with the least sunshine is February (Average sunshine: 4h and 42min).
Average sunshine days
Iselin, NJ
- Average sunshine days in January:
22.6 days - Average sunshine days in February:
18.6 days - Average sunshine days in March:
18.7 days - Average sunshine days in April:
17.3 days - Average sunshine days in May:
15.8 days - Average sunshine days in June:
15.4 days
- Average sunshine days in July:
14.8 days - Average sunshine days in August:
15.7 days - Average sunshine days in September:
17.9 days - Average sunshine days in October:
19.8 days - Average sunshine days in November:
22.4 days - Average sunshine days in December:
21.3 days
The month with the most sunshine days is January (22.6 days).
The month with the least sunshine days is July (14.8 days).
Average UV index
Iselin, 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
Iselin, NJ
The months with the most cloud cover are February, March and December (Cloud cover 47).
The months with the least cloud cover are July and August (Cloud cover 30).
Average visibility
Iselin, NJ
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
