Dayton, OH Climate & Monthly Averages

Ohio, United States 🇺🇸 · humid subtropical climate
Annual avg
54°
Hottest month
July
Coldest month
January
Rainy days / yr
131
Sunshine
8.5 h/day
Right now: 77° and overcast - see live conditions

The climate of Dayton

Seasons are the whole story in Dayton. The gap between an average July and an average January is 25°C - hot, humid summers and generally mild winters - which in practice means 84°F (29°C) afternoons at one end of the calendar and 38°F (3°C) at the other.

Climate quick facts

  • Hottest month: July - highs near 84°F (29°C)
  • Coldest month: January - highs near 38°F (3°C)
  • Decade extremes (2015-2024): 95°F (35°C) high · -17°F (-27°C) low
  • Wettest month: May (14 rainy days) · Sunniest: July (11.8 h sun/day)
  • Climate type: humid subtropical
  • Annual swing: 25°C between the average warmest and coolest month · day to night: 10°C
  • Snow: about 12 days a year
  • Months with freezing average lows: 3
  • Average humidity: 71%

Temperatures through the year

Sunshine averages 8.5 hours a day over the year, peaking in July at 11.8 hours. January sits at the other end of the year: 38°F (3°C) by day, 24°F (-5°C) at night. July is the warm end of the year, averaging 84°F (29°C) by day and 67°F (20°C) overnight. The gridded 2015-2024 daily record for this location tops out at 95°F (35°C) and bottoms at -17°F (-27°C) - decade extremes, not all-time station records. May is the wettest month at 4.6 inches (117 mm) over 14 days; September is the driest.

Rain, sun and snow

Overnight lows average at or below freezing for 3 months, December through February.

How Dayton compares

  • Dayton sits close to the middle of our dataset on most measures: 54°F (12°C) as an annual average, 44.6 inches (1134 mm) of precipitation and 8.5 hours of sun a day.

Ranked against every city in our dataset, each measured on the same ten-year window.

Monthly climate table

Monthly averages for Dayton based on 2015–2024 weather data.
MonthHighLow Rain daysPrecipitation SunshineHumidity
January 38° 24° 10 3.5 in 5.2 h/day 72%
February 43° 26° 10 3.6 in 6.5 h/day 70%
March 52° 34° 12 4.6 in 7.4 h/day 67%
April 62° 43° 12 4.2 in 8.8 h/day 67%
May 73° 54° 14 4.6 in 10.1 h/day 71%
June 81° 63° 12 4.4 in 11.6 h/day 69%
July 84° 67° 13 4.2 in 11.8 h/day 73%
August 82° 65° 11 3.5 in 11.2 h/day 73%
September 78° 60° 8 2.9 in 9.9 h/day 70%
October 66° 49° 9 2.9 in 8.2 h/day 70%
November 52° 37° 8 2.9 in 6.4 h/day 71%
December 44° 30° 11 3.3 in 4.9 h/day 75%

Dayton month by month

Dayton weather in January

January brings highs around 38°F (3°C), lows near 24°F (-5°C), about 10 wet days and roughly 4 snowy days - typically the coldest month of the year in Dayton.

Dayton weather in February

February brings highs around 43°F (6°C), lows near 26°F (-4°C), about 10 wet days and roughly 3 snowy days.

Dayton weather in March

March brings highs around 52°F (11°C), lows near 34°F (1°C), about 12 wet days and roughly 2 snowy days.

Dayton weather in April

April brings highs around 62°F (17°C), lows near 43°F (6°C), about 12 wet days.

Dayton weather in May

May brings highs around 73°F (23°C), lows near 54°F (12°C), about 14 wet days - typically the wettest month of the year in Dayton.

Dayton weather in June

June brings highs around 81°F (27°C), lows near 63°F (17°C), about 12 wet days.

Dayton weather in July

July brings highs around 84°F (29°C), lows near 67°F (20°C), about 13 wet days - typically the hottest month and the sunniest month of the year in Dayton.

Dayton weather in August

August brings highs around 82°F (28°C), lows near 65°F (18°C), about 11 wet days.

Dayton weather in September

September brings highs around 78°F (26°C), lows near 60°F (16°C), about 8 wet days - typically the driest month of the year in Dayton.

Dayton weather in October

October brings highs around 66°F (19°C), lows near 49°F (10°C), about 9 wet days.

Dayton weather in November

November brings highs around 52°F (11°C), lows near 37°F (3°C), about 8 wet days.

Dayton weather in December

December brings highs around 44°F (7°C), lows near 30°F (-1°C), about 11 wet days and roughly 1 snowy days.

Seasons in Dayton

Spring (March through May)

Spring in Dayton is crisp but comfortable, with daytime highs averaging 62°F (17°C) and nights around 44°F (6°C); rain falls on around 38 of the 90 days, plus about 2 snowy days.

Summer (June through August)

Summer brings hot afternoons here - highs near 82°F (28°C), nights near 65°F (18°C), and rain falls on around 37 of the 90 days. Daylight is generous - around 11.5 hours of sun a day. With the moisture factored in, afternoons feel hotter than the reading suggests - the humidity and dew point converter shows why.

Fall (September through November)

Fall is crisp but comfortable here - highs near 66°F (19°C), nights near 49°F (9°C), and expect showers on roughly 25 days across the season.

Winter (December through February)

Winter in Dayton is chilly, with daytime highs averaging 42°F (5°C) and nights around 26°F (-3°C); rain falls on around 31 of the 90 days, plus about 8 snowy days.

Climate questions, answered

Is Dayton hot in summer?
July averages 84°F (29°C). Hot afternoons happen but extremes are not the norm.
Is Dayton humid?
Relative humidity averages 71% across the year, which reads as fairly humid. Paired with July heat, muggy afternoons are routine.
When does Dayton drop below freezing?
Average overnight lows sit at or below 0°C in 3 months of the year, December through February.
How cold does Dayton get in winter?
January nights average 24°F (-5°C). Frost and occasional ice are part of the season.
How much sun does Dayton get?
8.5 hours a day averaged over the year, peaking in July at 11.8 hours.
What should I wear in Dayton?
It depends on the month: July runs to 84°F (29°C) while January holds at 38°F (3°C). The full month-by-month breakdown is in the packing notes above.

Best time to visit Dayton

Aim for August to October and April if you get the choice: warm days, manageable rainfall and plenty of daylight line up, and highs average 72°F (22°C) against roughly 10 wet days a month. For the same question asked the other way round, see where else is warm in August.

Pack for Dayton with light clothing for the warm months, a heavy insulated coat, hat and gloves for winter and a compact umbrella or rain shell. Note the gap between afternoon and night: July pairs 84°F (29°C) with 67°F (20°C).

Dayton temperature records (2015-2024)

Highest recorded
95°
in August
Lowest recorded
-17°
in February
Annual precipitation
44.6"
Snowy days / yr
12

Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ.