Mason weather in May

In May, Mason sees average daytime highs of 73°F and overnight lows near 56°F, with 4.7 in of rain across 13.1 wet days and about 14.1 hours of daylight. It is the 5th-warmest and 1st-wettest month of the year here.

Highs climb over the month, from about 70°F in the first days to 77°F by the end. The sky is clear or mostly clear about 24% of the time in May, and the air most often feels dry.

Daylight stretches from about 13 h 36 min at the start of May to 14 h 30 min by month's end. Set against the rest of the year, May is Mason's 8th-clearest and 7th-windiest month. For the whole year in context, see Mason's year-round climate.

Daytime high
73°
5th warmest
Overnight low
56°
8th coldest
Rainfall
4.7 in
13.1 wet days
Daylight
14 h 12 min
5:29 AM – 7:38 PM
Cloud cover
64%
8th clearest
Wind
7 mph
7th windiest
Solar energy
5.69 kWh/m²
Travel score
6.2
out of 10

Mason is city in Warren County, Ohio, United States.

Density
676/km²
people per km²
Founded
1815

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 70°F in the first days to 77°F by the end.

A typical May day in Mason reaches about 73°F in the afternoon and slips back to 56°F overnight — a 18°F spread between the day's warmth and the night's chill. On most days the high lands between 62°F and 84°F. Set against its neighbours, May runs about 9°F warmer than April and about 8°F cooler than June.

40°60°80°151015202531
Avg high (°F)Avg low (°F)
16951
26951
36952
47052
57052
67153
77153
87153
97154
107254
117254
127255
137355
147355
157355
167356
177356
187456
197456
207457
217557
227558
237558
247658
257658
267659
277759
287760
297760
307860
317860

How May really feels in Mason

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.

Mason 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
Jan39° / 25°3.410.44.39.50.0
Feb42° / 27°3.09.43.810.50.4
Mar52° / 35°4.211.4211.72.7
Apr65° / 46°4.712.70.5135.3
May73° / 56°4.713.1014.16.2
Jun82° / 65°4.212.2014.75.8
Jul85° / 68°3.511.2014.55.3
Aug83° / 66°2.99.5013.55.9
Sep78° / 59°2.78012.37.2
Oct65° / 47°3.08.50.1116.1
Nov53° / 37°3.49.30.89.83.0
Dec43° / 30°3.810.42.99.30.4

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 24% 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 61%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13862
23862
33862
43763
53763
63763
73862
83862
93862
103763
113763
123763
133862
143763
153763
163763
173763
183763
193763
203862
213961
223961
234060
244060
254258
264258
274357
284258
294357
304456
314456

Chance of precipitation in May

Any precipitation

Mason gets around 4.7 in of rain over 13.1 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 42% and peaks near 45% on the wettest days.

0%20%40%60%151015202531
Rain chance (%)
144
244
344
445
545
645
745
845
945
1045
1145
1245
1344
1444
1544
1643
1743
1842
1941
2041
2140
2240
2340
2439
2539
2639
2739
2839
2939
3039
3139

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 56% 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 (%)
17815700
27615810
37416910
473161010
570171120
669171220
767171330
867171330
965171440
1063171550
1163171550
1261171660
1360171670
1458171780
1558171780
1656171890
17551718100
18531719110
19531719110
20511720120
21491720130
22481721141
23461821141
24451822151
25441922151
26421922161
27411922161
28411922171
29401923181
30391923181
31381923191

Wind in May

Winds average 7 mph in May.

Across May, daily wind ranges from about 6 mph on the calmest days to 8 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (mph)Feels
18light breeze
27light breeze
37calm
47calm
57calm
67calm
77calm
87calm
97calm
107calm
117calm
127calm
137calm
147calm
157calm
167calm
177calm
187calm
197calm
207calm
217calm
227calm
237calm
247calm
257calm
267calm
276calm
286calm
296calm
306calm
316calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 13 h 36 min at the start of May to 14 h 30 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 5:45 AM to 5:18 AM, and sunset from 7:23 PM to 7:51 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.65:457:23
213.75:447:24
313.75:437:25
413.75:427:26
513.85:417:27
613.85:397:28
713.95:387:29
813.95:377:30
913.95:367:31
1014.05:357:32
1114.05:347:33
1214.05:337:34
1314.15:327:35
1414.15:317:36
1514.15:307:37
1614.25:297:38
1714.25:287:39
1814.25:277:40
1914.25:267:41
2014.35:257:42
2114.35:257:43
2214.35:247:43
2314.45:237:44
2414.45:227:45
2514.45:227:46
2614.45:217:47
2714.55:217:48
2814.55:207:49
2914.55:197:49
3014.55:197:50
3114.55:187:51

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.69 kWh/m².

For context, solar energy here swings from a low near 1.68 kWh/m² to a high of 6.18 kWh/m² in June across the year — May's 5.69 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
65.4Bright
75.4Bright
85.5Bright
95.5Bright
105.5Bright
115.5Bright
125.6Bright
135.6Bright
145.6Bright
155.6Bright
165.7Bright
175.7Bright
185.7Bright
195.8Bright
205.8Bright
215.8Bright
225.8Bright
235.9Bright
245.9Bright
255.9Bright
266.0Bright
276.0Bright
286.0Bright
296.0Bright
306.0Intense
316.0Intense
Planning a trip in May

Is May a good time to visit Mason?

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

6.2
Sightseeing
2nd-best month of the year
4.8
Beach & pool
5th-best month of the year

May is a reasonable time to visit Mason for sightseeing.

What to pack for Mason in May

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

In May, Mason sees daytime highs around 73°F and nights near 56°F. Worth packing: light clothes, rain gear and sun protection. About 13 days see rain.

light clothesrain gearsun protection

UV index in Mason in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 8 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Mason peaks around June 21 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.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highHighModerateJun 21UV 9Dec 22UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar5Moderate
Apr6High
May8Very high
Jun9Very high
Jul9Very high
Aug8Very high
Sep6High
Oct3Moderate
Nov3Moderate
Dec2Low

Air quality in Mason 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 Mason is worst in July — around 19 µg/m³ PM2.5 (moderate), about 2.2× the cleanest month (October, 8 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1418 µg/m³Oct 248 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb11Good
Mar11Good
Apr12Good
May15Moderate
Jun18Moderate
Jul19Moderate
Aug16Moderate
Sep13Moderate
Oct8Good
Nov9Good
Dec9Good
Location & terrain

Where is Mason?

Mason sits at 39.4°N, 84.3°W, 810 ft above sea level, in United States. The nearest listed city is Lebanon, 7.5 mi away.

Topography around Mason

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

Within 2 miles, the terrain around Mason has only modest variations in elevation — a maximum elevation change of 240 ft around an average of 817 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 492 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 912 ft.

The land around Mason is covered by grassland (39%), trees (36%) and artificial surfaces (22%) within 2 miles, trees (43%) and grassland (29%) within 10 miles, and trees (42%) and cropland (36%) within 50 miles.

2 miles
240 ft
10 miles
492 ft
50 miles
912 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
May weather nearby: Lebanon 7.5 mi · Forest Park 11 mi · Middletown 12 mi · Fairfield 14 mi · Hamilton 14 mi · Springboro 14 mi · Norwood 16 mi · White Oak 19 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 Mason (39.3601°, -84.3099°, elevation 810 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. 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).