🇺🇸 Missoula vs 🇺🇸 San Francisco

Missoula in the Clark Fork River valley is famous for its air quality problems — winter inversions trap wood smoke and vehicle emissions in the mountain-ringed basin. The university town is surrounded by five valleys converging at this geographic pinch point, creating complex wind patterns. Fire smoke from regional wildfires is an increasing summer problem.

San Francisco's climate is shaped by its position on a peninsula surrounded by the Pacific Ocean and San Francisco Bay. The coastal fog (Karl the Fog) rolls in through the Golden Gate each summer afternoon, keeping temperatures mild year-round. The city has dramatically different microclimates — the Sunset District fog-bound while the Mission basks in sun on the same day.