September weather forecast
Sumner, ME

Share

Weather in September

The first month of the autumn, September, is still a pleasant month in Sumner, Maine, with an average temperature fluctuating between 47.3°F (8.5°C) and 68°F (20°C).

Temperature

With the commencement of September, Sumner records a moderate temperature decline, with the average high easing from August's moderately hot 75.6°F (24.2°C) to an agreeable 68°F (20°C). In Sumner, September is marked by an average low-temperature of 47.3°F (8.5°C).

Humidity

In Sumner, Maine, the average relative humidity in September is 79%.

Rainfall

In September, the rain falls for 11 days. Throughout September, 1.89" (48mm) of precipitation is accumulated. In Sumner, during the entire year, the rain falls for 146.3 days and collects up to 28.31" (719mm) of precipitation.

Snowfall

In Sumner, snow does not fall in June through September.

Daylight

In September, the average length of the day is 12h and 30min.
On the first day of September, sunrise is at 6:05 am and sunset at 7:17 pm. On the last day of the month, sunrise is at 6:39 am and sunset at 6:23 pm EDT.

Sunshine

In Sumner, the average sunshine in September is 8.2h.

UV index

In Sumner, Maine, the average daily maximum UV index in September is 3. A UV Index value of 3 to 5 symbolizes a medium health hazard from unprotected exposure to Sun's UV rays for the average person.
Note: The maximum UV index of 3 during September leads to these instructions:
Take necessary precautions - Defending against sun damage is advocated. Being exposed to the midday Sun can have harmful effects due to strong UV radiation; always take precautions. Counter UV radiation's ill effects with clothing designed for sun safety and UV-resistant eyewear.
Updated: Jul 28, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What is the temperature in September?

The high-temperature, in September, in Sumner, records 68°F (20°C), while the low-temperature is 47.3°F (8.5°C).

What is the average humidity in September?

The average relative humidity in September is 79%.

How much does it rain in September?

In Sumner, during September, the rain falls for 11 days and regularly aggregates up to 1.89" (48mm) of precipitation.

When it does not snow?

In Sumner, snow does not fall in June through September.

Does it snow in September?

In Sumner, in September, it doesn't snow. In October, it regularly snows.

How many hours of daylight does Sumner have in September?

The average day length in September is 12h and 30min.

What time are sunrise and sunset in September?

In September, on the first day of the month, sunrise is at 6:05 am and sunset at 7:17 pm. On the last day of the month, in Sumner, sunrise is at 6:39 am and sunset at 6:23 pm EDT.

How long on average sun shines in September?

In September, the average sunshine duration is 8.2h.

What is the UV index reading in September?

In September, the average daily maximum UV index is 3. A UV Index value of 3 to 5 symbolizes a moderate vulnerability from unprotected exposure to 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 September
Sumner, ME

Average temperature in September - Sumner, ME
  • Average high temperature in September: 68°F

The warmest month (with the highest average high temperature) is July (76.8°F).
The month with the lowest average high temperature is January (23.7°F).

  • Average low temperature in September: 47.3°F

The month with the highest average low temperature is July (55.4°F).
The coldest month (with the lowest average low temperature) is January (10°F).

Average pressure in September
Sumner, ME

Average pressure in September - Sumner, ME
  • Average pressure in September: 30.04"Hg

The month with the highest atmospheric pressure is November (30.05"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).

Average wind speed in September
Sumner, ME

Average wind speed in September - Sumner, ME
  • Average wind speed in September: 4.8mph

The windiest month (with the highest average wind speed) is March (6.8mph).
The calmest month (with the lowest average wind speed) is August (4.5mph).

Average humidity in September
Sumner, ME

Average humidity in September - Sumner, ME
  • Average humidity in September: 79%

The months with the highest relative humidity are January, February and March (86%).
The months with the lowest relative humidity are May and November (76%).

Average rainfall in September
Sumner, ME

Average rainfall in September - Sumner, ME
  • Average rainfall in September: 1.89"

The wettest month (with the highest rainfall) is October (3.31").
The driest month (with the least rainfall) is July (1.85").

Average rainfall days in September
Sumner, ME

Average rainfall days in September - Sumner, ME
  • Average rainfall days in September: 11 days

The month with the highest number of rainy days is June (15.5 days).
The month with the least rainy days is February (8.2 days).

Average snowfall in September
Sumner, ME

Average snowfall in September - Sumner, ME
  • Average snowfall in September: 0"

The month with the highest snowfall is February (12.28").
The months with the least snowfall are June, July, August and September (0").

Average snowfall days in September
Sumner, ME

Average snowfall days in September - Sumner, ME
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is February (15.3 days).
The months with the least snowfall days are June, July, August and September (0 days).

Average daylight in September /
Average sunshine in September
Sumner, ME

Average daylight in September / Average sunshine in September - Sumner, ME
  • Average daylight in September: 12h and 3min

The month with the longest days is June (Average daylight: 15h and 30min).
The month with the shortest days is December (Average daylight: 8h and 54min).

  • Average sunshine in September: 8h and 1min

The month with the most sunshine is August (Average sunshine: 9h and 42min).
The month with the least sunshine is February (Average sunshine: 4h and 0min).

Average sunshine days in September
Sumner, ME

Average sunshine days in September - Sumner, ME
  • Average sunshine days in September: 16.7 days

The month with the most sunshine days is September (16.7 days).
The months with the least sunshine days are February and April (11.3 days).

Average UV index in September
Sumner, ME

Average UV index in September - Sumner, ME
  • Average UV index in September: 3

The months with the highest UV index are June, July and August (UV index 5).
The months with the lowest UV index are February and December (UV index 1).

Average cloud cover in September
Sumner, ME

Average cloud cover in September - Sumner, ME
  • Average cloud cover in September: 40

The month with the most cloud cover is February (Cloud cover 57).
The month with the least cloud cover is September (Cloud cover 40).

Average visibility in September
Sumner, ME

Average visibility in September - Sumner, ME
  • Average visibility in September: 4mi

The months with the highest visibility are May, June, October, November and December (5mi).
The months with the lowest visibility are January, February, March, April, July, August and September (4mi).

Sumner, Maine, USA

Weather forecast for your location

1. Click Locate me button
2. Allow the app to use your location