August weather forecastPortsmouth, RI
August
Weather in August
August maintains the summer sizzle in Portsmouth with little to no drop in temperature from July. Rainfall sees a minute rise compared to July, but overall, the fair weather continues to prevail. The approaching September brings a relief in the form of a moderate drop in temperature. The days continue to be bathed in sunlight, ensuring enough time for beach-goers to soak up the summer sun. However, humidity remains elevated, typical of the seaside town's climatic rhythm.Temperature
With the transition into August, Portsmouth notes an average high-temperature of a still warm 77.7°F (25.4°C), closely resembling July. During the month of August, an average temperature of 65.7°F (18.7°C) is noted during the nights.Humidity
The average relative humidity in August is 78%.Rainfall
In August, the rain falls for 11.8 days. Throughout August, 2.09" (53mm) of precipitation is accumulated. In Portsmouth, during the entire year, the rain falls for 148.1 days and collects up to 29.65" (753mm) of precipitation.Snowfall
In Portsmouth, snow does not fall in April, June through October.Daylight
In Portsmouth, the average length of the day in August is 13h and 48min.On the first day of August, sunrise is at 5:40 am and sunset at 8:02 pm. On the last day of the month, sunrise is at 6:10 am and sunset at 7:19 pm EDT.
Sunshine
The month with the most sunshine in Portsmouth is August, with an average of 10.5h of sunshine.UV index
The months with the highest UV index are June through August, with an average maximum UV index of 6. A UV Index of 6 to 7 symbolizes a high health hazard from exposure to the Sun's UV radiation for the average person.Note: The daily high UV index of 6 in August translates into this advice:
Skirt overexposure. People with light complexions might get scorched in under 20 minutes. Be aware that the sun's UV radiation is strongest between 10 a.m. and 4 p.m. and try to reduce direct sun exposure during this period as much as possible. Prioritize a wide-brim hat for comprehensive sun defense for your face, neck, eyes, and ears.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in August
Portsmouth, RI
- Average high temperature in August: 77.7°F
The warmest month (with the highest average high temperature) is July (78.3°F).
The month with the lowest average high temperature is January (36.1°F).
- Average low temperature in August: 65.7°F
The month with the highest average low temperature is July (66.7°F).
The coldest month (with the lowest average low temperature) is January (26.4°F).
Average pressure in August
Portsmouth, RI
- Average pressure in August: 29.98"Hg
The month with the highest atmospheric pressure is November (30.07"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in August
Portsmouth, RI
- Average wind speed in August: 8.1mph
The windiest month (with the highest average wind speed) is January (12.1mph).
The calmest month (with the lowest average wind speed) is August (8.1mph).
Average humidity in August
Portsmouth, RI
- Average humidity in August: 78%
The month with the highest relative humidity is June (81%).
The month with the lowest relative humidity is March (73%).
Average rainfall in August
Portsmouth, RI
- Average rainfall in August: 2.09"
The wettest month (with the highest rainfall) is October (3.27").
The driest month (with the least rainfall) is September (1.42").
Average rainfall days in August
Portsmouth, RI
- Average rainfall days in August: 11.8 days
The month with the highest number of rainy days is April (15.6 days).
The month with the least rainy days is January (8.3 days).
Average snowfall in August
Portsmouth, RI
- Average snowfall in August: 0"
The month with the highest snowfall is February (2.76").
The months with the least snowfall are April, June, July, August, September and October (0").
Average snowfall days in August
Portsmouth, RI
- Average snowfall days in August: 0 days
The month with the highest number of snowfall days is January (6.6 days).
The months with the least snowfall days are June, July, August, September and October (0 days).
Average daylight in August /
Average sunshine in August
Portsmouth, RI
- Average daylight in August: 13h 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 August: 10h and 30min
The month with the most sunshine is August (Average sunshine: 10h and 30min).
The month with the least sunshine is February (Average sunshine: 4h and 48min).
Average sunshine days in August
Portsmouth, RI
- Average sunshine days in August: 16.9 days
The month with the most sunshine days is November (17.7 days).
The month with the least sunshine days is April (12.3 days).
Average UV index in August
Portsmouth, RI
- Average UV index in August: 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 and December (UV index 2).
Average cloud cover in August
Portsmouth, RI
- Average cloud cover in August: 29
The month with the most cloud cover is March (Cloud cover 48).
The month with the least cloud cover is August (Cloud cover 29).
Average visibility in August
Portsmouth, RI
- Average visibility in August: 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).





