Dayton weather in August: Dayton, Ohio: normal highs, lows, rain and records for August
Dayton in August has a normal high of 85°F and a normal low of 64°F, a daily mean of 75°F, falling from 85°F on the 1st to 83°F by the 31st. Measurable precipitation falls on 8 days in a normal August, 2.96 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 29°C and low of 18°C, 75 mm of precipitation in August.
- 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 August?
The normal high is 85°F and the normal low 64°F, for a daily mean of 74.5°F. August is 1.5°F cooler than July and 6.8°F warmer than September. August is the 2nd warmest month of the year in Dayton and the 10th wettest. Across the month the normal high falls 2°F, from 85°F on August 1 to 83°F on August 31. From one year to the next August's mean temperature typically moves about 2.3°F either way (NOAA's standard deviation), so roughly two Augusts in three average between 72°F and 77°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 30%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| August 1 | 85°F | 66°F | 30% | 20% |
| August 8 | 85°F | 65°F | 29% | 18% |
| August 15 | 85°F | 65°F | 27% | 17% |
| August 22 | 84°F | 64°F | 26% | 16% |
| August 31 | 83°F | 62°F | 27% | 16% |
Every day of August: normal high, low and chance of precipitation (warmest afternoon August 1, coldest night August 31)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| August 1 | 85°F | 66°F | 30% | 20% | 14 h 20 min |
| August 2 | 85°F | 66°F | 30% | 20% | 14 h 20 min |
| August 3 | 85°F | 66°F | 30% | 20% | 14 h 10 min |
| August 4 | 85°F | 66°F | 30% | 19% | 14 h 10 min |
| August 5 | 85°F | 66°F | 29% | 19% | 14 h 10 min |
| August 6 | 85°F | 66°F | 29% | 19% | 14 h 10 min |
| August 7 | 85°F | 65°F | 29% | 19% | 14 h 10 min |
| August 8 | 85°F | 65°F | 29% | 18% | 14 h |
| August 9 | 85°F | 65°F | 29% | 18% | 14 h |
| August 10 | 85°F | 65°F | 28% | 18% | 14 h |
| August 11 | 85°F | 65°F | 28% | 18% | 14 h |
| August 12 | 85°F | 65°F | 28% | 18% | 13 h 50 min |
| August 13 | 85°F | 65°F | 28% | 17% | 13 h 50 min |
| August 14 | 85°F | 65°F | 28% | 17% | 13 h 50 min |
| August 15 | 85°F | 65°F | 27% | 17% | 13 h 50 min |
| August 16 | 85°F | 65°F | 27% | 17% | 13 h 50 min |
| August 17 | 85°F | 65°F | 27% | 17% | 13 h 40 min |
| August 18 | 85°F | 64°F | 27% | 17% | 13 h 40 min |
| August 19 | 85°F | 64°F | 27% | 16% | 13 h 40 min |
| August 20 | 85°F | 64°F | 27% | 16% | 13 h 40 min |
| August 21 | 84°F | 64°F | 26% | 16% | 13 h 30 min |
| August 22 | 84°F | 64°F | 26% | 16% | 13 h 30 min |
| August 23 | 84°F | 64°F | 26% | 16% | 13 h 30 min |
| August 24 | 84°F | 63°F | 26% | 16% | 13 h 30 min |
| August 25 | 84°F | 63°F | 26% | 16% | 13 h 20 min |
| August 26 | 84°F | 63°F | 26% | 16% | 13 h 20 min |
| August 27 | 84°F | 63°F | 26% | 16% | 13 h 20 min |
| August 28 | 84°F | 63°F | 26% | 16% | 13 h 20 min |
| August 29 | 84°F | 62°F | 27% | 16% | 13 h 10 min |
| August 30 | 83°F | 62°F | 27% | 16% | 13 h 10 min |
| August 31 | 83°F | 62°F | 27% | 16% | 13 h 10 min |
- Normal high
- 85°FAugust average
- Normal low
- 64°FAugust average
- Precipitation
- 2.96 inmonth total
- Days with precipitation
- 80.01 inch or more
- Days at 90°F or more
- 4
- Daylight
- 14 h 20 min to 13 h 10 minAugust 1 to August 31
- Days at 70°F or more
- 31
- Days at 80°F or more
- 23
- Sunshine
- 81%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 August?
On a given August day the chance of 0.01 inch or more is 28% on average, highest around August 1 (30%). In all, 2.96 in falls on 8 days of a normal August, 1 of them with an inch or more.
In a normal August in Dayton, 4 days reach 90°F.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00093815.
How humid and windy is Dayton in August?
At 3 p.m. the normal temperature is 81°F with 50% relative humidity and a dew point of 60°F; at 6 a.m. it is 63°F with 88% humidity. The wind averages 7.2 mph, most often from the west in the afternoon.
| Time | Temperature | Dew point | Humidity | Wind | Clear or few clouds |
|---|---|---|---|---|---|
| 6 a.m. | 63°F | 60°F | 88% | 5.6 mph | 56% |
| 9 a.m. | 71°F | 62°F | 74% | 7.5 mph | 50% |
| noon | 78°F | 62°F | 57% | 8.8 mph | 33% |
| 3 p.m. | 81°F | 60°F | 50% | 9.5 mph | 32% |
| 6 p.m. | 78°F | 61°F | 56% | 8.7 mph | 46% |
| 9 p.m. | 71°F | 61°F | 72% | 6.3 mph | 61% |
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 August in Dayton?
The warmest August temperature on Dayton's official record (since 1893) is 103°F, on August 5, 1918; the coldest is 40°F, on August 28, 1910. The wettest August brought 8.73 in (2026).
The August mean against the 1991-2020 normal of 74.5°F: 2021 76.9°F (+2.4), 2022 74.7°F (+0.2), 2023 73.1°F (−1.4), 2024 74.8°F (+0.3), 2025 71.3°F (−3.2), 2026 73.3°F (−1.2). 3 of 6 ran warmer than normal.
| August | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 76.9°F | +2.4°F | 2.91 in |
| 2022 | 74.7°F | +0.2°F | 1.59 in |
| 2023 | 73.1°F | −1.4°F | 4.47 in |
| 2024 | 74.8°F | +0.3°F | 2.91 in |
| 2025 | 71.3°F | −3.2°F | 1.34 in |
| 2026 | 73.3°F | −1.2°F | 8.73 in |
Source: records: ACIS, NWS threaded record DAYthr; recent months: ACIS, station USW00093815. Records and recent months use complete months only.
How does August in Dayton compare across Ohio?
Across the 99 places PlainClimate covers in Ohio, August normal highs run from 79°F in Ashtabula to 87°F in Lucasville; Dayton's is 85°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.