Dayton, Ohio climate: Normal weather by month, frost dates and records
Dayton's normal year runs from 22°F January nights to 86°F July afternoons, with 41.3 inches of precipitation and 25 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 12.2°C, January lows of −6°C, July highs of 30°C, 1,050 mm of precipitation a year.
- NOAA stationDayton International Airport
- Station IDUSW00093815
- Location39.91°N 84.22°W
- Elevation1,000 ft (305 m)
- From the center8 miles
- Population136,346
On October 22, the normal high in Dayton is 64°F and the normal low 44°F, and the chance of measurable rain or snow is 31%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Dayton.
- Jan 37° 22°
- Feb 41° 25°
- Mar 52° 33°
- Apr 65° 43°
- May 74° 54°
- Jun 83° 63°
- Jul 86° 66°
- Aug 85° 64°
- Sep 79° 57°
- Oct 66° 46°
- Nov 53° 35°
- Dec 42° 27°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in Dayton each month?
July is the warmest month, with normal highs of 86°F; January the coldest, with normal lows of 22°F. The most precipitation falls in May (4.51 in), the least in February (2.35 in).
Each month has its own page with the day-by-day normals, the month's records and its recent years:
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 37°F | 22°F | 29.4°F | 3.08 | 8.3 | 13 | <1 | 26 | 9 h 40 min |
| February | 41°F | 25°F | 32.8°F | 2.35 | 6.6 | 11 | <1 | 23 | 10 h 40 min |
| March | 52°F | 33°F | 42.1°F | 3.50 | 3.9 | 12 | <1 | 17 | 11 h 50 min |
| April | 65°F | 43°F | 53.7°F | 4.46 | 0.4 | 13 | <1 | 5 | 13 h 10 min |
| May | 74°F | 54°F | 64.0°F | 4.51 | 0.0 | 14 | <1 | <1 | 14 h 20 min |
| June | 83°F | 63°F | 72.7°F | 4.14 | 0.0 | 12 | 3 | <1 | 15 h |
| July | 86°F | 66°F | 76.0°F | 3.95 | 0.0 | 11 | 6 | <1 | 14 h 40 min |
| August | 85°F | 64°F | 74.5°F | 2.96 | 0.0 | 8 | 4 | <1 | 13 h 50 min |
| September | 79°F | 57°F | 67.7°F | 3.31 | 0.0 | 9 | 2 | <1 | 12 h 30 min |
| October | 66°F | 46°F | 56.0°F | 2.95 | 0.2 | 10 | <1 | 2 | 11 h 10 min |
| November | 53°F | 35°F | 44.1°F | 3.07 | 0.8 | 10 | <1 | 14 | 10 h |
| December | 42°F | 27°F | 34.3°F | 3.05 | 4.8 | 12 | <1 | 23 | 9 h 20 min |
| Year (annual) | 63°F | 45°F | 53.9°F | 41.33 | 25.0 | 134 | 16 | 110 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 3°C | −6°C | −1.4°C | 78 mm | 21 cm |
| February | 5°C | −4°C | 0.4°C | 60 mm | 17 cm |
| March | 11°C | 0°C | 5.6°C | 89 mm | 10 cm |
| April | 18°C | 6°C | 12.1°C | 113 mm | 1 cm |
| May | 23°C | 12°C | 17.8°C | 115 mm | 0 cm |
| June | 28°C | 17°C | 22.6°C | 105 mm | 0 cm |
| July | 30°C | 19°C | 24.4°C | 100 mm | 0 cm |
| August | 29°C | 18°C | 23.6°C | 75 mm | 0 cm |
| September | 26°C | 14°C | 19.8°C | 84 mm | 0 cm |
| October | 19°C | 8°C | 13.3°C | 75 mm | 1 cm |
| November | 12°C | 2°C | 6.7°C | 78 mm | 2 cm |
| December | 5°C | −3°C | 1.3°C | 77 mm | 12 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00093815; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
When is the best weather to visit Dayton?
Normal highs sit between 65°F and 85°F in May, June, August, September and October. Of those, August has the fewest days with rain (8).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USW00093815.
When is the last frost in Dayton?
In Dayton, the last spring frost (32°F) comes after April 16 in half of years and after May 3 in one year in ten; the first autumn frost comes before October 28 in half of years and before October 16 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- April 161 year in 10 after May 3; 9 in 10 after April 2
- First autumn frost, half of years before
- October 281 year in 10 before October 16; 9 in 10 before November 9
NOAA puts the median frost-free season at 194 days, and the season without a hard freeze (28°F) at 215 days.
A hard freeze (28°F) comes after April 4 in half of springs and before November 6 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Dayton in zone 6b across its 15 ZIP code areas (6b in 45417, the largest). By the map's own method, the average of each year's coldest night over 1991-2020, Dayton's NOAA station is in zone 6b: the coldest night of a typical year reaches −5°F (30 complete years).
Frost dates for every NOAA station in Ohio · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USW00093815; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
What hardiness zone is each Dayton ZIP code in?
The USDA's 2023 map gives each ZIP code area one zone. Dayton's 15 ZIP code areas are all in zone 6b. Each ZIP's frost dates are in the frost tool.
| ZIP code | Zone | Land in Dayton |
|---|---|---|
| 45377 | 6b | 13.2 km² |
| 45402 | 6b | 11.3 km² |
| 45403 | 6b | 8.2 km² |
| 45404 | 6b | 14.5 km² |
| 45405 | 6b | 6.2 km² |
| 45406 | 6b | 10.8 km² |
| 45409 | 6b | 2.9 km² |
| 45410 | 6b | 6.2 km² |
| 45414 | 6b | 12.5 km² |
| 45417 | 6b | 31.4 km² |
| 45419 | 6b | 1.3 km² |
| 45420 | 6b | 6.1 km² |
| 45424 | 6b | 10.5 km² |
| 45428 | 6b | 1.2 km² |
| 45432 | 6b | 2.1 km² |
Source: USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; ZIP areas in the place: Census Bureau 2020 ZCTA-to-place relationship file. A ZIP area counts when at least a tenth of its land (and 0.5 km²) lies in the place.
How hot and how cold does it get in Dayton?
In a normal year in Dayton, 16 days a year reach 90°F, 110 nights fall to 32°F or colder and 134 days bring measurable precipitation.
- Days at 90°F or more
- 16a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 110a normal year
- Days that stay below freezing
- 33high of 32°F or less
- Days with 0.01 inch of precipitation
- 134a normal year
- Days with 1 inch of snow or more
- 8a normal year
The highest temperature in Dayton's official record (kept by the National Weather Service since 1893) is 108°F, on July 22, 1901; the lowest is −28°F, on February 13, 1899.
The wettest calendar year on that record is 1990, with 59.75 in; the snowiest season is 1977–78, with 62.7 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USW00093815; records: ACIS (NOAA Regional Climate Centers), NWS threaded record DAYthr. Records use complete months only; a month missing more than three days is left out.
How humid and windy is Dayton, and how clear are its skies?
The summer (June-August) dew point averages 62°F. The muggiest month is July, with an average dew point of 63°F; the driest air comes in January (21°F). February is the windiest month (11.2 mph on average), and September has the most clear or nearly clear hours (52%).
| Month | Dew point | Humidity | Afternoon humidity | Wind | Clear or few clouds | Overcast |
|---|---|---|---|---|---|---|
| January | 21°F | 74% | 64% | 10.8 mph | 30% | 51% |
| February | 26°F | 70% | 58% | 11.2 mph | 30% | 50% |
| March | 35°F | 63% | 49% | 10.9 mph | 35% | 42% |
| April | 44°F | 63% | 49% | 10.3 mph | 37% | 34% |
| May | 56°F | 67% | 51% | 8.8 mph | 38% | 26% |
| June | 62°F | 68% | 52% | 7.9 mph | 47% | 18% |
| July | 63°F | 70% | 52% | 7.0 mph | 46% | 16% |
| August | 61°F | 70% | 50% | 7.2 mph | 51% | 17% |
| September | 50°F | 68% | 48% | 8.6 mph | 52% | 23% |
| October | 39°F | 69% | 54% | 9.9 mph | 40% | 39% |
| November | 30°F | 74% | 63% | 10.9 mph | 27% | 53% |
| December | 24°F | 77% | 69% | 11.0 mph | 24% | 58% |
Source: NOAA NCEI 1991-2020 hourly normals, station USW00093815. Monthly averages of all hours; afternoon humidity at 3 p.m. local standard time; sky as the share of hours NOAA's observations rate clear or few clouds (a dash where NOAA publishes no sky value).
How sunny is Dayton?
Over a year 72% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Dayton, 4.0 kWh per square metre a day. August is the sunniest month (81%) and December the cloudiest (58%). Among the 459 U.S. places of 50,000 or more, that ranks tied 385th (with 30 others) in sunshine.
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 59% | 1.8 |
| February | 62% | 2.6 |
| March | 65% | 3.6 |
| April | 71% | 4.9 |
| May | 72% | 5.5 |
| June | 78% | 6.2 |
| July | 79% | 6.0 |
| August | 81% | 5.5 |
| September | 79% | 4.6 |
| October | 72% | 3.2 |
| November | 69% | 2.2 |
| December | 58% | 1.5 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How much heating and cooling does Dayton need?
A normal year in Dayton brings 5,149 heating degree days, 4% fewer than the median U.S. place (5,373), and 1,154 cooling degree days, 27% more than the median (908). Seven months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 3,757 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,102 | 0 |
| February | 900 | 0 |
| March | 712 | 2 |
| April | 354 | 15 |
| May | 125 | 94 |
| June | 13 | 242 |
| July | 1 | 341 |
| August | 3 | 296 |
| September | 58 | 139 |
| October | 300 | 23 |
| November | 629 | 1 |
| December | 952 | 0 |
| Year (annual) | 5,149 | 1,154 |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00093815. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
Has Dayton been warmer than normal lately?
2025 averaged 53.5°F, 0.4°F below the 1991-2020 normal of 53.9°F. 3 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2021 | 55.0°F | +1.1°F | 41.31 | 24.7 |
| 2022 | 53.9°F | at normal | 37.34 | 21.2 |
| 2023 | 55.6°F | +1.8°F | 35.18 | 12.7 |
| 2024 | 56.9°F | +3.0°F | 41.04 | 16.5 |
| 2025 | 53.5°F | −0.4°F | 40.75 | 32.7 |
Over 74 complete years from 1951 to 2025, the station's annual mean temperature rose at a fitted 3.2°F per century (+0.18°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USW00093815; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Dayton's climate compare?
Dayton is warmer than 90 of the other 98 places with their own NOAA record in Ohio, and wetter than 45. Across the 7,247 U.S. stations with normals, its annual mean of 53.9°F is warmer than 57%.
In the Köppen classification computed from these normals, Dayton is Dfa: continental, no dry season, hot summer. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Which places near Dayton share this climate record?
18 places have no NOAA station with 1991-2020 normals of their own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- Huber Heights, OH43,590 people · 6 mi SE
- Riverside, OH24,472 people · 10 mi SE
- Trotwood, OH23,073 people · 10 mi SW
- Vandalia, OH15,013 people · 2 mi SE
- Clayton, OH13,296 people · 6 mi SW
- Englewood, OH13,282 people · 6 mi SW
- Shiloh, OH10,785 people · 6 mi S
- Tipp City, OH10,596 people · 4 mi NE
- Oakwood, OH9,400 people · 13 mi S
- Union, OH7,076 people · 4 mi W
- Brookville, OH5,946 people · 11 mi SW
- West Milton, OH4,855 people · 7 mi NW
- Fort McKinley, OH3,832 people · 7 mi S
- Drexel, OH1,659 people · 12 mi S
- Phillipsburg, OH498 people · 10 mi W
- Laura, OH413 people · 12 mi NW
- Potsdam, OH231 people · 11 mi W
- Ludlow Falls, OH178 people · 9 mi NW
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
What do Dayton's other NOAA stations record?
2 more NOAA stations keep 1991-2020 normals in or near Dayton. This page uses Dayton International Airport; the others differ by site and elevation:
| Station | From the center | Elevation | Year | Jan low | Jul high | Precip. | Snow | Last frost |
|---|---|---|---|---|---|---|---|---|
| Dayton Mcd USC00332067 | 2 mi S | 720 ft | 53.3°F | 20°F | 87°F | 41.6 | 12 | April 18 |
| Dayton Wright Bros Airport USW00053859 | 13 mi S | 962 ft | 54.1°F | 22°F | 86°F | 41.0 | – | April 17 |
Source: NOAA NCEI 1991-2020 normals for each station. Last frost: the median last spring date of 32°F.
Questions about Dayton's climate
What is the coldest month in Dayton?
January, with a normal high of 37°F and a normal low of 22°F. The warmest is July (86°F by day, 66°F at night).
Does it snow in Dayton?
Yes: 25 inches in a normal year, falling on 25 days with 0.1 inch or more, the most in January (8.3 inches).
What is the rainiest month in Dayton?
May, with 4.51 in of precipitation in a normal year; the driest is February with 2.35 in.
What plant hardiness zone is Dayton in?
The USDA's 2023 map puts Dayton in zone 6b across its 15 ZIP code areas (6b in 45417, the largest). By the same method at Dayton's NOAA station, the coldest night of a typical year reaches −5°F (30 years, 1991-2020): zone 6b.
How late can frost come in Dayton?
In half of years the last 32°F night comes after April 16; in one year in ten it comes after May 3. Waiting until May 3 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Dayton in OctoberThis month day by day, its records and recent years
- Ohio climateThe statewide normals and every place in the state
- New Carlisle, OH10 miles from this station, 51.9°F a year
- Piqua, OH16 miles from this station, 52.7°F a year
- Springfield, OH22 miles from this station, 51.2°F a year
- Franklin, OH25 miles from this station, 52.7°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made