Dayton weather in May: Dayton, Ohio: normal highs, lows, rain and records for May
Dayton in May has a normal high of 74°F and a normal low of 54°F, a daily mean of 64°F, rising from 70°F on the 1st to 78°F by the 31st. Measurable precipitation falls on 14 days in a normal May, 4.51 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 23°C and low of 12°C, 115 mm of precipitation in May.
- NOAA stationDayton International Airport
- Station IDUSW00093815
- Location39.91°N 84.22°W
- Elevation1,000 ft (305 m)
- From the center8 miles
- Population136,346
- 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.
How warm is Dayton in May?
The normal high is 74°F and the normal low 54°F, for a daily mean of 64.0°F. May is 10.3°F warmer than April and 8.7°F cooler than June. May is the 5th warmest month of the year in Dayton and the wettest. Across the month the normal high rises 8°F, from 70°F on May 1 to 78°F on May 31. From one year to the next May's mean temperature typically moves about 3.6°F either way (NOAA's standard deviation), so roughly two Mays in three average between 60°F and 68°F.
Bars above: each day's normal high to low. Columns below: the chance of 0.01 inch or more of precipitation that day, on a scale of 0 to 100% (highest 45%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| May 1 | 70°F | 49°F | 45% | 30% |
| May 8 | 72°F | 51°F | 45% | 30% |
| May 15 | 74°F | 54°F | 45% | 29% |
| May 22 | 76°F | 56°F | 44% | 28% |
| May 31 | 78°F | 59°F | 43% | 27% |
Every day of May: normal high, low and chance of precipitation (warmest afternoon May 31, coldest night May 1)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| May 1 | 70°F | 49°F | 45% | 30% | 13 h 50 min |
| May 2 | 70°F | 49°F | 45% | 30% | 13 h 50 min |
| May 3 | 71°F | 50°F | 45% | 30% | 14 h |
| May 4 | 71°F | 50°F | 45% | 30% | 14 h |
| May 5 | 71°F | 50°F | 45% | 30% | 14 h |
| May 6 | 72°F | 51°F | 45% | 30% | 14 h |
| May 7 | 72°F | 51°F | 45% | 30% | 14 h |
| May 8 | 72°F | 51°F | 45% | 30% | 14 h 10 min |
| May 9 | 72°F | 52°F | 45% | 30% | 14 h 10 min |
| May 10 | 73°F | 52°F | 45% | 30% | 14 h 10 min |
| May 11 | 73°F | 52°F | 45% | 30% | 14 h 10 min |
| May 12 | 73°F | 53°F | 45% | 30% | 14 h 20 min |
| May 13 | 73°F | 53°F | 45% | 29% | 14 h 20 min |
| May 14 | 74°F | 53°F | 45% | 29% | 14 h 20 min |
| May 15 | 74°F | 54°F | 45% | 29% | 14 h 20 min |
| May 16 | 74°F | 54°F | 45% | 29% | 14 h 20 min |
| May 17 | 74°F | 54°F | 45% | 29% | 14 h 20 min |
| May 18 | 75°F | 55°F | 45% | 29% | 14 h 30 min |
| May 19 | 75°F | 55°F | 44% | 29% | 14 h 30 min |
| May 20 | 75°F | 55°F | 44% | 28% | 14 h 30 min |
| May 21 | 76°F | 56°F | 44% | 28% | 14 h 30 min |
| May 22 | 76°F | 56°F | 44% | 28% | 14 h 30 min |
| May 23 | 76°F | 56°F | 44% | 28% | 14 h 30 min |
| May 24 | 76°F | 56°F | 44% | 28% | 14 h 40 min |
| May 25 | 77°F | 57°F | 44% | 28% | 14 h 40 min |
| May 26 | 77°F | 57°F | 44% | 28% | 14 h 40 min |
| May 27 | 77°F | 57°F | 44% | 27% | 14 h 40 min |
| May 28 | 78°F | 58°F | 44% | 27% | 14 h 40 min |
| May 29 | 78°F | 58°F | 43% | 27% | 14 h 40 min |
| May 30 | 78°F | 58°F | 43% | 27% | 14 h 50 min |
| May 31 | 78°F | 59°F | 43% | 27% | 14 h 50 min |
- Normal high
- 74°FMay average
- Normal low
- 54°FMay average
- Precipitation
- 4.51 inmonth total
- Days with precipitation
- 140.01 inch or more
- Daylight
- 13 h 50 min to 14 h 50 minMay 1 to May 31
- Days at 70°F or more
- 20
- Days at 80°F or more
- 9
- Sunshine
- 72%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00093815; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Dayton in May?
On a given May day the chance of 0.01 inch or more is 44% on average, highest around May 9 (45%). In all, 4.51 in falls on 14 days of a normal May, 1 of them with an inch or more.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00093815.
How humid and windy is Dayton in May?
At 3 p.m. the normal temperature is 75°F with 51% relative humidity and a dew point of 56°F; at 6 a.m. it is 60°F with 83% humidity. The wind averages 8.8 mph, most often from the west-southwest in the afternoon.
| Time | Temperature | Dew point | Humidity | Wind | Clear or few clouds |
|---|---|---|---|---|---|
| 6 a.m. | 60°F | 55°F | 83% | 7.1 mph | 37% |
| 9 a.m. | 67°F | 56°F | 68% | 9.3 mph | – |
| noon | 73°F | 56°F | 56% | 10.7 mph | – |
| 3 p.m. | 75°F | 56°F | 51% | 11.3 mph | – |
| 6 p.m. | 73°F | 56°F | 54% | 10.3 mph | 26% |
| 9 p.m. | 67°F | 56°F | 68% | 7.4 mph | 38% |
Source: NOAA NCEI 1991-2020 hourly normals, station USW00093815. Hourly normals exist only for NOAA's first-order stations; a dash where NOAA publishes no value for that hour (the sky at some hours).
What are the records for May in Dayton?
The warmest May temperature on Dayton's official record (since 1893) is 98°F, on May 29, 1911; the coldest is 26°F, on May 1, 1963. The wettest May brought 10.31 in (2026).
The May mean against the 1991-2020 normal of 64.0°F: 2021 60.9°F (−3.1), 2022 66.4°F (+2.4), 2023 62.6°F (−1.4), 2024 68.3°F (+4.3), 2025 61.6°F (−2.4), 2026 60.0°F (−4.0). 2 of 6 ran warmer than normal.
| May | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 60.9°F | −3.1°F | 4.26 in |
| 2022 | 66.4°F | +2.4°F | 5.36 in |
| 2023 | 62.6°F | −1.4°F | 1.89 in |
| 2024 | 68.3°F | +4.3°F | 3.93 in |
| 2025 | 61.6°F | −2.4°F | 5.00 in |
| 2026 | 60.0°F | −4.0°F | 10.31 in |
Source: records: ACIS, NWS threaded record DAYthr; recent months: ACIS, station USW00093815. Records and recent months use complete months only.
How does May in Dayton compare across Ohio?
Across the 99 places PlainClimate covers in Ohio, May normal highs run from 69°F in Sandusky to 76°F in Milford; Dayton's is 74°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.