September weather forecastPort Townsend, WA
September
Weather in September
September in Port Townsend comes with cooler temperatures, a treat for those seeking a respite from the summer's warmth. Despite the mercury dropping to an average high of 63.1°F (17.3°C), the month remains inviting. The arrival of autumn paints the city in warm hues with less crowd, adding a quiet charm to it. September's transitional weather lends it an appealing mixture of summer's end and autumn's beginning.Temperature
Port Townsend marks the arrival of September with an average high-temperature of a still comfortable 63.1°F (17.3°C), hardly different from August's 67.8°F (19.9°C). Port Townsend's average low-temperature is measured at a cool 52.7°F (11.5°C) during September.Humidity
In Port Townsend, the average relative humidity in September is 79%.Rainfall
In Port Townsend, in September, during 12.5 rainfall days, 1.5" (38mm) of precipitation is typically accumulated. Throughout the year, there are 180.3 rainfall days, and 21.85" (555mm) of precipitation is accumulated.Snowfall
May through October are months without snowfall.Ocean temperature
August and September, with an average ocean temperature of 53.1°F (11.7°C), are months with the warmest seawater.Note: Swimming in 53.1°F (11.7°C) feels unbearing at 55.4°F (13°C) and can be life-risking below 50°F (10°C), causing breathing issues and cold shock, depending on a person's capacity.
Daylight
In September, the average length of the day is 12h and 33min.On the first day of the month, sunrise is at 6:30 am and sunset at 7:51 pm. On the last day of September, sunrise is at 7:10 am and sunset at 6:51 pm PDT.
Sunshine
The average sunshine in September is 9.5h.UV index
In Port Townsend, the average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a medium vulnerability from unsafe exposure to UV radiation for ordinary individuals.Note: In September, the maximum UV index of 4 translates into these guidelines:
Be vigilant - Preventing sunburn is recommended. Protect yourself from the midday Sun's peak UV radiation by minimizing exposure. Tightly woven clothing, when worn loosely, shields effectively against the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Port Townsend, WA
- Average high temperature in September: 63.1°F
The warmest month (with the highest average high temperature) is August (67.8°F).
The month with the lowest average high temperature is December (43°F).
- Average low temperature in September: 52.7°F
The month with the highest average low temperature is August (55.4°F).
The coldest month (with the lowest average low temperature) is February (37.4°F).
Average pressure in September
Port Townsend, WA
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is January (30.08"Hg).
The months with the lowest atmospheric pressure are March and September (30.01"Hg).
Average wind speed in September
Port Townsend, WA
- Average wind speed in September: 4.3mph
The windiest month (with the highest average wind speed) is November (7.4mph).
The calmest month (with the lowest average wind speed) is August (4mph).
Average humidity in September
Port Townsend, WA
- Average humidity in September: 79%
The month with the highest relative humidity is January (83%).
The month with the lowest relative humidity is July (75%).
Average rainfall in September
Port Townsend, WA
- Average rainfall in September: 1.5"
The wettest month (with the highest rainfall) is November (2.91").
The driest month (with the least rainfall) is July (0.43").
Average rainfall days in September
Port Townsend, WA
- Average rainfall days in September: 12.5 days
The month with the highest number of rainy days is March (20.7 days).
The month with the least rainy days is August (6.6 days).
Average snowfall in September
Port Townsend, WA
- Average snowfall in September: 0"
The month with the highest snowfall is February (2.87").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Port Townsend, WA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (2.8 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average sea temperature in September
Port Townsend, WA
- Average sea temperature in September: 52.9°F
The best month for swimming (with the highest average sea temperature) is August (53°F).
The coldest month (with the lowest average sea temperature) is February (45°F).
Average daylight in September /
Average sunshine in September
Port Townsend, WA
- Average daylight in September: 12h and 36min
The month with the longest days is June (Average daylight: 16h and 0min).
The month with the shortest days is December (Average daylight: 8h and 24min).
- Average sunshine in September: 9h and 30min
The month with the most sunshine is August (Average sunshine: 11h and 0min).
The month with the least sunshine is January (Average sunshine: 4h and 48min).
Average sunshine days in September
Port Townsend, WA
- Average sunshine days in September: 15.6 days
The month with the most sunshine days is August (22.3 days).
The month with the least sunshine days is March (8.2 days).
Average UV index in September
Port Townsend, WA
- Average UV index in September: 4
The month with the highest UV index is July (UV index 5).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Port Townsend, WA
- Average cloud cover in September: 30
The months with the most cloud cover are January, February and December (Cloud cover 50).
The month with the least cloud cover is August (Cloud cover 21).
Average visibility in September
Port Townsend, WA
- 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).
