Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
The start of September signals a gentle decrease in the average high-temperature, transitioning from a moderately hot 78.4°F (25.8°C) in August to an agreeable 71.2°F (21.8°C). In September, the average low-temperature records at a cool 52.2°F (11.2°C) during the nights.Humidity
In September, the average relative humidity is 79%.Rainfall
September is the month with the least rainfall. Rain falls for 11.9 days and accumulates 1.77" (45mm) of precipitation.Snowfall
In Petersham, snow does not fall in June through September.Daylight
The average length of the day in September in Petersham is 12h and 29min.On the first day of the month, sunrise is at 6:14 am and sunset at 7:22 pm. On the last day of September, sunrise is at 6:45 am and sunset at 6:31 pm EDT.
Sunshine
In September, the average sunshine is 8.4h.UV index
The average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV rays for ordinary individuals.Note: In September, the UV index of 4 transforms into the following advice:
Take precautions - Protection against sun damage is advised. The Sun's radiation is especially intense around midday; try to stay in shade during this period. A wide-brimmed hat provides unparalleled sun protection for sensitive areas like the eyes, ears, and neck.
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Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in September?
What is the average humidity in September?
What is the driest month?
How much does it rain in Petersham in September?
When it does not snow?
Does it snow in Petersham in September?
How many hours of daylight does Petersham have in September?
When is the sunrise / sunset in September?
How long on average sun shines in September?
What is the UV index intensity in September?
Average temperature in September
Petersham, MA
- Average high temperature in September: 71.2°F
The warmest month (with the highest average high temperature) is July (81°F).
The month with the lowest average high temperature is January (29.5°F).
- Average low temperature in September: 52.2°F
The month with the highest average low temperature is July (59.9°F).
The coldest month (with the lowest average low temperature) is January (17.1°F).
Average pressure in September
Petersham, MA
- Average pressure in September: 30.06"Hg
The month with the highest atmospheric pressure is November (30.08"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Petersham, MA
- Average wind speed in September: 5.6mph
The windiest months (with the highest average wind speed) are January, February and March (8.1mph).
The calmest month (with the lowest average wind speed) is August (5.2mph).
Average humidity in September
Petersham, MA
- Average humidity in September: 79%
The month with the highest relative humidity is February (83%).
The month with the lowest relative humidity is April (73%).
Average rainfall in September
Petersham, MA
- Average rainfall in September: 1.77"
The wettest month (with the highest rainfall) is October (2.8").
The driest month (with the least rainfall) is September (1.77").
Average rainfall days in September
Petersham, MA
- Average rainfall days in September: 11.9 days
The month with the highest number of rainy days is May (15.6 days).
The month with the least rainy days is January (7.4 days).
Average snowfall in September
Petersham, MA
- Average snowfall in September: 0"
The month with the highest snowfall is February (6.69").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Petersham, MA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (10.5 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Petersham, MA
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in September: 8h and 2min
The month with the most sunshine is August (Average sunshine: 10h and 12min).
The month with the least sunshine is February (Average sunshine: 4h and 30min).
Average sunshine days in September
Petersham, MA
- Average sunshine days in September: 15.2 days
The month with the most sunshine days is November (17.1 days).
The month with the least sunshine days is June (13 days).
Average UV index in September
Petersham, MA
- Average UV index in September: 4
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, March, October, November and December (UV index 2).
Average cloud cover in September
Petersham, MA
- Average cloud cover in September: 39
The months with the most cloud cover are February and March (Cloud cover 50).
The month with the least cloud cover is August (Cloud cover 35).
Average visibility in September
Petersham, MA
- Average visibility in September: 5mi
The month with the highest visibility is April (6mi).
The months with the lowest visibility are January, February, March, May, June, July, August, September, October, November and December (5mi).
Petersham, Massachusetts, USA
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