Pendleton weather in September

In September, Pendleton sees average daytime highs of 76°F and overnight lows near 51°F, with 0.5 in of rain across 2.9 wet days and about 12.3 hours of daylight. It is the 4th-warmest and 10th-wettest month of the year here.

Highs ease over the month, from about 81°F in the first days to 72°F by the end. The sky is clear or mostly clear about 60% of the time in September, and the air most often feels dry.

Daylight stretches from about 13 h 06 min at the start of September to 11 h 30 min by month's end. Set against the rest of the year, September is Pendleton's 3rd-clearest and 12th-windiest month. For the whole year in context, see Pendleton's year-round climate.

Daytime high: 76°; 4th warmest
Overnight low: 51°; 9th coldest
Rainfall: 0.5 in; 2.9 wet days
Daylight: 12 h 18 min; 5:40 AM – 5:59 PM
Cloud cover: 34%; 3rd clearest
Wind: 5 mph; 12th windiest
Solar energy: 5.06 kWh/m²
Travel score: 8.3; out of 10

Pendleton is city in and seat of Umatilla County, Oregon, United States.

Density: 620/km²; people per km²
Founded: 1851

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

← August Pendleton year-round climate October →Best places to visit in September

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 81°F in the first days to 72°F by the end.

A typical September day in Pendleton reaches about 76°F in the afternoon and slips back to 51°F overnight — a 26°F spread between the day's warmth and the night's chill. On most days the high lands between 66°F and 87°F. Set against its neighbours, September runs about 10°F cooler than August and about 14°F warmer than October.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Avg high (°F)	82	81	81	81	80	80	80	79	79	79	78	78	77	77	77	76	76	76	75	75	74	74	74	73	73	73	72	72	71	71
Avg low (°F)	55	55	54	54	54	54	53	53	53	53	52	52	52	51	51	51	51	50	50	50	49	49	49	49	48	48	48	47	47	47

	Avg high (°F)	Avg low (°F)
1	82	55
2	81	55
3	81	54
4	81	54
5	80	54
6	80	54
7	80	53
8	79	53
9	79	53
10	79	53
11	78	52
12	78	52
13	77	52
14	77	51
15	77	51
16	76	51
17	76	51
18	76	50
19	75	50
20	75	50
21	74	49
22	74	49
23	74	49
24	73	49
25	73	48
26	73	48
27	72	48
28	72	47
29	71	47
30	71	47

How September really feels in Pendleton

Once humidity and wind are folded in, September averages 0 days that feel above 90°F and 0 that feel at or below 32°F — the comfort signal a plain temperature reading hides.

Days feeling ≥ 90°F

heat index over the day's high

Days feeling ≤ 32°F

wind chill below the day's low

September sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Pendleton weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 10th-wettest month here — the current month is highlighted below.

Month	High / Low (°F)	Rainfall (inches)	Wet days	Snow days	Daylight (hours)	Travel score
Jan	42° / 30°	2.3	12.6	4.3	8.9	0.2
Feb	46° / 31°	1.8	10.4	3.2	10.1	1.3
Mar	54° / 35°	2.1	10.9	1.4	11.6	3.1
Apr	61° / 40°	1.6	9.4	0.5	13.3	5.1
May	70° / 47°	1.5	7.3	0	14.7	6.9
Jun	77° / 53°	0.9	4.6	0	15.4	7.8
Jul	87° / 59°	0.2	1.1	0	15.1	6.1
Aug	86° / 58°	0.3	1.4	0	13.9	6.5
Sep	76° / 51°	0.5	2.9	0	12.3	8.3
Oct	63° / 42°	1.5	7.6	0.2	10.7	5.8
Nov	49° / 34°	2.3	12	2.1	9.3	1.9
Dec	41° / 29°	2.5	13	5	8.6	0.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 60% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 16% of September, with mostly cloudy or overcast conditions the remaining 25%. Skies tend to cloud over as the month goes on.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Clearer (%)	85	84	84	83	82	81	81	79	79	78	78	76	76	75	74	74	73	73	72	72	71	71	71	71	71	71	71	70	70	69
Cloudier (%)	15	16	16	17	18	19	19	21	21	22	22	24	24	25	26	26	27	27	28	28	29	29	29	29	29	29	29	30	30	31

	Clearer (%)	Cloudier (%)
1	85	15
2	84	16
3	84	16
4	83	17
5	82	18
6	81	19
7	81	19
8	79	21
9	79	21
10	78	22
11	78	22
12	76	24
13	76	24
14	75	25
15	74	26
16	74	26
17	73	27
18	73	27
19	72	28
20	72	28
21	71	29
22	71	29
23	71	29
24	71	29
25	71	29
26	71	29
27	71	29
28	70	30
29	70	30
30	69	31

Chance of precipitation in September

Any precipitation

Pendleton gets around 0.5 in of rain over 2.9 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 10% and peaks near 15% on the wettest days. The odds climb toward the end of the month.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Rain chance (%)	6	6	6	6	6	7	7	8	8	9	9	9	10	10	10	10	10	10	11	11	11	12	12	12	12	13	13	14	14	15

	Rain chance (%)
1	6
2	6
3	6
4	6
5	6
6	7
7	7
8	8
9	8
10	9
11	9
12	9
13	10
14	10
15	10
16	10
17	10
18	10
19	11
20	11
21	11
22	12
23	12
24	12
25	12
26	13
27	13
28	14
29	14
30	15

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

Most of September feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, September lands in the dry band about 99% of days. It rarely turns muggy — the humid and sticky bands barely register.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Dry (%)	99	99	99	99	99	99	99	99	99	99	99	99	99	99	99	99	99	99	99	99	99	99	99	99	99	99	99	100	100	100
Comfortable (%)	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	1	0	0	0

	Dry (%)	Comfortable (%)
1	99	1
2	99	1
3	99	1
4	99	1
5	99	1
6	99	1
7	99	1
8	99	1
9	99	1
10	99	1
11	99	1
12	99	1
13	99	1
14	99	1
15	99	1
16	99	1
17	99	1
18	99	1
19	99	1
20	99	1
21	99	1
22	99	1
23	99	1
24	99	1
25	99	1
26	99	1
27	99	1
28	100	0
29	100	0
30	100	0

Wind in September

Winds average 5 mph in September, the calmest month.

Across September, daily wind ranges from about 5 mph on the calmest days to 6 mph at its breeziest. It stays fairly steady from day to day.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Wind speed (mph)	6	6	6	6	6	6	6	6	6	6	6	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5	5
Feels	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm

	Wind speed (mph)	Feels
1	6	calm
2	6	calm
3	6	calm
4	6	calm
5	6	calm
6	6	calm
7	6	calm
8	6	calm
9	6	calm
10	6	calm
11	6	calm
12	5	calm
13	5	calm
14	5	calm
15	5	calm
16	5	calm
17	5	calm
18	5	calm
19	5	calm
20	5	calm
21	5	calm
22	5	calm
23	5	calm
24	5	calm
25	5	calm
26	5	calm
27	5	calm
28	5	calm
29	5	calm
30	5	calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 h 06 min at the start of September to 11 h 30 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 96 minutes over September. Sunrise moves from 5:21 AM to 5:58 AM, and sunset from 6:29 PM to 5:31 PM.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Daylight (h)	13.1	13.1	13.0	13.0	12.9	12.9	12.8	12.8	12.7	12.6	12.6	12.5	12.5	12.4	12.4	12.3	12.3	12.2	12.2	12.1	12.0	12.0	11.9	11.9	11.8	11.8	11.7	11.7	11.6	11.5
Sunrise (AM)	5:21	5:22	5:23	5:25	5:26	5:27	5:29	5:30	5:31	5:32	5:34	5:35	5:36	5:37	5:39	5:40	5:41	5:43	5:44	5:45	5:46	5:48	5:49	5:50	5:52	5:53	5:54	5:55	5:57	5:58
Sunset (PM)	6:29	6:27	6:25	6:23	6:21	6:19	6:17	6:15	6:13	6:11	6:09	6:07	6:05	6:03	6:01	5:59	5:57	5:55	5:53	5:51	5:49	5:47	5:45	5:43	5:41	5:39	5:37	5:35	5:33	5:31

	Daylight (h)	Sunrise (AM)	Sunset (PM)
1	13.1	5:21	6:29
2	13.1	5:22	6:27
3	13.0	5:23	6:25
4	13.0	5:25	6:23
5	12.9	5:26	6:21
6	12.9	5:27	6:19
7	12.8	5:29	6:17
8	12.8	5:30	6:15
9	12.7	5:31	6:13
10	12.6	5:32	6:11
11	12.6	5:34	6:09
12	12.5	5:35	6:07
13	12.5	5:36	6:05
14	12.4	5:37	6:03
15	12.4	5:39	6:01
16	12.3	5:40	5:59
17	12.3	5:41	5:57
18	12.2	5:43	5:55
19	12.2	5:44	5:53
20	12.1	5:45	5:51
21	12.0	5:46	5:49
22	12.0	5:48	5:47
23	11.9	5:49	5:45
24	11.9	5:50	5:43
25	11.8	5:52	5:41
26	11.8	5:53	5:39
27	11.7	5:54	5:37
28	11.7	5:55	5:35
29	11.6	5:57	5:33
30	11.5	5:58	5:31

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 5.06 kWh/m².

For context, solar energy here swings from a low near 1.29 kWh/m² to a high of 7.84 kWh/m² in July across the year — September's 5.06 kWh/m² falls in the middle.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Solar energy (kWh/m²)	6.0	5.9	5.8	5.8	5.7	5.7	5.6	5.5	5.5	5.4	5.3	5.3	5.2	5.2	5.1	5.0	5.0	4.9	4.8	4.8	4.7	4.7	4.6	4.5	4.5	4.4	4.3	4.3	4.2	4.1
Level	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright

	Solar energy (kWh/m²)	Level
1	6.0	Bright
2	5.9	Bright
3	5.8	Bright
4	5.8	Bright
5	5.7	Bright
6	5.7	Bright
7	5.6	Bright
8	5.5	Bright
9	5.5	Bright
10	5.4	Bright
11	5.3	Bright
12	5.3	Bright
13	5.2	Bright
14	5.2	Bright
15	5.1	Bright
16	5.0	Bright
17	5.0	Bright
18	4.9	Bright
19	4.8	Bright
20	4.8	Bright
21	4.7	Bright
22	4.7	Bright
23	4.6	Bright
24	4.5	Bright
25	4.5	Bright
26	4.4	Bright
27	4.3	Bright
28	4.3	Bright
29	4.2	Bright
30	4.1	Bright

Planning a trip in September

Is September a good time to visit Pendleton?

Our two travel scores rate September for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

8.3

Sightseeing

1st-best month of the year

7.2

Beach & pool

3rd-best month of the year

September is one of the better times to visit Pendleton for general sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Pendleton in September

From September's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In September, Pendleton sees daytime highs around 76°F and nights near 51°F. Worth packing: light clothes and sun protection.

light clothessun protection

UV index in Pendleton in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 5 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Pendleton peaks around July 15 at about 8 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 14 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
UV index (midday)	2	2	4	5	8	7	9	6	5	4	1	1
Level	Low	Low	Moderate	High	Very high	Very high	Very high	High	Moderate	Moderate	Low	Low

	UV index (midday)	Level
Jan	2	Low
Feb	2	Low
Mar	4	Moderate
Apr	5	High
May	8	Very high
Jun	7	Very high
Jul	9	Very high
Aug	6	High
Sep	5	Moderate
Oct	4	Moderate
Nov	1	Low
Dec	1	Low

Air quality in Pendleton in September

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where September falls, not just the annual average.

Air quality in Pendleton is worst in August — around 29 µg/m³ PM2.5 (moderate), about 4.4× the cleanest month (December, 7 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
PM2.5 (µg/m³)	7	8	11	11	9	9	16	29	20	12	12	7
Level	Good	Good	Good	Good	Good	Good	Moderate	Moderate	Moderate	Moderate	Good	Good

	PM2.5 (µg/m³)	Level
Jan	7	Good
Feb	8	Good
Mar	11	Good
Apr	11	Good
May	9	Good
Jun	9	Good
Jul	16	Moderate
Aug	29	Moderate
Sep	20	Moderate
Oct	12	Moderate
Nov	12	Good
Dec	7	Good

Location & terrain

Where is Pendleton?

Pendleton sits at 45.7°N, 118.8°W, 1,066 ft above sea level, in United States. The nearest listed city is Hermiston, 27 mi away.

Topography around Pendleton

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Pendleton.

Within 2 miles, the terrain around Pendleton has only modest variations in elevation — a maximum elevation change of 486 ft around an average of 1,250 ft above sea level; within 10 miles, large variations in elevation — a maximum elevation change of 2,136 ft; within 50 miles, very significant variations in elevation — a maximum elevation change of 6,581 ft.

The land around Pendleton is covered by grassland (41%), cropland (27%) and artificial surfaces (22%) within 2 miles, cropland (55%) and grassland (41%) within 10 miles, and grassland (43%), cropland (28%) and trees (27%) within 50 miles.

2 miles

486 ft

grassland 41%

10 miles

2,136 ft

cropland 55%

50 miles

6,581 ft

grassland 43%

treesgrasslandcroplandartificial surfacesbare terrainwater

← August Pendleton year-round climate October →Best places to visit in September

September weather nearby: Hermiston 27 mi · Walla Walla 35 mi · Kennewick 41 mi · Pasco 42 mi · Tri-Cities 44 mi · Richland 48 mi · Sunnyside 74 mi · Lewiston 99 mi

United States travel facts

Power plugs: Type A / B; 120 V · 60 Hz
Prices: ≈ 100% of US; price level, 2025
GDP per capita: $90,027; 2025
Happiness: 6.8 / 10; World Happiness, 2025
Safe drinking water: 98%; of population, 2024
Homicide rate: 5.8; per 100k, 2023
Road deaths: 12.7; per 100k/yr, 2019
Income group: High; World Bank
Religion

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Pendleton (45.6721°, -118.7886°, elevation 1,066 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).

	Avg high (°F)	Avg low (°F)
1	82	55
2	81	55
3	81	54
4	81	54
5	80	54
6	80	54
7	80	53
8	79	53
9	79	53
10	79	53
11	78	52
12	78	52
13	77	52
14	77	51
15	77	51
16	76	51
17	76	51
18	76	50
19	75	50
20	75	50
21	74	49
22	74	49
23	74	49
24	73	49
25	73	48
26	73	48
27	72	48
28	72	47
29	71	47
30	71	47

	Clearer (%)	Cloudier (%)
1	85	15
2	84	16
3	84	16
4	83	17
5	82	18
6	81	19
7	81	19
8	79	21
9	79	21
10	78	22
11	78	22
12	76	24
13	76	24
14	75	25
15	74	26
16	74	26
17	73	27
18	73	27
19	72	28
20	72	28
21	71	29
22	71	29
23	71	29
24	71	29
25	71	29
26	71	29
27	71	29
28	70	30
29	70	30
30	69	31

	Rain chance (%)
1	6
2	6
3	6
4	6
5	6
6	7
7	7
8	8
9	8
10	9
11	9
12	9
13	10
14	10
15	10
16	10
17	10
18	10
19	11
20	11
21	11
22	12
23	12
24	12
25	12
26	13
27	13
28	14
29	14
30	15

	Dry (%)	Comfortable (%)
1	99	1
2	99	1
3	99	1
4	99	1
5	99	1
6	99	1
7	99	1
8	99	1
9	99	1
10	99	1
11	99	1
12	99	1
13	99	1
14	99	1
15	99	1
16	99	1
17	99	1
18	99	1
19	99	1
20	99	1
21	99	1
22	99	1
23	99	1
24	99	1
25	99	1
26	99	1
27	99	1
28	100	0
29	100	0
30	100	0

	Avg high (°F)	Avg low (°F)
1	82	55
2	81	55
3	81	54
4	81	54
5	80	54
6	80	54
7	80	53
8	79	53
9	79	53
10	79	53
11	78	52
12	78	52
13	77	52
14	77	51
15	77	51
16	76	51
17	76	51
18	76	50
19	75	50
20	75	50
21	74	49
22	74	49
23	74	49
24	73	49
25	73	48
26	73	48
27	72	48
28	72	47
29	71	47
30	71	47

	Clearer (%)	Cloudier (%)
1	85	15
2	84	16
3	84	16
4	83	17
5	82	18
6	81	19
7	81	19
8	79	21
9	79	21
10	78	22
11	78	22
12	76	24
13	76	24
14	75	25
15	74	26
16	74	26
17	73	27
18	73	27
19	72	28
20	72	28
21	71	29
22	71	29
23	71	29
24	71	29
25	71	29
26	71	29
27	71	29
28	70	30
29	70	30
30	69	31

	Rain chance (%)
1	6
2	6
3	6
4	6
5	6
6	7
7	7
8	8
9	8
10	9
11	9
12	9
13	10
14	10
15	10
16	10
17	10
18	10
19	11
20	11
21	11
22	12
23	12
24	12
25	12
26	13
27	13
28	14
29	14
30	15

	Dry (%)	Comfortable (%)
1	99	1
2	99	1
3	99	1
4	99	1
5	99	1
6	99	1
7	99	1
8	99	1
9	99	1
10	99	1
11	99	1
12	99	1
13	99	1
14	99	1
15	99	1
16	99	1
17	99	1
18	99	1
19	99	1
20	99	1
21	99	1
22	99	1
23	99	1
24	99	1
25	99	1
26	99	1
27	99	1
28	100	0
29	100	0
30	100	0

	Avg high (°F)	Avg low (°F)
1	82	55
2	81	55
3	81	54
4	81	54
5	80	54
6	80	54
7	80	53
8	79	53
9	79	53
10	79	53
11	78	52
12	78	52
13	77	52
14	77	51
15	77	51
16	76	51
17	76	51
18	76	50
19	75	50
20	75	50
21	74	49
22	74	49
23	74	49
24	73	49
25	73	48
26	73	48
27	72	48
28	72	47
29	71	47
30	71	47

	Clearer (%)	Cloudier (%)
1	85	15
2	84	16
3	84	16
4	83	17
5	82	18
6	81	19
7	81	19
8	79	21
9	79	21
10	78	22
11	78	22
12	76	24
13	76	24
14	75	25
15	74	26
16	74	26
17	73	27
18	73	27
19	72	28
20	72	28
21	71	29
22	71	29
23	71	29
24	71	29
25	71	29
26	71	29
27	71	29
28	70	30
29	70	30
30	69	31

	Rain chance (%)
1	6
2	6
3	6
4	6
5	6
6	7
7	7
8	8
9	8
10	9
11	9
12	9
13	10
14	10
15	10
16	10
17	10
18	10
19	11
20	11
21	11
22	12
23	12
24	12
25	12
26	13
27	13
28	14
29	14
30	15

	Dry (%)	Comfortable (%)
1	99	1
2	99	1
3	99	1
4	99	1
5	99	1
6	99	1
7	99	1
8	99	1
9	99	1
10	99	1
11	99	1
12	99	1
13	99	1
14	99	1
15	99	1
16	99	1
17	99	1
18	99	1
19	99	1
20	99	1
21	99	1
22	99	1
23	99	1
24	99	1
25	99	1
26	99	1
27	99	1
28	100	0
29	100	0
30	100	0