September weather forecastHopkinton, RI
September
Weather in September
September is characteristic of a distinct tilt in Hopkinton's weather towards autumn. The warm days of summer begin to mildly recede, making way for slightly cooler conditions. Daylight hours start reducing significantly, hinting at the nearing end of the year. As the cloud cover begins to increase again, the decrease in wind speeds makes for calmer outdoor conditions. September's weather is marked by a significant reduction in daylight hours, down by over an hour from August to 12.5 hours.Temperature
Hopkinton in September undergoes a slight reduction in the average high-temperature, shifting from August's moderately hot 77.5°F (25.3°C) to an agreeable 71.2°F (21.8°C). In September, Hopkinton records an average nighttime temperature of 60.4°F (15.8°C).Humidity
In September, the average relative humidity is 78%.Rainfall
September is the month with the least rainfall in Hopkinton. Rain falls for 12.9 days and accumulates 1.73" (44mm) of precipitation.Snowfall
In Hopkinton, snow does not fall in May through October.Daylight
The average length of the day in September is 12h and 28min.On the first day of the month, sunrise is at 6:14 am and sunset at 7:19 pm. On the last day of September, sunrise is at 6:43 am and sunset at 6:30 pm EDT.
Sunshine
In Hopkinton, the average sunshine in September is 9h.UV index
In Hopkinton, the average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a moderate threat to health from unprotected exposure to Sun's UV rays for the ordinary person.Note: A daily maximum UV index of 4 in September translates into the following instructions:
Make use of precautions - It is urged to ward off sun damage. Being in direct Sun during midday can be harmful due to intense solar radiation; take precautions. 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 September
Hopkinton, RI
- Average high temperature in September: 71.2°F
The warmest month (with the highest average high temperature) is July (77.7°F).
The month with the lowest average high temperature is January (36.7°F).
- Average low temperature in September: 60.4°F
The month with the highest average low temperature is July (67.1°F).
The coldest month (with the lowest average low temperature) is January (27°F).
Average pressure in September
Hopkinton, RI
- Average pressure in September: 30.05"Hg
The month with the highest atmospheric pressure is November (30.08"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in September
Hopkinton, RI
- Average wind speed in September: 9.4mph
The windiest month (with the highest average wind speed) is January (12.5mph).
The calmest months (with the lowest average wind speed) are July and August (8.3mph).
Average humidity in September
Hopkinton, RI
- Average humidity in September: 78%
The months with the highest relative humidity are June and July (81%).
The months with the lowest relative humidity are March and November (74%).
Average rainfall in September
Hopkinton, RI
- Average rainfall in September: 1.73"
The wettest month (with the highest rainfall) is December (3.39").
The driest month (with the least rainfall) is September (1.73").
Average rainfall days in September
Hopkinton, RI
- Average rainfall days in September: 12.9 days
The month with the highest number of rainy days is July (17.3 days).
The month with the least rainy days is January (8.6 days).
Average snowfall in September
Hopkinton, RI
- Average snowfall in September: 0"
The month with the highest snowfall is March (1.85").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Hopkinton, RI
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (5.6 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Hopkinton, RI
- Average daylight in September: 12h and 30min
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 September: 9h and 0min
The month with the most sunshine is August (Average sunshine: 10h and 36min).
The months with the least sunshine are February and December (Average sunshine: 4h and 54min).
Average sunshine days in September
Hopkinton, RI
- Average sunshine days in September: 14.9 days
The month with the most sunshine days is November (18.3 days).
The month with the least sunshine days is July (11 days).
Average UV index in September
Hopkinton, RI
- Average UV index in September: 4
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 September
Hopkinton, RI
- Average cloud cover in September: 32
The months with the most cloud cover are March and December (Cloud cover 47).
The month with the least cloud cover is August (Cloud cover 28).
Average visibility in September
Hopkinton, RI
- Average visibility in September: 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).





