Eugene has a **warm-summer Mediterranean climate (Köppen Csb)**, with dry summers and wetter winters. Seasonal patterns are shaped by Pacific weather systems, valley geography, and occasional continental air intrusions.
| Season | Typical Conditions | |---|---| | Winter | Cool, wet, often cloudy; daytime highs commonly in the upper 40s to low 50s °F (8-12 °C) | | Spring | Mild and gradually drying; frequent rain early, greener landscapes, warming by late season | | Summer | Warm, dry, and sunnier; highs often in the upper 70s to mid-80s °F (26-30 °C), with periodic hotter spells | | Autumn | Mild, then increasingly wet; early fall is often pleasant and dry |
- **Rainfall:** Most precipitation falls from late autumn through spring. Annual precipitation is substantial, though generally lower than on the Oregon coast. - **Snowfall:** Snow is usually light and infrequent in the city, though winter ice or occasional snow events can disrupt travel. - **Humidity:** Relative humidity is often high in cooler months; summer afternoons are usually more comfortable than in humid continental climates. - **Best time to visit:** Late spring through early fall is often the most convenient period for outdoor recreation, campus visits, festivals, and athletics events. - **Natural hazards:** Eugene can experience river flooding, winter storms, wildfire smoke during some summer or fall seasons, and earthquake risk typical of the Pacific Northwest. Extreme heat events have also become a growing concern.
Average temperatures vary by elevation and season, but Eugene is generally milder than inland Oregon and less rainy than the coast, making it one of the state's more moderate urban climates.
