Wilmette weather in May

In May, Wilmette sees average daytime highs of 65°F and overnight lows near 51°F, with 4.1 in of rain across 12 wet days and about 14.4 hours of daylight. It is the 5th-warmest and 2nd-wettest month of the year here.

Highs climb over the month, from about 60°F in the first days to 70°F by the end. The sky is clear or mostly clear about 28% of the time in May, and the air most often feels dry.

Daylight stretches from about 13 h 48 min at the start of May to 14 h 48 min by month's end. Set against the rest of the year, May is Wilmette's 6th-clearest and 8th-windiest month. For the whole year in context, see Wilmette's year-round climate.

Daytime high
65°
5th warmest
Overnight low
51°
8th coldest
Rainfall
4.1 in
12 wet days
Daylight
14 h 24 min
4:36 AM – 6:58 PM
Cloud cover
63%
6th clearest
Wind
10 mph
8th windiest
Solar energy
5.96 kWh/m²
Travel score
5.5
out of 10

Wilmette is village in Cook County, Illinois, United States.

Density
1,956/km²
people per km²
Founded
1872

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

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 60°F in the first days to 70°F by the end.

A typical May day in Wilmette reaches about 65°F in the afternoon and slips back to 51°F overnight — a 14°F spread between the day's warmth and the night's chill. On most days the high lands between 53°F and 78°F. Set against its neighbours, May runs about 11°F warmer than April and about 11°F cooler than June.

40°60°80°151015202531
Avg high (°F)Avg low (°F)
15945
25946
36046
46047
56147
66147
76148
86248
96248
106349
116349
126349
136450
146450
156450
166551
176551
186552
196652
206652
216753
226753
236754
246854
256855
266955
276955
286956
297056
307056
317157

How May really feels in Wilmette

Once humidity and wind are folded in, May 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

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

Wilmette weather by month

How May compares with the rest of the year at a glance. May is the 5th-warmest and 2nd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan31° / 20°2.39.16.39.30.0
Feb34° / 22°2.07.2510.30.0
Mar43° / 30°2.6103.111.70.6
Apr54° / 40°4.211.91.113.13.0
May65° / 51°4.112014.45.5
Jun76° / 63°3.611.90156.4
Jul81° / 68°3.411.3014.76.3
Aug79° / 67°3.610.7013.76.7
Sep73° / 59°2.98.9012.37.0
Oct60° / 47°3.39.40.110.85.0
Nov47° / 36°2.68.81.29.61.5
Dec36° / 26°2.38.84.490.0

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 28% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 15% of May, with mostly cloudy or overcast conditions the remaining 57%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13862
23763
33862
43961
53961
63961
73961
84060
94159
104258
114258
124357
134357
144357
154555
164555
174555
184555
194555
204654
214753
224753
234654
244654
254654
264654
274654
284555
294555
304555
314555

Chance of precipitation in May

Any precipitation

Wilmette gets around 4.1 in of rain over 12 wet days in May. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 39% and peaks near 41% on the wettest days.

0%10%20%30%40%50%151015202531
Rain chance (%)
140
240
341
441
541
641
741
840
940
1040
1139
1239
1339
1439
1539
1638
1738
1838
1938
2038
2138
2238
2338
2438
2539
2639
2739
2839
2940
3040
3140

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, May lands in the dry band about 77% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1936100
2926110
3907210
4907210
5898210
6888310
7879310
8869410
9859420
108310520
118310520
128210620
138210620
148110720
158110720
167811830
177811830
187711930
1975111040
2075111040
2172121150
2271121250
2370121260
2468131360
2567131370
2665141470
2764141480
2861151591
2960151591
30581615101
31571715101

Wind in May

Winds average 10 mph in May.

Across May, daily wind ranges from about 9 mph on the calmest days to 10 mph at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (mph)Feels
110light breeze
210light breeze
310light breeze
410light breeze
510light breeze
610light breeze
710light breeze
810light breeze
910light breeze
1010light breeze
1110light breeze
1210light breeze
1310light breeze
1410light breeze
1510light breeze
1610light breeze
1710light breeze
1810light breeze
1910light breeze
209light breeze
219light breeze
229light breeze
239light breeze
249light breeze
259light breeze
269light breeze
279light breeze
289light breeze
299light breeze
309light breeze
319light breeze

Sunrise & sunset in May

DaylightNight

Daylight runs from about 13 h 48 min at the start of May to 14 h 48 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 60 minutes over May. Sunrise moves from 4:54 AM to 4:24 AM, and sunset from 6:42 PM to 7:13 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.84:546:42
213.84:536:43
313.94:516:44
413.94:506:45
514.04:496:47
614.04:476:48
714.04:466:49
814.14:456:50
914.14:446:51
1014.24:426:52
1114.24:416:53
1214.24:406:54
1314.34:396:55
1414.34:386:56
1514.34:376:57
1614.44:366:58
1714.44:356:59
1814.44:347:00
1914.54:337:01
2014.54:327:02
2114.54:317:03
2214.64:307:04
2314.64:297:05
2414.64:297:06
2514.74:287:07
2614.74:277:08
2714.74:277:09
2814.74:267:10
2914.84:257:11
3014.84:257:12
3114.84:247:13

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.96 kWh/m².

For context, solar energy here swings from a low near 1.57 kWh/m² to a high of 6.57 kWh/m² in June across the year — May's 5.96 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
15.5Bright
25.6Bright
35.6Bright
45.6Bright
55.6Bright
65.7Bright
75.7Bright
85.7Bright
95.8Bright
105.8Bright
115.8Bright
125.8Bright
135.9Bright
145.9Bright
155.9Bright
166.0Bright
176.0Intense
186.0Intense
196.1Intense
206.1Intense
216.1Intense
226.1Intense
236.2Intense
246.2Intense
256.2Intense
266.2Intense
276.2Intense
286.2Intense
296.3Intense
306.3Intense
316.3Intense
Planning a trip in May

Is May a good time to visit Wilmette?

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

5.5
Sightseeing
5th-best month of the year
2.1
Beach & pool
5th-best month of the year

May is a reasonable time to visit Wilmette for sightseeing.

What to pack for Wilmette in May

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

In May, Wilmette sees daytime highs around 65°F and nights near 51°F. Worth packing: rain gear and sun protection. About 12 days see rain.

rain gearsun protection

Sea temperature near Wilmette in May

The nearest coast averages about 44°F in May — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea offshore is warmest in August at about 72°F and coldest in February near 36°F.

It's comfortable for a long swim from Jul 14 to Sep 14 — about 2.1 months when the water holds above 68°F.

30°40°50°60°70°80°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmcomfortable to swim
Sea temperature (°F)Comfort
Jan38Bracing
Feb36Bracing
Mar36Bracing
Apr39Bracing
May44Bracing
Jun56Bracing
Jul69Refreshing
Aug72Refreshing
Sep68Refreshing
Oct58Bracing
Nov48Bracing
Dec42Bracing

UV index in Wilmette in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 7 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Wilmette peaks around June 23 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 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 highHighModerateLowJun 23UV 9Dec 22UV 2
UV index (midday)Level
Jan2Low
Feb2Moderate
Mar4Moderate
Apr6High
May7Very high
Jun9Very high
Jul9Very high
Aug7Very high
Sep6High
Oct3Moderate
Nov2Moderate
Dec2Low

Air quality in Wilmette in May

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Wilmette is worst in July — around 21 µg/m³ PM2.5 (moderate), about 2.2× the cleanest month (October, 10 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodJul 921 µg/m³Oct 2410 µg/m³
PM2.5 (µg/m³)Level
Jan12Moderate
Feb15Moderate
Mar18Moderate
Apr19Moderate
May20Moderate
Jun21Moderate
Jul21Moderate
Aug18Moderate
Sep15Moderate
Oct10Good
Nov10Good
Dec11Good
Location & terrain

Where is Wilmette?

Wilmette sits at 42.1°N, 87.7°W, 636 ft above sea level, in United States. The nearest listed city is Evanston, 2.5 mi away.

Topography around Wilmette

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

Within 2 miles, the terrain around Wilmette has only modest variations in elevation — a maximum elevation change of 121 ft around an average of 627 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 177 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 784 ft.

The land around Wilmette is covered by trees (58%) and artificial surfaces (28%) within 2 miles, water (44%), artificial surfaces (29%) and trees (20%) within 10 miles, and water (43%) within 50 miles.

2 miles
121 ft
10 miles
177 ft
50 miles
784 ft
treesgrasslandcroplandartificial surfaceswater
May weather nearby: Evanston 2.5 mi · Skokie 2.5 mi · Glenview 3.1 mi · Morton Grove 3.7 mi · West Ridge 5.0 mi · Rogers Park 5.0 mi · Niles 5.6 mi · Northbrook 6.8 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 Wilmette (42.0722°, -87.7228°, elevation 636 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).