What is the weather like in Mount Rainier National Park vs Olympic National Park in September?

In September, Mount Rainier National Park averages 10°C high / 0°C low with about 71 mm of rain; Olympic National Park averages 14°C high / 6°C low with about 148 mm.

Mount Rainier National Park vs Olympic National Park in September

Mount Rainier National Park is the better pick in September — 82 vs 78 on SeasonMap's comfort score. Mount Rainier National Park is cold, a little rain, clean air, while Olympic National Park is cool, rainy, clean air.

Mount Rainier National Park vs Olympic National Park — September climate, side by side

	🇺🇸 Mount Rainier National Park	🇺🇸 Olympic National Park
Comfort score	82/100 (A)	78/100 (B)
Feels-like high	7°C	12°C
Avg high / low	10° / 0°	14° / 6°
Rainfall	71 mm	148 mm
Rainy days	9	11
Humidity	72%	75%
Air quality (AQI)	33	31

Monthly climate normals (ERA5 reanalysis). Comfort scores are SeasonMap estimates.

Month by month

Mount Rainier National Park 🇺🇸 United Statescold, a little rain, clean air · best August82
Olympic National Park 🇺🇸 United Statescool, rainy, clean air · best August78

Mount Rainier National Park vs Olympic National Park in September — FAQ

Is September better in Mount Rainier National Park or Olympic National Park?: Mount Rainier National Park is the better pick in September — 82 vs 78 on SeasonMap's comfort score. Mount Rainier National Park is cold, a little rain, clean air, while Olympic National Park is cool, rainy, clean air.
What is the weather like in Mount Rainier National Park vs Olympic National Park in September?: In September, Mount Rainier National Park averages 10°C high / 0°C low with about 71 mm of rain; Olympic National Park averages 14°C high / 6°C low with about 148 mm.