Ithaca weather in September

In September, Ithaca sees average daytime highs of 70°F and overnight lows near 53°F, with 3.8 in of rain across 10.4 wet days and about 12.3 hours of daylight. It is the 4th-warmest and 4th-wettest month of the year here.

Highs ease over the month, from about 75°F in the first days to 66°F by the end. The sky is clear or mostly clear about 31% 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 Ithaca's 3rd-clearest and 9th-windiest month. For the whole year in context, see Ithaca's year-round climate.

Daytime high: 70°; 4th warmest
Overnight low: 53°; 9th coldest
Rainfall: 3.8 in; 10.4 wet days
Daylight: 12 h 18 min; 5:52 AM – 6:09 PM
Cloud cover: 58%; 3rd clearest
Wind: 6 mph; 9th windiest
Solar energy: 4 kWh/m²
Travel score: 6.4; out of 10

Ithaca is city in Tompkins County, New York, USA, enclosed by the town of the same name.

Density: 1,958/km²; people per km²
Founded: 1888

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

← August Ithaca 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 75°F in the first days to 66°F by the end.

A typical September day in Ithaca reaches about 70°F in the afternoon and slips back to 53°F overnight — a 17°F spread between the day's warmth and the night's chill. On most days the high lands between 60°F and 81°F. Set against its neighbours, September runs about 7°F cooler than August and about 12°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)	75	75	75	74	74	74	73	73	73	73	72	72	71	71	71	70	70	70	69	69	69	68	68	67	67	67	66	66	65	65
Avg low (°F)	58	58	57	57	57	57	56	56	56	55	55	55	54	54	53	53	53	52	52	52	51	51	51	50	50	50	49	49	49	48

	Avg high (°F)	Avg low (°F)
1	75	58
2	75	58
3	75	57
4	74	57
5	74	57
6	74	57
7	73	56
8	73	56
9	73	56
10	73	55
11	72	55
12	72	55
13	71	54
14	71	54
15	71	53
16	70	53
17	70	53
18	70	52
19	69	52
20	69	52
21	69	51
22	68	51
23	68	51
24	67	50
25	67	50
26	67	50
27	66	49
28	66	49
29	65	49
30	65	48

How September really feels in Ithaca

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.

Ithaca weather by month

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

Month	High / Low (°F)	Rainfall (inches)	Wet days	Snow days	Daylight (hours)	Travel score
Jan	31° / 18°	2.8	12	10.8	9.2	0.0
Feb	33° / 19°	2.5	10.4	8.4	10.3	0.0
Mar	42° / 26°	3.5	12.3	7.1	11.6	0.4
Apr	55° / 37°	3.9	13.3	2.6	13.1	3.2
May	66° / 48°	3.6	13.2	0.1	14.4	5.6
Jun	75° / 57°	3.9	11.7	0	15	6.5
Jul	79° / 62°	3.8	12.4	0	14.8	6.3
Aug	77° / 60°	3.4	11.3	0	13.7	6.7
Sep	70° / 53°	3.8	10.4	0	12.3	6.4
Oct	58° / 43°	4.1	13.1	0.5	10.8	4.0
Nov	46° / 33°	3.3	12.2	4.1	9.6	1.2
Dec	36° / 25°	3.4	12.5	9.1	8.9	0.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 31% 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 53%.

	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 (%)	52	51	51	50	49	49	49	48	48	47	47	45	46	46	45	45	45	45	45	45	46	47	47	46	47	47	47	46	46	46
Cloudier (%)	48	49	49	50	51	51	51	52	52	53	53	55	54	54	55	55	55	55	55	55	54	53	53	54	53	53	53	54	54	54

	Clearer (%)	Cloudier (%)
1	52	48
2	51	49
3	51	49
4	50	50
5	49	51
6	49	51
7	49	51
8	48	52
9	48	52
10	47	53
11	47	53
12	45	55
13	46	54
14	46	54
15	45	55
16	45	55
17	45	55
18	45	55
19	45	55
20	45	55
21	46	54
22	47	53
23	47	53
24	46	54
25	47	53
26	47	53
27	47	53
28	46	54
29	46	54
30	46	54

Chance of precipitation in September

Any precipitation

Ithaca gets around 3.8 in of rain over 10.4 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 35% and peaks near 41% 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 (%)	31	32	32	32	33	33	33	34	34	34	34	35	35	35	35	35	35	35	35	35	36	36	37	37	38	39	39	40	40	41

	Rain chance (%)
1	31
2	32
3	32
4	32
5	33
6	33
7	33
8	34
9	34
10	34
11	34
12	35
13	35
14	35
15	35
16	35
17	35
18	35
19	35
20	35
21	36
22	36
23	37
24	37
25	38
26	39
27	39
28	40
29	40
30	41

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 55% of days. Sticky, muggy-or-worse air turns up on roughly 6% of them.

	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 (%)	34	35	37	38	40	41	42	44	45	46	48	49	50	52	54	55	56	59	60	61	63	64	66	68	69	71	71	73	75	75
Comfortable (%)	28	28	28	27	28	27	27	27	27	27	26	26	26	25	25	24	24	23	22	21	21	20	19	18	18	17	17	16	15	15
Humid (%)	25	25	24	23	22	22	21	20	19	19	18	17	17	16	15	15	14	13	13	13	12	12	12	11	11	10	10	9	9	9
Muggy (%)	12	12	11	11	10	10	10	9	9	8	8	7	7	7	6	6	6	5	5	5	4	4	3	3	2	2	2	2	1	1

	Dry (%)	Comfortable (%)	Humid (%)	Muggy (%)
1	34	28	25	12
2	35	28	25	12
3	37	28	24	11
4	38	27	23	11
5	40	28	22	10
6	41	27	22	10
7	42	27	21	10
8	44	27	20	9
9	45	27	19	9
10	46	27	19	8
11	48	26	18	8
12	49	26	17	7
13	50	26	17	7
14	52	25	16	7
15	54	25	15	6
16	55	24	15	6
17	56	24	14	6
18	59	23	13	5
19	60	22	13	5
20	61	21	13	5
21	63	21	12	4
22	64	20	12	4
23	66	19	12	3
24	68	18	11	3
25	69	18	11	2
26	71	17	10	2
27	71	17	10	2
28	73	16	9	2
29	75	15	9	1
30	75	15	9	1

Wind in September

Winds average 6 mph in September.

Across September, daily wind ranges from about 6 mph on the calmest days to 7 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	6	6	6	6	6	6	6	6	6	6	6	6	6	7	7	7	7	7	7
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	6	calm
13	6	calm
14	6	calm
15	6	calm
16	6	calm
17	6	calm
18	6	calm
19	6	calm
20	6	calm
21	6	calm
22	6	calm
23	6	calm
24	6	calm
25	7	calm
26	7	calm
27	7	calm
28	7	calm
29	7	calm
30	7	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 5:35 AM to 6:07 AM, and sunset from 6:36 PM to 5:43 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)	5:35	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	6:00	6:01	6:02	6:03	6:04	6:05	6:06	6:07
Sunset (PM)	6:36	6:34	6:32	6:31	6:29	6:27	6:25	6:23	6:22	6:20	6:18	6:16	6:14	6:12	6:11	6:09	6:07	6:05	6:03	6:01	6:00	5:58	5:56	5:54	5:52	5:50	5:49	5:47	5:45	5:43

	Daylight (h)	Sunrise (AM)	Sunset (PM)
1	13.0	5:35	6:36
2	13.0	5:37	6:34
3	12.9	5:38	6:32
4	12.9	5:39	6:31
5	12.8	5:40	6:29
6	12.8	5:41	6:27
7	12.7	5:42	6:25
8	12.7	5:43	6:23
9	12.6	5:44	6:22
10	12.6	5:45	6:20
11	12.5	5:46	6:18
12	12.5	5:47	6:16
13	12.4	5:49	6:14
14	12.4	5:50	6:12
15	12.3	5:51	6:11
16	12.3	5:52	6:09
17	12.2	5:53	6:07
18	12.2	5:54	6:05
19	12.1	5:55	6:03
20	12.1	5:56	6:01
21	12.0	5:57	6:00
22	12.0	5:58	5:58
23	11.9	6:00	5:56
24	11.9	6:01	5:54
25	11.8	6:02	5:52
26	11.8	6:03	5:50
27	11.7	6:04	5:49
28	11.7	6:05	5:47
29	11.6	6:06	5:45
30	11.6	6:07	5:43

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4 kWh/m².

For context, solar energy here swings from a low near 1.31 kWh/m² to a high of 5.99 kWh/m² in June across the year — September's 4 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)	4.6	4.6	4.5	4.5	4.4	4.4	4.3	4.3	4.3	4.2	4.2	4.1	4.1	4.1	4.0	4.0	4.0	3.9	3.9	3.9	3.8	3.8	3.7	3.7	3.6	3.6	3.5	3.5	3.4	3.4
Level	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate

	Solar energy (kWh/m²)	Level
1	4.6	Bright
2	4.6	Bright
3	4.5	Bright
4	4.5	Bright
5	4.4	Bright
6	4.4	Bright
7	4.3	Bright
8	4.3	Bright
9	4.3	Bright
10	4.2	Bright
11	4.2	Bright
12	4.1	Bright
13	4.1	Bright
14	4.1	Bright
15	4.0	Bright
16	4.0	Bright
17	4.0	Moderate
18	3.9	Moderate
19	3.9	Moderate
20	3.9	Moderate
21	3.8	Moderate
22	3.8	Moderate
23	3.7	Moderate
24	3.7	Moderate
25	3.6	Moderate
26	3.6	Moderate
27	3.5	Moderate
28	3.5	Moderate
29	3.4	Moderate
30	3.4	Moderate

Planning a trip in September

Is September a good time to visit Ithaca?

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

6.4

Sightseeing

3rd-best month of the year

4.1

Beach & pool

4th-best month of the year

September is a reasonable time to visit Ithaca for sightseeing.

What to pack for Ithaca in September

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

In September, Ithaca sees daytime highs around 70°F and nights near 53°F. Worth packing: rain gear. About 10 days see rain.

rain gear

UV index in Ithaca 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 Ithaca peaks around July 11 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near January 1 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	2	4	5	8	8	9	6	6	3	2	2
Level	Low	Moderate	Moderate	High	Very high	Very high	Very high	High	High	Moderate	Moderate	Low

	UV index (midday)	Level
Jan	2	Low
Feb	2	Moderate
Mar	4	Moderate
Apr	5	High
May	8	Very high
Jun	8	Very high
Jul	9	Very high
Aug	6	High
Sep	6	High
Oct	3	Moderate
Nov	2	Moderate
Dec	2	Low

Location & terrain

Where is Ithaca?

Ithaca sits at 42.4°N, 76.5°W, 410 ft above sea level, in United States. The nearest listed city is Cortland, 19 mi away.

Topography around Ithaca

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

Within 2 miles, the terrain around Ithaca has significant variations in elevation — a maximum elevation change of 919 ft around an average of 686 ft above sea level; within 10 miles, significant variations in elevation — a maximum elevation change of 1,772 ft; within 50 miles, large variations in elevation — a maximum elevation change of 2,060 ft.

The land around Ithaca is covered by trees (59%) within 2 miles, trees (65%) and grassland (20%) within 10 miles, and trees (66%) within 50 miles.

2 miles

919 ft

trees 59%

10 miles

1,772 ft

trees 65%

50 miles

2,060 ft

trees 66%

treesgrasslandcroplandartificial surfaceswater

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

September weather nearby: Cortland 19 mi · Elmira 29 mi · Vestal 34 mi · Auburn 34 mi · Binghamton 38 mi · Syracuse 45 mi · Clay 54 mi · Cicero 54 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 Ithaca (42.4406°, -76.4966°, elevation 410 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. 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	75	58
2	75	58
3	75	57
4	74	57
5	74	57
6	74	57
7	73	56
8	73	56
9	73	56
10	73	55
11	72	55
12	72	55
13	71	54
14	71	54
15	71	53
16	70	53
17	70	53
18	70	52
19	69	52
20	69	52
21	69	51
22	68	51
23	68	51
24	67	50
25	67	50
26	67	50
27	66	49
28	66	49
29	65	49
30	65	48

	Clearer (%)	Cloudier (%)
1	52	48
2	51	49
3	51	49
4	50	50
5	49	51
6	49	51
7	49	51
8	48	52
9	48	52
10	47	53
11	47	53
12	45	55
13	46	54
14	46	54
15	45	55
16	45	55
17	45	55
18	45	55
19	45	55
20	45	55
21	46	54
22	47	53
23	47	53
24	46	54
25	47	53
26	47	53
27	47	53
28	46	54
29	46	54
30	46	54

	Rain chance (%)
1	31
2	32
3	32
4	32
5	33
6	33
7	33
8	34
9	34
10	34
11	34
12	35
13	35
14	35
15	35
16	35
17	35
18	35
19	35
20	35
21	36
22	36
23	37
24	37
25	38
26	39
27	39
28	40
29	40
30	41

	Dry (%)	Comfortable (%)	Humid (%)	Muggy (%)
1	34	28	25	12
2	35	28	25	12
3	37	28	24	11
4	38	27	23	11
5	40	28	22	10
6	41	27	22	10
7	42	27	21	10
8	44	27	20	9
9	45	27	19	9
10	46	27	19	8
11	48	26	18	8
12	49	26	17	7
13	50	26	17	7
14	52	25	16	7
15	54	25	15	6
16	55	24	15	6
17	56	24	14	6
18	59	23	13	5
19	60	22	13	5
20	61	21	13	5
21	63	21	12	4
22	64	20	12	4
23	66	19	12	3
24	68	18	11	3
25	69	18	11	2
26	71	17	10	2
27	71	17	10	2
28	73	16	9	2
29	75	15	9	1
30	75	15	9	1

	Avg high (°F)	Avg low (°F)
1	75	58
2	75	58
3	75	57
4	74	57
5	74	57
6	74	57
7	73	56
8	73	56
9	73	56
10	73	55
11	72	55
12	72	55
13	71	54
14	71	54
15	71	53
16	70	53
17	70	53
18	70	52
19	69	52
20	69	52
21	69	51
22	68	51
23	68	51
24	67	50
25	67	50
26	67	50
27	66	49
28	66	49
29	65	49
30	65	48

	Clearer (%)	Cloudier (%)
1	52	48
2	51	49
3	51	49
4	50	50
5	49	51
6	49	51
7	49	51
8	48	52
9	48	52
10	47	53
11	47	53
12	45	55
13	46	54
14	46	54
15	45	55
16	45	55
17	45	55
18	45	55
19	45	55
20	45	55
21	46	54
22	47	53
23	47	53
24	46	54
25	47	53
26	47	53
27	47	53
28	46	54
29	46	54
30	46	54

	Rain chance (%)
1	31
2	32
3	32
4	32
5	33
6	33
7	33
8	34
9	34
10	34
11	34
12	35
13	35
14	35
15	35
16	35
17	35
18	35
19	35
20	35
21	36
22	36
23	37
24	37
25	38
26	39
27	39
28	40
29	40
30	41

	Dry (%)	Comfortable (%)	Humid (%)	Muggy (%)
1	34	28	25	12
2	35	28	25	12
3	37	28	24	11
4	38	27	23	11
5	40	28	22	10
6	41	27	22	10
7	42	27	21	10
8	44	27	20	9
9	45	27	19	9
10	46	27	19	8
11	48	26	18	8
12	49	26	17	7
13	50	26	17	7
14	52	25	16	7
15	54	25	15	6
16	55	24	15	6
17	56	24	14	6
18	59	23	13	5
19	60	22	13	5
20	61	21	13	5
21	63	21	12	4
22	64	20	12	4
23	66	19	12	3
24	68	18	11	3
25	69	18	11	2
26	71	17	10	2
27	71	17	10	2
28	73	16	9	2
29	75	15	9	1
30	75	15	9	1

	Avg high (°F)	Avg low (°F)
1	75	58
2	75	58
3	75	57
4	74	57
5	74	57
6	74	57
7	73	56
8	73	56
9	73	56
10	73	55
11	72	55
12	72	55
13	71	54
14	71	54
15	71	53
16	70	53
17	70	53
18	70	52
19	69	52
20	69	52
21	69	51
22	68	51
23	68	51
24	67	50
25	67	50
26	67	50
27	66	49
28	66	49
29	65	49
30	65	48

	Clearer (%)	Cloudier (%)
1	52	48
2	51	49
3	51	49
4	50	50
5	49	51
6	49	51
7	49	51
8	48	52
9	48	52
10	47	53
11	47	53
12	45	55
13	46	54
14	46	54
15	45	55
16	45	55
17	45	55
18	45	55
19	45	55
20	45	55
21	46	54
22	47	53
23	47	53
24	46	54
25	47	53
26	47	53
27	47	53
28	46	54
29	46	54
30	46	54

	Rain chance (%)
1	31
2	32
3	32
4	32
5	33
6	33
7	33
8	34
9	34
10	34
11	34
12	35
13	35
14	35
15	35
16	35
17	35
18	35
19	35
20	35
21	36
22	36
23	37
24	37
25	38
26	39
27	39
28	40
29	40
30	41

	Dry (%)	Comfortable (%)	Humid (%)	Muggy (%)
1	34	28	25	12
2	35	28	25	12
3	37	28	24	11
4	38	27	23	11
5	40	28	22	10
6	41	27	22	10
7	42	27	21	10
8	44	27	20	9
9	45	27	19	9
10	46	27	19	8
11	48	26	18	8
12	49	26	17	7
13	50	26	17	7
14	52	25	16	7
15	54	25	15	6
16	55	24	15	6
17	56	24	14	6
18	59	23	13	5
19	60	22	13	5
20	61	21	13	5
21	63	21	12	4
22	64	20	12	4
23	66	19	12	3
24	68	18	11	3
25	69	18	11	2
26	71	17	10	2
27	71	17	10	2
28	73	16	9	2
29	75	15	9	1
30	75	15	9	1