Cortland weather in September

In September, Cortland sees average daytime highs of 69°F and overnight lows near 52°F, with 4.1 in of rain across 10.5 wet days and about 12.3 hours of daylight. It is the 4th-warmest and 5th-wettest month of the year here.

Highs ease over the month, from about 74°F in the first days to 65°F by the end. The sky is clear or mostly clear about 30% 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 Cortland's 1st-clearest and 9th-windiest month. For the whole year in context, see Cortland's year-round climate.

Daytime high
69°
4th warmest
Overnight low
52°
9th coldest
Rainfall
4.1 in
10.5 wet days
Daylight
12 h 18 min
5:51 AM – 6:08 PM
Cloud cover
59%
1st clearest
Wind
6 mph
9th windiest
Solar energy
4.02 kWh/m²
Travel score
6.3
out of 10

Cortland is city in New York, USA.

Density
1,865/km²
people per km²
Founded
1791

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

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 74°F in the first days to 65°F by the end.

A typical September day in Cortland reaches about 69°F in the afternoon and slips back to 52°F overnight — a 18°F spread between the day's warmth and the night's chill. On most days the high lands between 59°F and 79°F. Set against its neighbours, September runs about 7°F cooler than August and about 12°F warmer than October.

40°60°80°151015202530
Avg high (°F)Avg low (°F)
17456
27456
37456
47356
57355
67355
77355
87254
97254
107154
117153
127153
137153
147052
157052
166951
176951
186951
196850
206850
216850
226749
236749
246649
256648
266648
276548
286547
296447
306447

How September really feels in Cortland

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
0
heat index over the day's high
Days feeling ≤ 32°F
0
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.

Cortland weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 5th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan30° / 16°3.112.612.29.20.0
Feb32° / 17°2.710.99.510.30.0
Mar41° / 25°3.8138.211.60.3
Apr54° / 37°4.213.52.913.13.0
May65° / 47°4.013.90.214.45.4
Jun74° / 56°4.412.8015.16.3
Jul78° / 60°4.213014.86.3
Aug76° / 59°3.912.3013.76.6
Sep69° / 52°4.110.5012.36.3
Oct57° / 41°4.2130.610.83.8
Nov45° / 31°3.512.34.49.60.9
Dec35° / 23°3.613108.90.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 30% of the time in September, the clearest month of the year.

Beyond those clear spells, partly cloudy skies cover about 17% of September, with mostly cloudy or overcast conditions the remaining 53%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
15149
25149
35050
44951
54951
64852
74852
84852
94852
104753
114753
124654
134654
144555
154555
164555
174555
184555
194555
204654
214654
224654
234753
244753
254654
264753
274753
284654
294753
304753

Chance of precipitation in September

Any precipitation

Cortland gets around 4.1 in of rain over 10.5 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 39% on the wettest days. The odds climb toward the end of the month.

0%10%20%30%40%50%151015202530
Rain chance (%)
132
233
333
433
533
633
734
834
934
1034
1135
1235
1335
1435
1535
1635
1735
1835
1936
2036
2136
2236
2337
2437
2538
2638
2739
2839
2939
3039

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 59% of days. Sticky, muggy-or-worse air turns up on roughly 5% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)
140262311
241252211
342252210
444252110
545252010
64625199
74725189
84925188
95025178
105125177
115324167
125424166
135524156
145823145
155823145
165923135
176122134
186321124
196321124
206520123
216719113
226918112
237017112
247216102
257216102
26751591
27761491
28761491
29781381
30791281

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.

0246810151015202530
Wind speed (mph)Feels
16calm
26calm
36calm
46calm
56calm
66calm
76calm
86calm
96calm
106calm
116calm
126calm
136calm
146calm
156calm
166calm
176calm
186calm
197calm
207calm
217calm
227calm
237calm
247calm
257calm
267calm
277calm
287calm
297calm
307calm

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 5:34 AM to 6:06 AM, and sunset from 6:35 PM to 5:42 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.05:346:35
213.05:356:33
312.95:366:31
412.95:376:30
512.85:386:28
612.85:396:26
712.75:416:24
812.75:426:22
912.65:436:20
1012.65:446:19
1112.55:456:17
1212.55:466:15
1312.45:476:13
1412.45:486:11
1512.35:496:09
1612.35:516:08
1712.25:526:06
1812.25:536:04
1912.15:546:02
2012.15:556:00
2112.05:565:58
2212.05:575:56
2311.95:585:55
2411.95:595:53
2511.86:015:51
2611.86:025:49
2711.76:035:47
2811.76:045:45
2911.66:055:44
3011.66:065:42

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.02 kWh/m².

For context, solar energy here swings from a low near 1.31 kWh/m² to a high of 5.98 kWh/m² in June across the year — September's 4.02 kWh/m² falls in the middle.

024151015202530
Solar energy (kWh/m²)Level
14.6Bright
24.6Bright
34.5Bright
44.5Bright
54.5Bright
64.4Bright
74.4Bright
84.3Bright
94.3Bright
104.2Bright
114.2Bright
124.2Bright
134.1Bright
144.1Bright
154.0Bright
164.0Bright
174.0Moderate
183.9Moderate
193.9Moderate
203.9Moderate
213.8Moderate
223.8Moderate
233.7Moderate
243.7Moderate
253.6Moderate
263.6Moderate
273.5Moderate
283.5Moderate
293.4Moderate
303.4Moderate
Planning a trip in September

Is September a good time to visit Cortland?

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

6.3
Sightseeing
2nd-best month of the year
3.8
Beach & pool
4th-best month of the year

September is a reasonable time to visit Cortland for sightseeing.

What to pack for Cortland in September

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

In September, Cortland sees daytime highs around 69°F and nights near 52°F. Worth packing: rain gear. About 11 days see rain.

rain gear

UV index in Cortland 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 Cortland peaks around July 12 at about 8 (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.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJul 12UV 8Jan 1UV 2
UV index (midday)Level
Jan2Low
Feb2Moderate
Mar4Moderate
Apr5High
May8Very high
Jun8Very high
Jul9Very high
Aug6High
Sep6High
Oct3Moderate
Nov2Moderate
Dec2Low
Location & terrain

Where is Cortland?

Cortland sits at 42.6°N, 76.2°W, 1,129 ft above sea level, in United States. The nearest listed city is Ithaca, 19 mi away.

Topography around Cortland

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

Within 2 miles, the terrain around Cortland has only modest variations in elevation — a maximum elevation change of 614 ft around an average of 1,220 ft above sea level; within 10 miles, significant variations in elevation — a maximum elevation change of 1,178 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 1,847 ft.

The land around Cortland is covered by trees (43%) and grassland (28%) within 2 miles, trees (63%) and grassland (20%) within 10 miles, and trees (66%) within 50 miles.

2 miles
614 ft
10 miles
1,178 ft
50 miles
1,847 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Ithaca 19 mi · Auburn 30 mi · Syracuse 31 mi · Vestal 36 mi · Binghamton 37 mi · Cicero 40 mi · Clay 40 mi · Elmira 48 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
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

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 Cortland (42.6012°, -76.1805°, elevation 1,129 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).