Mason weather in January

In January, Mason sees average daytime highs of 39°F and overnight lows near 25°F, with 3.4 in of precipitation across 10.4 wet days and about 9.5 hours of daylight. It is the 12th-warmest and 7th-wettest month of the year here.

Day-to-day highs hold fairly steady near 39°F through the month. The sky is clear or mostly clear about 20% of the time in January, and the air most often feels dry.

Daylight stretches from about 9 h 18 min at the start of January to 9 h 54 min by month's end. Set against the rest of the year, January is Mason's 12th-clearest and 2nd-windiest month. For the whole year in context, see Mason's year-round climate.

Daytime high
39°
12th warmest
Overnight low
25°
1st coldest
Precipitation
3.4 in
10.4 wet days
Daylight
9 h 30 min
8:01 AM – 5:32 PM
Cloud cover
72%
12th clearest
Wind
8 mph
2nd windiest
Solar energy
2 kWh/m²
Travel score
0.0
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 January

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 39°F through the month.

A typical January day in Mason reaches about 39°F in the afternoon and slips back to 25°F overnight — a 14°F spread between the day's warmth and the night's chill. On most days the high lands between 23°F and 55°F. Set against its neighbours, January runs about 4°F cooler than December and about 4°F cooler than February.

20°40°60°151015202531
Avg high (°F)Avg low (°F)
14027
24027
34027
44027
54027
64026
74026
83926
93926
103926
113925
123925
133825
143825
153824
163824
173824
183824
193824
203824
213823
223823
233823
243823
253823
263824
273824
283824
293924
303924
313924

How January really feels in Mason

Once humidity and wind are folded in, January averages 0 days that feel above 90°F and 31 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
31
wind chill below the day's low

The story in January is cold — wind chill drags the overnight "feels like" below the raw low.

Mason weather by month

How January compares with the rest of the year at a glance. January is the 12th-warmest and 7th-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 January

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 20% of the time in January, the cloudiest month of the year.

Beyond those clear spells, partly cloudy skies cover about 10% of January, with mostly cloudy or overcast conditions the remaining 70%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13169
23169
33169
43070
52872
62872
72872
82872
92872
102872
112872
122971
132971
142971
153070
163070
173070
183070
193070
203268
213268
223268
233268
243268
253268
263268
273268
283268
293268
303268
313268

Chance of precipitation in January

Any precipitationSnow

Mason gets around 3.4 in of rain and snow over 10.4 wet days in January. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 34% and peaks near 36% on the wettest days, and about 4 days bring snow.

0%10%20%30%40%50%151015202531
Rain chance (%)Snow chance (%)
13412
23412
33512
43513
53613
63613
73613
83614
93614
103614
113615
123615
133615
143616
153616
163616
173516
183516
193416
203416
213316
223315
233215
243215
253115
263115
273115
283114
293114
303014
313014

Humidity in January

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, January lands in the dry band about 99% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)
1982
2982
3982
4982
5982
6982
7982
8982
9982
10982
11982
12991
13991
14991
15991
16991
17991
18991
191000
201000
211000
221000
231000
241000
251000
261000
271000
281000
291000
301000
311000

Wind in January

Winds average 8 mph in January.

Across January, daily wind ranges from about 8 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
228light breeze
238light breeze
248light breeze
258light breeze
268light breeze
278light breeze
288light breeze
298light breeze
308light breeze
318light breeze

Sunrise & sunset in January

DaylightNight

Daylight runs from about 9 h 18 min at the start of January to 9 h 54 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 36 minutes over January. Sunrise moves from 8:02 AM to 7:53 AM, and sunset from 5:19 PM to 5:48 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.38:025:19
29.38:025:19
39.38:035:20
49.38:035:21
59.38:035:22
69.38:035:22
79.38:035:23
89.48:035:24
99.48:035:25
109.48:025:26
119.48:025:27
129.48:025:28
139.48:025:29
149.58:025:30
159.58:015:31
169.58:015:32
179.58:015:33
189.68:005:34
199.68:005:35
209.68:005:36
219.67:595:37
229.77:595:38
239.77:585:39
249.77:585:40
259.77:575:42
269.87:565:43
279.87:565:44
289.87:555:45
299.97:545:46
309.97:545:47
319.97:535:48

Solar energy in January

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in January, about 2 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 — January's 2 kWh/m² sits near the bottom.

0123151015202531
Solar energy (kWh/m²)Level
11.7Dim
21.7Dim
31.7Dim
41.7Dim
51.8Dim
61.8Dim
71.8Dim
81.8Dim
91.8Dim
101.8Dim
111.9Dim
121.9Dim
131.9Dim
141.9Dim
151.9Dim
162.0Dim
172.0Moderate
182.0Moderate
192.1Moderate
202.1Moderate
212.1Moderate
222.1Moderate
232.2Moderate
242.2Moderate
252.3Moderate
262.3Moderate
272.3Moderate
282.3Moderate
292.4Moderate
302.4Moderate
312.4Moderate
Planning a trip in January

Is January a good time to visit Mason?

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

0.0
Sightseeing
12th-best month of the year
0.0
Beach & pool
10th-best month of the year

January is a weaker month for outdoor sightseeing in Mason.

What to pack for Mason in January

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

In January, Mason sees daytime highs around 39°F and nights near 25°F. Pack a warm layer and a heavy coat. Worth having: rain gear. About 10 days see rain.

a warm layera heavy coatrain gear

UV index in Mason in January

LowModerateHighVery highExtreme

Clear-sky midday UV in January peaks around 2. 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 January

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where January 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
January 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).