Seattle weather
Our guide to the weather in Seattle during September
We've looked at the most up-to-date weather data for Seattle, covering the last 12 years up to 2026, plus we've asked our team of travel bloggers for their first-hand experiences in order to answer the most frequently asked questions about Seattle weather in September.
How warm is it in Seattle during September?
The temperature reaches around 23℃ during the daytime in September, falling away to 12℃ at night. The UV index will be moderate at this time of year, so not something to worry about for the average person. However, if you're going to be outside for long periods it's worth wearing a broad spectrum SPF 30+ sunscreen and UV-blocking sunglasses. Remember that bright surfaces, such as water and sand increase UV exposure.
Does it rain in Seattle during September?
On average, there will be 3 rainy days during the month, amounting to 31.7mm in total. That's much drier than we see in England during August, and therefore not something to be concerned about. There's a small chance that you'll catch a thunderstorm during your trip.
Is it windy in Seattle during September?
You're unlikely to experience any strong winds. Expect a light breeze that picks up slightly at times in September.
Seattle Blog posts
From the UK's most popular travel bloggers
Weekend in Seattle itinerary: Fun 3 days in Seattle!
26th January 2022 by PommieTravels
My initial impressions of Seattle were so-so. First of all, it was November and super rainy and chilly. When it rains in Seattle, it really rains, which is why the city often gets a bad rap. Coming from the airport Seattle also looks very industrial, with lots of shipping containers and factories. Aircraft manufacturer Boeing has a factory here and big name companies such as Amazon, Costco Wholesale, Microsoft and Starbucks are all headquartered in and around Seattle. Seattle is a rapidly...
10 cheap & affordable things to do in Seattle
5th February 2020 by Twins that Travel
There’s no escaping it: as beautiful, nature-filled and outdoorsy as Seattle might be, this is a city that comes with a price tag. A rather hefty one. With average budgets (for a three day trip) coming in at $500 per person, the high cost of the city’s ticketed attractions, its restaurants and its cool rooftop bars quickly add up. This is certainly something we experienced when we visited the city during our own road trip from Seattle to San Francisco. In fact, out of all the spots we...
The ultimate Pacific Northwest road trip itinerary: Driving Seattle to San Francisco
28th October 2019 by Twins that Travel
Traditionally, road trip itineraries for the Pacific North West are limited to the states of Washington and Oregon; with the option to drive north if you’re feeling particularly adventurous. However, what if you were to go further afield - turning your back on BC’s snow capped mountains in favour of North California’s warmer climes? What if you were to drive from Seattle to San Francisco - a Pacific Northwest road trip with a difference?...
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