Norwalk weather in September

In September, Norwalk sees average daytime highs of 73°F and overnight lows near 58°F, with 3.1 in of rain across 9.7 wet days and about 12.3 hours of daylight. It is the 4th-warmest and 11th-wettest month of the year here.

Highs ease over the month, from about 77°F in the first days to 68°F by the end. The sky is clear or mostly clear about 38% 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 Norwalk's 1st-clearest and 9th-windiest month. For the whole year in context, see Norwalk's year-round climate.

Daytime high
73°
4th warmest
Overnight low
58°
9th coldest
Rainfall
3.1 in
9.7 wet days
Daylight
12 h 18 min
6:17 AM – 6:33 PM
Cloud cover
52%
1st clearest
Wind
8 mph
9th windiest
Solar energy
4.43 kWh/m²
Travel score
6.9
out of 10

Norwalk is city in and the county seat of Huron County, Ohio, United States.

Density
710/km²
people per km²
Founded
1817

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 77°F in the first days to 68°F by the end.

A typical September day in Norwalk reaches about 73°F in the afternoon and slips back to 58°F overnight — a 15°F spread between the day's warmth and the night's chill. On most days the high lands between 63°F and 83°F. Set against its neighbours, September runs about 6°F cooler than August and about 12°F warmer than October.

40°50°60°70°80°151015202530
Avg high (°F)Avg low (°F)
17763
27763
37763
47662
57662
67662
77661
87561
97561
107560
117460
127460
137459
147459
157358
167358
177358
187257
197257
207157
217156
227156
237055
247055
257055
266954
276954
286854
296853
306853

How September really feels in Norwalk

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.

Norwalk weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 11th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan33° / 22°3.311.77.39.40.0
Feb36° / 23°2.69.85.810.30.0
Mar44° / 30°3.511.34.311.70.8
Apr57° / 42°4.313.11.213.13.6
May68° / 53°4.213.4014.35.7
Jun77° / 63°4.212.9014.96.3
Jul81° / 67°3.612014.76.3
Aug79° / 65°3.511.2013.76.6
Sep73° / 58°3.19.7012.36.9
Oct61° / 47°3.210.90.110.95.0
Nov49° / 37°3.410.81.99.71.8
Dec38° / 28°3.411.15.39.10.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 38% 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 45%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
16139
26139
36139
46040
56040
66040
75941
85842
95842
105743
115644
125545
135545
145446
155446
165446
175446
185446
195248
205248
215248
225347
235347
245347
255248
265248
275149
285149
295149
305149

Chance of precipitation in September

Any precipitation

Norwalk gets around 3.1 in of rain over 9.7 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 32% and peaks near 34% on the wettest days.

0%10%20%30%40%151015202530
Rain chance (%)
133
233
333
433
533
633
733
833
932
1032
1132
1232
1331
1431
1531
1631
1731
1831
1931
2031
2131
2231
2332
2432
2533
2634
2734
2834
2934
3034

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 44% of days. Sticky, muggy-or-worse air turns up on roughly 14% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1202625245
2212724235
3222724225
4242823214
5252823204
6272823193
7282822183
8302822173
9322822162
10332821152
11352721152
12372721141
13392621131
14412620121
15432519121
16452519111
17472418100
18492417100
1951231790
2052231690
2155221580
2256221480
2359211370
2460201370
2561201270
2663191260
2765181160
2865181160
2968171050
3069161050

Wind in September

Winds average 8 mph in September.

Across September, daily wind ranges from about 8 mph on the calmest days to 9 mph at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (mph)Feels
18light breeze
28light breeze
38light breeze
48light breeze
58light breeze
68light breeze
78light breeze
88light breeze
98light breeze
108light breeze
118light breeze
128light breeze
138light breeze
148light breeze
158light breeze
168light breeze
178light breeze
188light breeze
199light breeze
209light breeze
219light breeze
229light breeze
239light breeze
249light breeze
259light breeze
269light breeze
279light breeze
289light breeze
299light breeze
309light breeze

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 6:01 AM to 6:31 AM, and sunset from 6:59 PM to 6:08 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.06:016:59
212.96:026:57
312.96:036:56
412.86:046:54
512.86:056:52
612.76:066:51
712.76:076:49
812.66:086:47
912.66:096:45
1012.66:106:44
1112.56:116:42
1212.56:136:40
1312.46:146:38
1412.46:156:36
1512.36:166:35
1612.36:176:33
1712.26:186:31
1812.26:196:29
1912.16:206:28
2012.16:216:26
2112.06:226:24
2212.06:236:22
2311.96:246:20
2411.96:256:19
2511.86:266:17
2611.86:276:15
2711.86:286:13
2811.76:296:12
2911.76:306:10
3011.66:316:08

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.43 kWh/m².

For context, solar energy here swings from a low near 1.51 kWh/m² to a high of 6.42 kWh/m² in June across the year — September's 4.43 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
15.0Bright
25.0Bright
34.9Bright
44.9Bright
54.8Bright
64.8Bright
74.8Bright
84.7Bright
94.7Bright
104.7Bright
114.6Bright
124.6Bright
134.5Bright
144.5Bright
154.5Bright
164.4Bright
174.4Bright
184.3Bright
194.3Bright
204.3Bright
214.2Bright
224.2Bright
234.1Bright
244.1Bright
254.0Bright
264.0Moderate
273.9Moderate
283.9Moderate
293.8Moderate
303.8Moderate
Planning a trip in September

Is September a good time to visit Norwalk?

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

6.9
Sightseeing
1st-best month of the year
5.1
Beach & pool
4th-best month of the year

September is a reasonable time to visit Norwalk for sightseeing.

What to pack for Norwalk in September

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

In September, Norwalk sees daytime highs around 73°F and nights near 58°F. Worth packing: light clothes and rain gear. About 10 days see rain.

light clothesrain gear

Sea temperature near Norwalk in September

The nearest coast averages about 71°F in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 27 mi away) is warmest in August at about 75°F and coldest in February near 33°F.

It's comfortable for a long swim from Jun 21 to Sep 23 — about 3.1 months when the water holds above 68°F.

30°40°50°60°70°80°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°F)Comfort
Jan34Bracing
Feb33Bracing
Mar35Bracing
Apr42Bracing
May54Bracing
Jun67Cool
Jul75Refreshing
Aug75Warm
Sep71Refreshing
Oct60Cool
Nov48Bracing
Dec39Bracing

UV index in Norwalk 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 Norwalk peaks around June 19 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 at about 1 (low).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJun 19UV 9Dec 22UV 1
UV index (midday)Level
Jan2Low
Feb2Moderate
Mar5Moderate
Apr6High
May8Very high
Jun10Very high
Jul9Very high
Aug7Very high
Sep6High
Oct3Moderate
Nov2Moderate
Dec1Low

Air quality in Norwalk 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 Norwalk is worst in July — around 16 µg/m³ PM2.5 (moderate), about 2.2× the cleanest month (October, 8 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1016 µg/m³Oct 248 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb11Good
Mar13Moderate
Apr13Moderate
May15Moderate
Jun16Moderate
Jul16Moderate
Aug14Moderate
Sep11Good
Oct8Good
Nov8Good
Dec8Good
Location & terrain

Where is Norwalk?

Norwalk sits at 41.2°N, 82.6°W, 719 ft above sea level, in United States. The nearest listed city is Sandusky, 15 mi away.

Topography around Norwalk

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

Within 2 miles, the terrain around Norwalk has only modest variations in elevation — a maximum elevation change of 253 ft around an average of 735 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 528 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 1,102 ft.

The land around Norwalk is covered by trees (44%) and grassland (21%) within 2 miles, cropland (63%) and trees (24%) within 10 miles, and cropland (40%), water (27%) and trees (21%) within 50 miles.

2 miles
253 ft
10 miles
528 ft
50 miles
1,102 ft
treesgrasslandcroplandartificial surfaceswater
September weather nearby: Sandusky 15 mi · Lorain 27 mi · Fremont 27 mi · Elyria 28 mi · Ashland 30 mi · Tiffin 30 mi · North Ridgeville 32 mi · Avon 34 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 Norwalk (41.2426°, -82.6157°, elevation 719 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. Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. 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).