Mount Rainier weather in September
Cold, with some rainy days. Average highs of -4°C and lows of -12°C, with around 10 rainy days expected throughout the month.
While September isn't our top-rated month for Mount Rainier, it has its own appeal — typically lower prices, fewer crowds, and a more local feel.
Average high
-4°C
Average low
-12°C
Rainy days
10 days
Best months to visit
Year-round
What to do in Mount Rainier in September
Whatever the weather, Mount Rainier rewards curious visitors. Here are some of the best ways to spend your time:
Explore
Dine
Culture
Nature
Shopping
Day trips
What to pack for September
Pack for cold weather — a proper winter coat, thermal layers, waterproof boots, and warm accessories. You'll want a good base layer for outdoor activities.
Browse other months
January
-17C
Cold, with frequent heavy rain.
February
-19C
Cold, with regular rainfall.
March
-17C
Cold, with regular rainfall.
April
-14C
Cold, with regular rainfall.
May
-9C
Cold, with regular rainfall.
June
-5C
Cold, with some rainy days.
July
1C
Cold, with occasional showers.
August
2C
Cold, with occasional showers.
September (you are here)
-4C
Cold, with some rainy days.
October
-9C
Cold, with regular rainfall.
November
-15C
Cold, with regular rainfall.
December
-18C
Cold, with frequent heavy rain.
Book your September trip to Mount Rainier
Find hotels, tours and experiences for the perfect escape.
