Average September Temperatures for Oregon

Average temperatures for September at cities, towns, parks and lakes throughout Oregon are listed below in degrees Fahrenheit and Celsius.

You can jump to a separate table for each region of the state: Oregon Coast, Willamette Valley, Cascade Mountains, Central Oregon and Eastern Oregon.

The tables give the normals for maximum and minimum temperatures based on weather data collected from 1991 to 2020 by the US National Centers for Environmental Information.

Oregon Coast

Average September temperatures
High °F	Low °F	Place	High °C	Low °C
68	51	Astoria	20	10
67	52	Brookings	19	11
69	52	Gold Beach	20	11
66	50	Honeyman State Park	19	10
64	49	Newport	18	9
67	51	North Bend	19	11
67	51	Port Orford	20	11
67	50	Seaside	19	10
68	47	Tillamook	20	8

Willamette Valley

Average daily temperatures in September
High °F	Low °F	Place	High °C	Low °C
78	48	Corvallis	25	9
78	48	Eugene	26	9
79	51	Lebanon	26	10
76	53	Portland	24	12
78	51	Salem	25	10

Cascade Mountains

September temperatures: daily averages
High °F	Low °F	Place	High °C	Low °C
63	37	Crater Lake Park	17	3
74	53	Detroit Lake Dam	23	12
64	45	Government Camp	18	7
84	48	Grants Pass	29	9
72	40	Howard Prairie Lake Dam	22	4
78	39	Klamath Falls	25	4
76	40	Lakeview	25	5
76	45	McKenzie Bridge	25	7
84	51	Medford	29	11
83	50	Roseburg	28	10
73	48	Three Lynx	23	9
76	46	Toketee Falls	24	8
75	38	Wickiup Reservoir Dam	24	4

Central Oregon

Average September temperatures
High °F	Low °F	Place	High °C	Low °C
76	41	Bend	24	5
76	47	Hood River	24	9
77	38	Madras	25	3
81	49	The Dalles	27	10

Eastern Oregon

Average September temperatures
High °F	Low °F	Place	High °C	Low °C
74	39	Hart Mountain Antelope Refuge	23	4
77	48	Heppner	25	9
77	45	La Grande	25	7
83	45	Lake Owyhee Dam	28	7
75	40	Malheur National Wildlife Refuge	24	4
81	47	Ontario	27	9
80	47	Pendleton	27	8
73	27	Seneca	23	-3
81	40	Summer Lake	27	4

Average Temperatures for Oregon in September

Oregon Coast

Willamette Valley

Cascade Mountains

Central Oregon

Eastern Oregon

Reference

More Oregon Weather Information