July weather forecastHyannis, MA

July

Weather in July

As the heart of the summer, July boasts the highest temperatures of the year in Hyannis. The sea temperature reaches its annual peak of 65.8°F (18.8°C), perfectly suited for beach-related activities. An extended duration of sunshine hours ensures a high UV index. However, this increase is counterbalanced by a drop in cloud cover percentage, keeping weather patterns predictable. The rainfall tendencies decrease in July, exhibiting some of the best weather conditions of the year.

Temperature

Hyannis in July denotes a subtle temperature transition, adjusting from an average high of a refreshing 63.9°F (17.7°C) in June to an agreeable 72°F (22.2°C). In Hyannis, July nights experience a modest descent in temperature from daily peaks, cooling down to an average of 67.6°F (19.8°C).

Humidity

July is the most humid month, with an average relative humidity of 84%.

Rainfall

In July, the rain falls for 15.1 days. Throughout July, 2.05" (52mm) of precipitation is accumulated. In Hyannis, Massachusetts, during the entire year, the rain falls for 157.2 days and collects up to 31.77" (807mm) of precipitation.

Snowfall

May through November are months without snowfall.

Ocean temperature

In July, the average ocean temperature is 65.8°F (18.8°C).
Note: Swimming in 65.8°F (18.8°C) does not offer a pleasant experience for most individuals. The act of controlling one's breathing becomes progressively difficult as the water temperature goes under 69.8°F (21°C).

Daylight

The average length of the day in July is 14h and 50min.
On the first day of July, sunrise is at 5:10 am and sunset at 8:19 pm. On the last day of the month, sunrise is at 5:35 am and sunset at 7:59 pm EDT.

Sunshine

The average sunshine in July is 10.6h.

UV index

July and August, with an average maximum UV index of 6, are months with the highest UV index. A UV Index value of 6 to 7 symbolizes a high threat to health from unsafe exposure to UV radiation for average individuals.
Note: The UV index of 6 during July leads to these advisories:
Avert overexposure. Light-skinned people might experience burning in less than 20 minutes. The Sun's UV radiation is most potent between 10 a.m. and 4 p.m. Try to limit direct exposure to the Sun during this period. During bright days, sunglasses that offer UVA and UVB defense are recommended.

Updated: Jun 4, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

The average high-temperature, in July, in Hyannis, is 72°F (22.2°C), while the average low-temperature is 67.6°F (19.8°C).

With an average relative humidity of 84%, July is the most humid month.

The average relative humidity in July is 84%.

In July, the rain falls for 15.1 days. Throughout July, 2.05" (52mm) of precipitation is accumulated.

In Hyannis, snow does not fall in May through November.

In July, the average ocean temperature is 65.8°F (18.8°C). For swimming, a surface water temperature of 65.8°F (18.8°C) is not enjoyable for the majority. It is not considered safe, as controlling breathing becomes progressively more difficult as water temperature decreases below 69.8°F (21°C).

In Hyannis, the average day length in July is 14h and 50min.

In July, on the first day of the month, sunrise is at 5:10 am and sunset at 8:19 pm. On the last day of the month, sunrise is at 5:35 am and sunset at 7:59 pm EDT.

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

The months with the highest UV index in Hyannis are July and August, with an average maximum UV index of 6.

The average daily maximum UV index in July is 6. A UV Index estimate of 6 to 7 represents a high health risk from unsafe exposure to Sun's UV rays.

Today

Tomorrow

Long-term

Year J F M A M J July A S O N D

Jun

July

Aug

Average high temperature

63.9°F

72°F

72.5°F

Average low temperature

Average pressure

Average wind speed

Average max. wind speed

12.1mph

11.4mph

11.3mph

Average wind speed gusts

Average humidity

Average rainfall

Average rainfall days

12.9

15.1

12.4

Average snowfall

Average snowfall days

Average sea temperature

Average daylight

Average sunshine

Average sunshine days

15.1

14.9

17.7

Average UV index

Average cloud cover

Average visibility

Average temperature in July
Hyannis, MA

Average high temperature in July: 72°F

The warmest month (with the highest average high temperature) is August (72.5°F).
The month with the lowest average high temperature is January (38.3°F).

Average low temperature in July: 67.6°F

The month with the highest average low temperature is August (68.2°F).
The coldest month (with the lowest average low temperature) is January (30.4°F).

Average pressure in July
Hyannis, MA

Average pressure in July: 29.96"Hg

The month with the highest atmospheric pressure is November (30.06"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).

Average wind speed in July
Hyannis, MA

Average wind speed in July: 10.7mph

The windiest month (with the highest average wind speed) is January (16.5mph).
The calmest month (with the lowest average wind speed) is August (10.6mph).

Average humidity in July
Hyannis, MA

Average humidity in July: 84%

The month with the highest relative humidity is July (84%).
The month with the lowest relative humidity is November (74%).

Average rainfall in July
Hyannis, MA

Average rainfall in July: 2.05"

The wettest month (with the highest rainfall) is October (3.7").
The driest month (with the least rainfall) is August (1.73").

Average rainfall days in July
Hyannis, MA

Average rainfall days in July: 15.1 days

The month with the highest number of rainy days is April (15.8 days).
The month with the least rainy days is February (10.3 days).

Average snowfall in July
Hyannis, MA

Average snowfall in July: 0"

The month with the highest snowfall is March (1.93").
The months with the least snowfall are May, June, July, August, September, October and November (0").

Average snowfall days in July
Hyannis, MA

Average snowfall days in July: 0 days

The month with the highest number of snowfall days is February (7.1 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).

Average sea temperature in July
Hyannis, MA

Average sea temperature in July: 65.8°F

The best month for swimming (with the highest average sea temperature) is August (67.5°F).
The coldest month (with the lowest average sea temperature) is March (39°F).

Average daylight in July /
Average sunshine in July
Hyannis, MA

Average daylight in July: 14h and 48min

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 12min).

Average sunshine in July: 10h and 36min

The month with the most sunshine is August (Average sunshine: 10h and 48min).
The month with the least sunshine is December (Average sunshine: 4h and 36min).

Average sunshine days in July
Hyannis, MA

Average sunshine days in July: 14.9 days

The month with the most sunshine days is August (17.7 days).
The month with the least sunshine days is February (11.4 days).

Average UV index in July
Hyannis, MA

Average UV index in July: 6

The months with the highest UV index are 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
Hyannis, MA

Average cloud cover in July: 29

The months with the most cloud cover are February and December (Cloud cover 50).
The month with the least cloud cover is August (Cloud cover 27).

Average visibility in July
Hyannis, MA

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).