September weather forecastHaines, AK
September
Weather in September
As August's warmth begins to ebb, September marks the beginning of autumn's entrance. Weather patterns turn unpredictable with cooler temperatures and a blend of sun and showers. The first hint of Alaska's stunning fall foliage starts to peek through adding a brilliant spectrum of colors to the landscape. The month acts as a bridge between the dissipating summer and incoming chill of late autumn. Enjoy all that the Alaskan fall offers as the landscapes prepare for a stunning color transformation.Temperature
The start of September comes with a small reduction in the average high-temperature, subtly receding from a cool 55°F (12.8°C) in August to a frosty 47.3°F (8.5°C). A consistent nighttime average temperature of 38.7°F (3.7°C) is maintained during September.Humidity
The average relative humidity in September is 84%.Rainfall
In Haines, in September, it is raining for 19.5 days, with typically 4.65" (118mm) of accumulated precipitation. In Haines, during the entire year, the rain falls for 200.4 days and collects up to 48.03" (1220mm) of precipitation.Snowfall
In Haines, snow does not fall in June through September.Ocean temperature
In September, the average ocean temperature is 50.5°F (10.3°C).Note: In 50.5°F (10.3°C), cold shock and rapid breathing can occur when swimming at temperatures below 50°F (10°C).
Daylight
The average length of the day in September is 12h and 48min.On the first day of the month, sunrise is at 6:01 am and sunset at 8:01 pm. On the last day of September, sunrise is at 7:06 am and sunset at 6:36 pm AKDT.
Sunshine
In Haines, the average sunshine in September is 6.4h.UV index
The average daily maximum UV index in September is 2. A UV Index of 2, and less, symbolizes a low threat to health from unprotected exposure to Sun's UV rays for ordinary individuals.Note: The maximum UV index, 2 during September, leads to the following recommendations:
Children must always have sun protection, unlike most people, who can tolerate up to an hour in the sun without any burns. Solar radiation peaks around mid-day, so it's wise to limit exposure to the Sun at this time. Combat UV radiation's detrimental effects with sun-safe clothing and UV-blocking eyewear.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Haines, AK
- Average high temperature in September: 47.3°F
The warmest month (with the highest average high temperature) is July (56.5°F).
The month with the lowest average high temperature is January (21.6°F).
- Average low temperature in September: 38.7°F
The month with the highest average low temperature is August (44.1°F).
The coldest month (with the lowest average low temperature) is February (12.4°F).
Average pressure in September
Haines, AK
- Average pressure in September: 29.87"Hg
The month with the highest atmospheric pressure is July (30.01"Hg).
The month with the lowest atmospheric pressure is November (29.81"Hg).
Average wind speed in September
Haines, AK
- Average wind speed in September: 5.6mph
The windiest month (with the highest average wind speed) is January (6.7mph).
The calmest month (with the lowest average wind speed) is May (4.7mph).
Average humidity in September
Haines, AK
- Average humidity in September: 84%
The month with the highest relative humidity is January (92%).
The month with the lowest relative humidity is May (78%).
Average rainfall in September
Haines, AK
- Average rainfall in September: 4.65"
The wettest month (with the highest rainfall) is November (5.87").
The driest month (with the least rainfall) is June (2.2").
Average rainfall days in September
Haines, AK
- Average rainfall days in September: 19.5 days
The month with the highest number of rainy days is October (20.2 days).
The month with the least rainy days is February (9.3 days).
Average snowfall in September
Haines, AK
- Average snowfall in September: 0"
The month with the highest snowfall is December (21.06").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Haines, AK
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is December (17.1 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average sea temperature in September
Haines, AK
- Average sea temperature in September: 50.5°F
The best month for swimming (with the highest average sea temperature) is August (53.1°F).
The coldest month (with the lowest average sea temperature) is March (39.6°F).
Average daylight in September /
Average sunshine in September
Haines, AK
- Average daylight in September: 12h and 48min
The month with the longest days is June (Average daylight: 18h and 30min).
The month with the shortest days is December (Average daylight: 6h and 18min).
- Average sunshine in September: 6h and 24min
The month with the most sunshine is June (Average sunshine: 10h and 12min).
The months with the least sunshine are January and December (Average sunshine: 3h and 42min).
Average sunshine days in September
Haines, AK
- Average sunshine days in September: 8.2 days
The month with the most sunshine days is February (10.4 days).
The month with the least sunshine days is June (6.3 days).
Average UV index in September
Haines, AK
- Average UV index in September: 2
The month with the highest UV index is July (UV index 4).
The months with the lowest UV index are February, November and December (UV index 1).
Average cloud cover in September
Haines, AK
- Average cloud cover in September: 59
The month with the most cloud cover is December (Cloud cover 63).
The month with the least cloud cover is May (Cloud cover 47).
Average visibility in September
Haines, AK
- Average visibility in September: 5mi
The months with the highest visibility are May, June, July, August, September and October (5mi).
The months with the lowest visibility are January, February, March, April, November and December (4mi).
