July weather forecast
Stony Brook, NY

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Weather in July

July in Stony Brook, New York, is a moderately hot summer month, with an average temperature fluctuating between 71.1°F (21.7°C) and 79.2°F (26.2°C).

Temperature

The temperatures reach their highest averages in July, with highs of 79.2°F (26.2°C) and lows of 71.1°F (21.7°C).

Humidity

In Stony Brook, New York, the average relative humidity in July is 76%.

Rainfall

In Stony Brook, in July, it is raining for 16.5 days, with typically 3.54" (90mm) of accumulated precipitation. Throughout the year, there are 146.8 rainfall days, and 33.78" (858mm) of precipitation is accumulated.

Snowfall

In Stony Brook, snow does not fall in April through September.

Ocean temperature

In Stony Brook, the average seawater temperature in July is 72.1°F (22.3°C).
Note: Every individual's cold threshold differs, but factors like today's sunshine, wind, and temperature can tip the scales for a delightful swim in 72.1°F (22.3°C) waters. For reference, Olympians swim in waters of 77°F (25°C) to 82.4°F (28°C).

Daylight

In July, the average length of the day is 14h and 46min.
On the first day of July, sunrise is at 5:24 am and sunset at 8:28 pm. On the last day of the month, sunrise is at 5:48 am and sunset at 8:09 pm EDT.

Sunshine

With an average of 10.6h of sunshine, July has the most sunshine of the year.

UV index

The months with the highest UV index are June through August, with an average maximum UV index of 6. A UV Index reading of 6 to 7 represents a high threat to health from exposure to the Sun's UV rays for ordinary individuals.
Note: An average maximum UV index of 6 in July leads to these recommendations:
Use protective steps and abide by sun safety guidelines. Safeguarding against skin and eye harm is necessary. Stay in the shade and limit direct sun exposure between 10 a.m. and 4 p.m., when UV radiation is at its strongest. Remember, however, that not all shade structures provide full sun protection. A wide-brimmed hat is a staple for defending the face, eyes, ears, and neck from the Sun. Notice! The Sun's UV exposure elevates with sand and water reflections.
Updated: Aug 25, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What is the hottest time of year?

During the warmest month in Stony Brook, July, temperatures average a high of 79.2°F (26.2°C) and a low of 71.1°F (21.7°C).

What are the temperatures in July?

The high-temperature during July is 79.2°F (26.2°C) and the low-temperature is 71.1°F (21.7°C).

What is the average humidity in July in Stony Brook?

In Stony Brook, the average relative humidity in July is 76%.

How many days does it rain in July?

In Stony Brook, in July, during 16.5 rainfall days, 3.54" (90mm) of precipitation is typically accumulated.

When it does not snow?

April through September are months without snowfall.

What is the ocean temperature in July?

In Stony Brook, in July, the average water temperature is 72.1°F (22.3°C). A person's cold intolerance, with sunshine, wind, and air temperature, are essential factors for enjoying swimming in 72.1°F (22.3°C) water.

How many hours of daylight does Stony Brook have in July?

In July, the average day length is 14h and 46min.

When are sunrise and sunset in July?

On the first day of July in Stony Brook, sunrise is at 5:24 am and sunset at 8:28 pm. On the last day of the month, sunrise is at 5:48 am and sunset at 8:09 pm EDT.

What month has the most sunshine?

The month with the most sunshine in Stony Brook is July, with an average of 10.6h of sunshine.

How long on average sun shines in July?

In Stony Brook, the average sunshine duration in July is 10.6h.

What is the month with the highest UV index?

The months with the highest UV index are June through August, with an average maximum UV index of 6.

What is the UV index intensity in July?

In July, the average daily maximum UV index is 6. A UV Index reading of 6 to 7 represents a high health threat from exposure to the Sun's UV radiation.
Average humidity
Average rainfall days
Average snowfall
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in July
Stony Brook, NY

Average temperature in July - Stony Brook, NY
  • Average high temperature in July: 79.2°F

The warmest month (with the highest average high temperature) is July (79.2°F).
The month with the lowest average high temperature is January (37.6°F).

  • Average low temperature in July: 71.1°F

The months with the highest average low temperature are July and August (71.1°F).
The coldest month (with the lowest average low temperature) is January (29.1°F).

Average pressure in July
Stony Brook, NY

Average pressure in July - Stony Brook, NY
  • Average pressure in July: 29.95"Hg

The month with the highest atmospheric pressure is November (30.09"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).

Average wind speed in July
Stony Brook, NY

Average wind speed in July - Stony Brook, NY
  • Average wind speed in July: 8.3mph

The windiest month (with the highest average wind speed) is January (12.9mph).
The calmest month (with the lowest average wind speed) is July (8.3mph).

Average humidity in July
Stony Brook, NY

Average humidity in July - Stony Brook, NY
  • Average humidity in July: 76%

The months with the highest relative humidity are May and June (77%).
The month with the lowest relative humidity is November (71%).

Average rainfall in July
Stony Brook, NY

Average rainfall in July - Stony Brook, NY
  • Average rainfall in July: 3.54"

The wettest month (with the highest rainfall) is December (3.58").
The driest month (with the least rainfall) is January (2.05").

Average rainfall days in July
Stony Brook, NY

Average rainfall days in July - Stony Brook, NY
  • Average rainfall days in July: 16.5 days

The month with the highest number of rainy days is July (16.5 days).
The month with the least rainy days is January (6.8 days).

Average snowfall in July
Stony Brook, NY

Average snowfall in July - Stony Brook, NY
  • Average snowfall in July: 0"

The month with the highest snowfall is March (2.13").
The months with the least snowfall are April, May, June, July, August and September (0").

Average snowfall days in July
Stony Brook, NY

Average snowfall days in July - Stony Brook, NY
  • Average snowfall days in July: 0 days

The month with the highest number of snowfall days is February (4.4 days).
The months with the least snowfall days are May, June, July, August and September (0 days).

Average sea temperature in July
Stony Brook, NY

Average sea temperature in July - Stony Brook, NY
  • Average sea temperature in July: 72.1°F

The best month for swimming (with the highest average sea temperature) is August (74°F).
The coldest month (with the lowest average sea temperature) is February (39.7°F).

Average daylight in July /
Average sunshine in July
Stony Brook, NY

Average daylight in July / Average sunshine in July - Stony Brook, NY
  • Average daylight in July: 14h and 5min

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 July: 10h and 4min

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 in July
Stony Brook, NY

Average sunshine days in July - Stony Brook, NY
  • Average sunshine days in July: 13 days

The month with the most sunshine days is November (20.5 days).
The month with the least sunshine days is July (13 days).

Average UV index in July
Stony Brook, NY

Average UV index in July - Stony Brook, NY
  • Average UV index in July: 6

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 in July
Stony Brook, NY

Average cloud cover in July - Stony Brook, NY
  • Average cloud cover in July: 30

The month with the most cloud cover is December (Cloud cover 49).
The month with the least cloud cover is August (Cloud cover 28).

Average visibility in July
Stony Brook, NY

Average visibility in July - Stony Brook, NY
  • Average visibility in July: 6mi

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).

Stony Brook, New York, USA

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