Altamont weather in September

In September, Altamont sees average daytime highs of 76°F and overnight lows near 48°F, with 0.5 in of rain across 2.6 wet days and about 12.3 hours of daylight. It is the 3rd-warmest and 10th-wettest month of the year here.

Highs ease over the month, from about 80°F in the first days to 71°F by the end. The sky is clear or mostly clear about 69% of the time in September, and the air most often feels dry.

Daylight stretches from about 13 hours at the start of September to 11 h 36 min by month's end. Set against the rest of the year, September is Altamont's 3rd-clearest and 10th-windiest month. For the whole year in context, see Altamont's year-round climate.

Daytime high: 76°; 3rd warmest
Overnight low: 48°; 10th coldest
Rainfall: 0.5 in; 2.6 wet days
Daylight: 12 h 18 min; 5:53 AM – 6:10 PM
Cloud cover: 27%; 3rd clearest
Wind: 4 mph; 10th windiest
Solar energy: 5.63 kWh/m²
Travel score: 8.6; out of 10

Altamont is unincorporated community in Klamath County, Oregon, United States.

Density: 918/km²; people per km²

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

← August Altamont 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 80°F in the first days to 71°F by the end.

A typical September day in Altamont reaches about 76°F in the afternoon and slips back to 48°F overnight — a 28°F spread between the day's warmth and the night's chill. On most days the high lands between 62°F and 86°F. Set against its neighbours, September runs about 8°F cooler than August and about 13°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)	80	80	80	80	79	79	79	78	78	78	77	77	76	76	76	75	75	75	74	74	74	74	73	73	73	72	72	71	71	70
Avg low (°F)	52	51	51	51	51	51	50	50	50	49	49	49	49	49	48	48	48	47	47	47	47	46	46	46	46	45	45	45	44	44

	Avg high (°F)	Avg low (°F)
1	80	52
2	80	51
3	80	51
4	80	51
5	79	51
6	79	51
7	79	50
8	78	50
9	78	50
10	78	49
11	77	49
12	77	49
13	76	49
14	76	49
15	76	48
16	75	48
17	75	48
18	75	47
19	74	47
20	74	47
21	74	47
22	74	46
23	73	46
24	73	46
25	73	46
26	72	45
27	72	45
28	71	45
29	71	44
30	70	44

How September really feels in Altamont

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.

Altamont weather by month

How September compares with the rest of the year at a glance. September is the 3rd-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	39° / 26°	3.2	11.8	9.5	9.3	0.0
Feb	43° / 27°	2.5	10	8.4	10.3	0.4
Mar	48° / 30°	2.8	12.1	8	11.6	1.8
Apr	55° / 34°	2.0	10.1	4.5	13.1	3.5
May	65° / 41°	1.7	8.3	1.1	14.4	6.2
Jun	74° / 47°	0.9	4.7	0.1	15	7.9
Jul	84° / 55°	0.3	2.1	0	14.8	7.1
Aug	83° / 55°	0.4	1.8	0	13.7	7.4
Sep	76° / 48°	0.5	2.6	0	12.3	8.6
Oct	62° / 40°	1.4	5.7	1	10.8	6.1
Nov	47° / 32°	2.7	9.7	5.5	9.6	1.4
Dec	38° / 26°	3.9	12.4	10.4	9	0.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 69% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 13% of September, with mostly cloudy or overcast conditions the remaining 18%. 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 (%)	90	89	89	89	88	88	87	86	86	85	84	83	83	82	81	81	80	80	80	80	79	79	79	78	78	77	77	76	76	75
Cloudier (%)	10	11	11	11	12	12	13	14	14	15	16	17	17	18	19	19	20	20	20	20	21	21	21	22	22	23	23	24	24	25

	Clearer (%)	Cloudier (%)
1	90	10
2	89	11
3	89	11
4	89	11
5	88	12
6	88	12
7	87	13
8	86	14
9	86	14
10	85	15
11	84	16
12	83	17
13	83	17
14	82	18
15	81	19
16	81	19
17	80	20
18	80	20
19	80	20
20	80	20
21	79	21
22	79	21
23	79	21
24	78	22
25	78	22
26	77	23
27	77	23
28	76	24
29	76	24
30	75	25

Chance of precipitation in September

Any precipitation

Altamont gets around 0.5 in of rain over 2.6 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 9% and peaks near 11% on the wettest days.

	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 (%)	5	5	5	6	6	6	6	7	7	8	8	9	9	9	9	10	10	10	10	10	10	10	10	10	10	10	11	11	11	11

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

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 100% 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 (%)	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100

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

Wind in September

Winds average 4 mph in September.

Across September, daily wind ranges from about 4 mph on the calmest days to 5 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)	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	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	4	calm
2	4	calm
3	4	calm
4	4	calm
5	4	calm
6	4	calm
7	4	calm
8	4	calm
9	4	calm
10	4	calm
11	4	calm
12	4	calm
13	4	calm
14	4	calm
15	4	calm
16	4	calm
17	4	calm
18	4	calm
19	4	calm
20	4	calm
21	4	calm
22	4	calm
23	4	calm
24	4	calm
25	4	calm
26	4	calm
27	4	calm
28	5	calm
29	5	calm
30	5	calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 hours at the start of September to 11 h 36 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 84 minutes over September. Sunrise moves from 5:37 AM to 6:08 AM, and sunset from 6:37 PM to 5:44 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)	13.0	13.0	12.9	12.9	12.8	12.8	12.7	12.7	12.6	12.6	12.5	12.5	12.4	12.4	12.3	12.3	12.2	12.2	12.1	12.1	12.0	12.0	11.9	11.9	11.8	11.8	11.7	11.7	11.6	11.6
Sunrise (AM)	5:37	5:38	5:39	5:40	5:41	5:42	5:43	5:44	5:45	5:46	5:47	5:49	5:50	5:51	5:52	5:53	5:54	5:55	5:56	5:57	5:58	5:59	6:01	6:02	6:03	6:04	6:05	6:06	6:07	6:08
Sunset (PM)	6:37	6:35	6:33	6:31	6:30	6:28	6:26	6:24	6:22	6:21	6:19	6:17	6:15	6:13	6:12	6:10	6:08	6:06	6:04	6:02	6:01	5:59	5:57	5:55	5:53	5:51	5:50	5:48	5:46	5:44

	Daylight (h)	Sunrise (AM)	Sunset (PM)
1	13.0	5:37	6:37
2	13.0	5:38	6:35
3	12.9	5:39	6:33
4	12.9	5:40	6:31
5	12.8	5:41	6:30
6	12.8	5:42	6:28
7	12.7	5:43	6:26
8	12.7	5:44	6:24
9	12.6	5:45	6:22
10	12.6	5:46	6:21
11	12.5	5:47	6:19
12	12.5	5:49	6:17
13	12.4	5:50	6:15
14	12.4	5:51	6:13
15	12.3	5:52	6:12
16	12.3	5:53	6:10
17	12.2	5:54	6:08
18	12.2	5:55	6:06
19	12.1	5:56	6:04
20	12.1	5:57	6:02
21	12.0	5:58	6:01
22	12.0	5:59	5:59
23	11.9	6:01	5:57
24	11.9	6:02	5:55
25	11.8	6:03	5:53
26	11.8	6:04	5:51
27	11.7	6:05	5:50
28	11.7	6:06	5:48
29	11.6	6:07	5:46
30	11.6	6:08	5:44

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 5.63 kWh/m².

For context, solar energy here swings from a low near 1.73 kWh/m² to a high of 8.03 kWh/m² in July across the year — September's 5.63 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)	6.5	6.4	6.4	6.3	6.3	6.2	6.1	6.1	6.0	6.0	5.9	5.8	5.8	5.7	5.6	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
Level	Intense	Intense	Intense	Intense	Intense	Intense	Intense	Intense	Intense	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	6.5	Intense
2	6.4	Intense
3	6.4	Intense
4	6.3	Intense
5	6.3	Intense
6	6.2	Intense
7	6.1	Intense
8	6.1	Intense
9	6.0	Intense
10	6.0	Bright
11	5.9	Bright
12	5.8	Bright
13	5.8	Bright
14	5.7	Bright
15	5.6	Bright
16	5.6	Bright
17	5.5	Bright
18	5.5	Bright
19	5.4	Bright
20	5.3	Bright
21	5.3	Bright
22	5.2	Bright
23	5.2	Bright
24	5.1	Bright
25	5.0	Bright
26	5.0	Bright
27	4.9	Bright
28	4.8	Bright
29	4.8	Bright
30	4.7	Bright

Planning a trip in September

Hazard calendar for Altamont

In seasonPeak

None of Altamont's seasonal hazards are active in September. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do peak.

Altamont's rainy season runs November–April, when most of the year's rain falls.

Rainy season

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Is September a good time to visit Altamont?

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

8.6

Sightseeing

1st-best month of the year

7.1

Beach & pool

3rd-best month of the year

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

What to pack for Altamont in September

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

In September, Altamont sees daytime highs around 76°F and nights near 48°F. Worth packing: light clothes and sun protection.

light clothessun protection

UV index in Altamont in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 6 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Altamont peaks around July 11 at about 10 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 12 at about 2 (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	3	5	6	9	9	10	8	6	5	2	2
Level	Moderate	Moderate	High	High	Very high	Very high	Very high	Very high	High	Moderate	Low	Low

	UV index (midday)	Level
Jan	2	Moderate
Feb	3	Moderate
Mar	5	High
Apr	6	High
May	9	Very high
Jun	9	Very high
Jul	10	Very high
Aug	8	Very high
Sep	6	High
Oct	5	Moderate
Nov	2	Low
Dec	2	Low

Air quality in Altamont 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 Altamont is worst in July — around 40 µg/m³ PM2.5 (poor), about 7.4× the cleanest month (January, 5 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)	5	8	9	14	9	7	40	33	38	10	8	9
Level	Good	Good	Good	Moderate	Good	Good	Poor	Moderate	Poor	Good	Good	Good

	PM2.5 (µg/m³)	Level
Jan	5	Good
Feb	8	Good
Mar	9	Good
Apr	14	Moderate
May	9	Good
Jun	7	Good
Jul	40	Poor
Aug	33	Moderate
Sep	38	Poor
Oct	10	Good
Nov	8	Good
Dec	9	Good

Location & terrain

Where is Altamont?

Altamont sits at 42.2°N, 121.7°W, 4,144 ft above sea level, in United States. The nearest listed city is Klamath Falls, 2.5 mi away.

Topography around Altamont

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

Within 2 miles, the terrain around Altamont has significant variations in elevation — a maximum elevation change of 830 ft around an average of 4,177 ft above sea level; within 10 miles, large variations in elevation — a maximum elevation change of 2,415 ft; within 50 miles, very significant variations in elevation — a maximum elevation change of 7,792 ft.

The land around Altamont is covered by artificial surfaces (42%) and grassland (41%) within 2 miles, grassland (50%) and trees (27%) within 10 miles, and trees (57%) and grassland (36%) within 50 miles.

2 miles

830 ft

artificial surfaces 42%

10 miles

2,415 ft

grassland 50%

50 miles

7,792 ft

trees 57%

treesgrasslandcroplandartificial surfacesbare terrainwater

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

September weather nearby: Klamath Falls 2.5 mi · Ashland 50 mi · Medford 59 mi · Central Point 62 mi · Grants Pass 83 mi · Roseburg 107 mi · Redding 117 mi · Bend 130 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 Altamont (42.2068°, -121.7372°, elevation 4,144 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	80	52
2	80	51
3	80	51
4	80	51
5	79	51
6	79	51
7	79	50
8	78	50
9	78	50
10	78	49
11	77	49
12	77	49
13	76	49
14	76	49
15	76	48
16	75	48
17	75	48
18	75	47
19	74	47
20	74	47
21	74	47
22	74	46
23	73	46
24	73	46
25	73	46
26	72	45
27	72	45
28	71	45
29	71	44
30	70	44

	Clearer (%)	Cloudier (%)
1	90	10
2	89	11
3	89	11
4	89	11
5	88	12
6	88	12
7	87	13
8	86	14
9	86	14
10	85	15
11	84	16
12	83	17
13	83	17
14	82	18
15	81	19
16	81	19
17	80	20
18	80	20
19	80	20
20	80	20
21	79	21
22	79	21
23	79	21
24	78	22
25	78	22
26	77	23
27	77	23
28	76	24
29	76	24
30	75	25

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

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

	Avg high (°F)	Avg low (°F)
1	80	52
2	80	51
3	80	51
4	80	51
5	79	51
6	79	51
7	79	50
8	78	50
9	78	50
10	78	49
11	77	49
12	77	49
13	76	49
14	76	49
15	76	48
16	75	48
17	75	48
18	75	47
19	74	47
20	74	47
21	74	47
22	74	46
23	73	46
24	73	46
25	73	46
26	72	45
27	72	45
28	71	45
29	71	44
30	70	44

	Clearer (%)	Cloudier (%)
1	90	10
2	89	11
3	89	11
4	89	11
5	88	12
6	88	12
7	87	13
8	86	14
9	86	14
10	85	15
11	84	16
12	83	17
13	83	17
14	82	18
15	81	19
16	81	19
17	80	20
18	80	20
19	80	20
20	80	20
21	79	21
22	79	21
23	79	21
24	78	22
25	78	22
26	77	23
27	77	23
28	76	24
29	76	24
30	75	25

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

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

	Avg high (°F)	Avg low (°F)
1	80	52
2	80	51
3	80	51
4	80	51
5	79	51
6	79	51
7	79	50
8	78	50
9	78	50
10	78	49
11	77	49
12	77	49
13	76	49
14	76	49
15	76	48
16	75	48
17	75	48
18	75	47
19	74	47
20	74	47
21	74	47
22	74	46
23	73	46
24	73	46
25	73	46
26	72	45
27	72	45
28	71	45
29	71	44
30	70	44

	Clearer (%)	Cloudier (%)
1	90	10
2	89	11
3	89	11
4	89	11
5	88	12
6	88	12
7	87	13
8	86	14
9	86	14
10	85	15
11	84	16
12	83	17
13	83	17
14	82	18
15	81	19
16	81	19
17	80	20
18	80	20
19	80	20
20	80	20
21	79	21
22	79	21
23	79	21
24	78	22
25	78	22
26	77	23
27	77	23
28	76	24
29	76	24
30	75	25

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

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