Quincy weather in May

In May, Quincy sees average daytime highs of 74°F and overnight lows near 55°F, with 4.6 in of rain across 12.7 wet days and about 14.2 hours of daylight. It is the 5th-warmest and 1st-wettest month of the year here.

Highs climb over the month, from about 69°F in the first days to 78°F by the end. The sky is clear or mostly clear about 27% of the time in May, and the air most often feels dry.

Daylight stretches from about 13 h 42 min at the start of May to 14 h 36 min by month's end. Set against the rest of the year, May is Quincy's 7th-clearest and 8th-windiest month. For the whole year in context, see Quincy's year-round climate.

Daytime high
74°
5th warmest
Overnight low
55°
8th coldest
Rainfall
4.6 in
12.7 wet days
Daylight
14 h 12 min
4:56 AM – 7:08 PM
Cloud cover
62%
7th clearest
Wind
8 mph
8th windiest
Solar energy
5.76 kWh/m²
Travel score
6.3
out of 10

Quincy is county seat of Adams County, Illinois, United States.

Density
988/km²
people per km²
Founded
1819

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 69°F in the first days to 78°F by the end.

A typical May day in Quincy reaches about 74°F in the afternoon and slips back to 55°F overnight — a 18°F spread between the day's warmth and the night's chill. On most days the high lands between 61°F and 85°F. Set against its neighbours, May runs about 10°F warmer than April and about 9°F cooler than June.

40°60°80°151015202531
Avg high (°F)Avg low (°F)
16950
26950
36951
47051
57052
67052
77153
87153
97153
107253
117254
127354
137355
147355
157355
167455
177456
187456
197456
207557
217557
227558
237658
247658
257659
267759
277759
287860
297860
307860
317861

How May really feels in Quincy

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.

Quincy weather by month

How May compares with the rest of the year at a glance. May is the 5th-warmest and 1st-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan36° / 20°1.97.24.29.50.0
Feb40° / 24°2.273.210.40.2
Mar52° / 34°2.99.61.811.72.8
Apr64° / 45°4.411.30.3135.4
May74° / 55°4.612.7014.26.3
Jun83° / 65°4.010.5014.85.8
Jul86° / 69°3.49014.55.2
Aug84° / 66°3.28.4013.65.7
Sep78° / 58°3.37.4012.37.3
Oct65° / 46°2.88.50.210.96.2
Nov51° / 35°2.97.60.99.82.8
Dec40° / 25°2.16.92.89.20.2

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 27% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 17% of May, with mostly cloudy or overcast conditions the remaining 56%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13862
23862
33961
43961
54060
64159
74159
84159
94357
104357
114357
124456
134555
144555
154555
164555
174555
184654
194654
204654
214555
224654
234654
244654
254654
264654
274555
284555
294654
304654
314753

Chance of precipitation in May

Any precipitation

Quincy gets around 4.6 in of rain over 12.7 wet days in May, the wettest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 41% and peaks near 44% on the wettest days.

0%10%20%30%40%50%151015202531
Rain chance (%)
144
244
344
444
544
643
743
843
943
1042
1142
1242
1341
1441
1541
1641
1741
1841
1940
2040
2140
2240
2340
2440
2539
2639
2739
2839
2938
3038
3137

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 57% of days. Sticky, muggy-or-worse air turns up on roughly 9% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
17913710
27614820
37415920
472161020
570161130
668171230
766181330
864181440
963181540
1061181650
1161181650
1260181750
1358181860
1459171860
1557171970
1657171970
1757161980
1855162090
19541520101
20531521101
21521521111
22501522121
23491422131
24481423141
25461523151
26451523161
27441523171
28421623181
29411623191
30391723201
31381723211

Wind in May

Winds average 8 mph in May.

Across May, daily wind ranges from about 7 mph on the calmest days to 8 mph at its breeziest. It stays fairly steady from day to day.

051015151015202531
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
198light breeze
208light breeze
218light breeze
227light breeze
237light breeze
247calm
257calm
267calm
277calm
287calm
297calm
307calm
317calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 13 h 42 min at the start of May to 14 h 36 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 54 minutes over May. Sunrise moves from 5:13 AM to 4:45 AM, and sunset from 6:53 PM to 7:21 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.75:136:53
213.75:126:54
313.75:106:55
413.85:096:56
513.85:086:57
613.95:076:58
713.95:056:59
813.95:047:00
914.05:037:01
1014.05:027:02
1114.05:017:03
1214.15:007:04
1314.14:597:05
1414.14:587:06
1514.24:577:07
1614.24:567:08
1714.24:557:09
1814.34:547:10
1914.34:537:11
2014.34:527:12
2114.34:527:12
2214.44:517:13
2314.44:507:14
2414.44:497:15
2514.54:497:16
2614.54:487:17
2714.54:477:18
2814.54:477:19
2914.64:467:19
3014.64:467:20
3114.64:457:21

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.76 kWh/m².

For context, solar energy here swings from a low near 1.84 kWh/m² to a high of 6.44 kWh/m² in June across the year — May's 5.76 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
15.3Bright
25.3Bright
35.4Bright
45.4Bright
55.4Bright
65.5Bright
75.5Bright
85.6Bright
95.6Bright
105.6Bright
115.7Bright
125.7Bright
135.7Bright
145.8Bright
155.8Bright
165.8Bright
175.8Bright
185.9Bright
195.9Bright
205.9Bright
215.9Bright
225.9Bright
235.9Bright
245.9Bright
256.0Bright
266.0Bright
276.0Bright
286.0Bright
296.0Intense
306.0Intense
316.0Intense
Planning a trip in May

Hazard calendar for Quincy

In seasonPeak

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

Quincy sits in the Atlantic hurricane belt; the season peaks August–October.

Atlantic hurricane
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is May a good time to visit Quincy?

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

6.3
Sightseeing
2nd-best month of the year
4.9
Beach & pool
5th-best month of the year

May is a reasonable time to visit Quincy for sightseeing.

What to pack for Quincy in May

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

In May, Quincy sees daytime highs around 74°F and nights near 55°F. Worth packing: light clothes, rain gear and sun protection. About 13 days see rain.

light clothesrain gearsun protection

UV index in Quincy in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 8 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Quincy peaks around June 20 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 9 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highHighModerateJun 20UV 9Dec 22UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar5Moderate
Apr6High
May8Very high
Jun10Very high
Jul9Very high
Aug8Very high
Sep7High
Oct4Moderate
Nov3Moderate
Dec2Low

Air quality in Quincy 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 Quincy is worst in July — around 16 µg/m³ PM2.5 (moderate), about 2.3× the cleanest month (October, 7 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodGoodModerateGoodJul 1716 µg/m³Oct 237 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb12Moderate
Mar12Good
Apr10Good
May13Moderate
Jun14Moderate
Jul16Moderate
Aug14Moderate
Sep11Good
Oct7Good
Nov7Good
Dec8Good
Location & terrain

Where is Quincy?

Quincy sits at 39.9°N, 91.4°W, 568 ft above sea level, in United States. The nearest listed city is Hannibal, 16 mi away.

Topography around Quincy

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

Within 2 miles, the terrain around Quincy has only modest variations in elevation — a maximum elevation change of 230 ft around an average of 551 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 328 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 702 ft.

The land around Quincy is covered by trees (35%) and artificial surfaces (29%) within 2 miles, cropland (53%) and trees (26%) within 10 miles, and cropland (53%) and trees (32%) within 50 miles.

2 miles
230 ft
10 miles
328 ft
50 miles
702 ft
treesgrasslandcroplandartificial surfaceswater
May weather nearby: Hannibal 16 mi · Macomb 53 mi · Burlington 62 mi · Jacksonville 64 mi · Kirksville 65 mi · Wentzville 83 mi · Columbia 84 mi · O'Fallon 86 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 Quincy (39.9356°, -91.4099°, elevation 568 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. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). 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).