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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 sea temperature 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
The popular tourist spot of Bar Harbor in Maine, within the Mount Desert Island
Weather in September
September marks a noticeable shift in Bar Harbor's weather as it makes its transition from summer to fall. There is no snowfall during this month, indicating the lasting warmth of summer. Trees start to change their colors, providing an impressive palette of fall hues. Harvest festivals and hiking are popular, providing visitors with a beautiful backdrop. As daylight hours begin to shorten, the city gears up for the arrival of cooler temperatures.
Temperature
Bar Harbor's progression into September involves a minor drop in the average high-temperature, slightly receding from a moderately hot 73.4°F (23°C) in August to a comfortable 67.1°F (19.5°C). September nights cool down to an average low-temperature of 52.7°F (11.5°C).
Humidity
In September, the average relative humidity is 79%.
Rainfall
In Bar Harbor, in September, it is raining for 10.5 days, with typically 1.81" (46mm) of accumulated precipitation. In Bar Harbor, during the entire year, the rain falls for 142.1 days and collects up to 32.28" (820mm) of precipitation.
Snowfall
In Bar Harbor, snow does not fall in June through September.
Ocean temperature
In Bar Harbor, the average seawater temperature in September is 55.9°F (13.3°C).
Note: Dipping into 55.9°F (13.3°C) below 50°F (10°C) is possible with the right protection; absent that, anticipate cold shock and hampered breathing. Swimming momentarily at 55.4°F (13°C) can be jarring.
Daylight
In Bar Harbor, the average length of the day in September is 12h and 30min.
On the first day of the month, sunrise is at 5:56 am and sunset at 7:08 pm. On the last day of September, sunrise is at 6:30 am and sunset at 6:14 pm EDT.
Sunshine
In September, the average sunshine is 8.2h.
UV index
The average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a medium health hazard from exposure to the Sun's UV radiation for ordinary individuals.
Note: The UV index of 4 during September leads to these advisories:
Undertake precautions - Guarding against sun damage is counselled. The solar radiation around mid-day is intense; avoid the Sun and stay safe. Always opt for UVA and UVB-resistant sunglasses on radiant days.
Updated: Aug 27, 2024
Published by: Weather Atlas | About Us
Data Sources |
Frequently asked questions
What is the usual temperature for Bar Harbor in September?
In September, in Bar Harbor, the average high-temperature is 67.1°F (19.5°C), and the average low-temperature is 52.7°F (11.5°C).
What is the average humidity in September?
In Bar Harbor, the average relative humidity in September is 79%.
How much does it rain in September?
In Bar Harbor, during September, the rain falls for 10.5 days and regularly aggregates up to 1.81" (46mm) of precipitation.
When it does not snow in Bar Harbor?
In Bar Harbor, snow does not fall in June through September.
Does it snow in September?
In Bar Harbor, in September, it doesn't snow. In October, it regularly snows.
What is the ocean temperature in September?
In September, the average ocean temperature in Bar Harbor is 55.9°F (13.3°C). Swimming in 55.9°F (13.3°C) is considered life-threatening. Even a few minutes in 55.4°F (13°C) water is uncomfortable, and swimming below 50°F (10°C) may cause total loss of breathing control and cold shock, depending on a person's physique.
How many hours of daylight does Bar Harbor have in September?
In September, the average day length is 12h and 30min.
When are sunrise and sunset in September?
On the first day of September, sunrise is at 5:56 am and sunset at 7:08 pm. On the last day of the month, sunrise is at 6:30 am and sunset at 6:14 pm EDT.
How long on average sun shines in September?
The average sunshine duration in September is 8.2h.
What is the UV index reading in September?
The average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a medium health risk from exposure to Sun's UV rays.
Today
Tomorrow
Long-term
YearJFMAMJJASeptemberOND
September
Oct
Average high temperature
73.4°F 23°C
67.1°F 19.5°C
55.9°F 13.3°C
Average low temperature
57.7°F 14.3°C
52.7°F 11.5°C
45°F 7.2°C
Average pressure
29.96" 761mmHg
30.04" 763mmHg
29.99" 762mmHg
Average wind speed
6.3mph 10.1km/h
7.1mph 11.4km/h
8.9mph 14.3km/h
Average max. wind speed
7mph 11.3km/h
7.4mph 11.9km/h
9.7mph 15.6km/h
Average wind speed gusts
10.1mph 16.3km/h
11.4mph 18.3km/h
14.4mph 23.2km/h
Average humidity
80%
79%
78%
Average rainfall
1.73" 44mm
1.81" 46mm
3.35" 85mm
Average rainfall days
10.4
10.5
14
Average snowfall
0" 0mm
0" 0mm
0.04" 1mm
Average snowfall days
0.3
Average sea temperature
56.8°F 13.8°C
55.9°F 13.3°C
53.3°F 11.8°C
Average daylight
14h 0min
12h 3min
11h 0min
Average sunshine
10h 1min
8h 1min
6h 2min
Average sunshine days
18.7
17.5
14.5
Average UV index
5
4
3
Average cloud cover
35%
35%
44%
Average visibility
5mi 8km
6mi 9.7km
6mi 9.7km
Average temperature in September
Bar Harbor, ME
- Average high temperature in September: 67.1°F
The warmest month (with the highest average high temperature) is August (73.4°F).
The month with the lowest average high temperature is January (29.7°F).
- Average low temperature in September: 52.7°F
The month with the highest average low temperature is July (58.1°F).
The coldest month (with the lowest average low temperature) is January (18.5°F).
Average pressure in September
Bar Harbor, ME
- Average pressure in September: 30.04"Hg
The month with the highest atmospheric pressure is September (30.04"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in September
Bar Harbor, ME
- Average wind speed in September: 7.1mph
The windiest month (with the highest average wind speed) is January (10.4mph).
The calmest months (with the lowest average wind speed) are July and August (6.3mph).
Average humidity in September
Bar Harbor, ME
- Average humidity in September: 79%
The month with the highest relative humidity is February (83%).
The month with the lowest relative humidity is November (76%).
Average rainfall in September
Bar Harbor, ME
- Average rainfall in September: 1.81"
The wettest month (with the highest rainfall) is December (3.94").
The driest month (with the least rainfall) is July (1.57").
Average rainfall days in September
Bar Harbor, ME
- Average rainfall days in September: 10.5 days
The month with the highest number of rainy days is April (15.5 days).
The month with the least rainy days is February (7.5 days).
Average snowfall in September
Bar Harbor, ME
- Average snowfall in September: 0"
The month with the highest snowfall is February (5.75").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Bar Harbor, ME
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (11.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average sea temperature in September
Bar Harbor, ME
- Average sea temperature in September: 55.9°F
The best month for swimming (with the highest average sea temperature) is August (56.8°F).
The coldest month (with the lowest average sea temperature) is March (38.6°F).
Average daylight in September /
Average sunshine in September
Bar Harbor, 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: 10h and 6min).
The month with the least sunshine is February (Average sunshine: 4h and 6min).
Average sunshine days in September
Bar Harbor, ME
- Average sunshine days in September: 17.5 days
The month with the most sunshine days is August (18.7 days).
The month with the least sunshine days is April (11.2 days).
Average UV index in September
Bar Harbor, ME
- Average UV index in September: 4
The months with the highest UV index are June, July and August (UV index 5).
The months with the lowest UV index are January, February, March, November and December (UV index 2).
Average cloud cover in September
Bar Harbor, ME
- Average cloud cover in September: 35
The month with the most cloud cover is February (Cloud cover 56).
The months with the least cloud cover are August and September (Cloud cover 35).
Average visibility in September
Bar Harbor, ME
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are July and August (5mi).
