Quincy weather in August: Quincy, Illinois: normal highs, lows, rain and records for August
Quincy in August has a normal high of 85°F and a normal low of 65°F, a daily mean of 75°F, falling from 86°F on the 1st to 83°F by the 31st. Measurable precipitation falls on 8 days in a normal August, 3.93 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 29°C and low of 18°C, 100 mm of precipitation in August.
- NOAA stationQuincy Regional Airport
- Station IDUSW00093989
- Location39.94°N 91.19°W
- Elevation769 ft (234 m)
- From the center10 miles
- Population38,786
- Jan 35° 19°
- Feb 40° 23°
- Mar 52° 32°
- Apr 64° 43°
- May 73° 54°
- Jun 82° 63°
- Jul 86° 67°
- Aug 85° 65°
- Sep 78° 56°
- Oct 65° 45°
- Nov 51° 33°
- Dec 39° 24°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Quincy in August?
The normal high is 85°F and the normal low 65°F, for a daily mean of 74.5°F. August is 1.8°F cooler than July and 7.5°F warmer than September. August is the 2nd warmest month of the year in Quincy and the 4th wettest. Across the month the normal high falls 3°F, from 86°F on August 1 to 83°F on August 31. From one year to the next August's mean temperature typically moves about 2.6°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 28%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| August 1 | 86°F | 66°F | 28% | 18% |
| August 8 | 85°F | 66°F | 28% | 17% |
| August 15 | 85°F | 65°F | 27% | 17% |
| August 22 | 84°F | 64°F | 27% | 17% |
| August 31 | 83°F | 62°F | 26% | 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 | 86°F | 66°F | 28% | 18% | 14 h 20 min |
| August 2 | 86°F | 66°F | 28% | 18% | 14 h 20 min |
| August 3 | 86°F | 66°F | 28% | 18% | 14 h 10 min |
| August 4 | 86°F | 66°F | 28% | 18% | 14 h 10 min |
| August 5 | 86°F | 66°F | 28% | 18% | 14 h 10 min |
| August 6 | 86°F | 66°F | 28% | 17% | 14 h 10 min |
| August 7 | 85°F | 66°F | 28% | 17% | 14 h 10 min |
| August 8 | 85°F | 66°F | 28% | 17% | 14 h |
| August 9 | 85°F | 66°F | 28% | 17% | 14 h |
| August 10 | 85°F | 66°F | 28% | 17% | 14 h |
| August 11 | 85°F | 66°F | 28% | 17% | 14 h |
| August 12 | 85°F | 65°F | 28% | 17% | 13 h 50 min |
| August 13 | 85°F | 65°F | 27% | 17% | 13 h 50 min |
| August 14 | 85°F | 65°F | 27% | 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 | 65°F | 27% | 17% | 13 h 40 min |
| August 19 | 84°F | 64°F | 27% | 17% | 13 h 40 min |
| August 20 | 84°F | 64°F | 27% | 17% | 13 h 40 min |
| August 21 | 84°F | 64°F | 27% | 17% | 13 h 30 min |
| August 22 | 84°F | 64°F | 27% | 17% | 13 h 30 min |
| August 23 | 84°F | 64°F | 26% | 17% | 13 h 30 min |
| August 24 | 84°F | 63°F | 26% | 17% | 13 h 30 min |
| August 25 | 84°F | 63°F | 26% | 16% | 13 h 20 min |
| August 26 | 83°F | 63°F | 26% | 16% | 13 h 20 min |
| August 27 | 83°F | 63°F | 26% | 16% | 13 h 20 min |
| August 28 | 83°F | 62°F | 26% | 16% | 13 h 20 min |
| August 29 | 83°F | 62°F | 26% | 16% | 13 h 10 min |
| August 30 | 83°F | 62°F | 26% | 16% | 13 h 10 min |
| August 31 | 83°F | 62°F | 26% | 16% | 13 h 10 min |
- Normal high
- 85°FAugust average
- Normal low
- 65°FAugust average
- Precipitation
- 3.93 inmonth total
- Days with precipitation
- 80.01 inch or more
- Days at 90°F or more
- 7
- 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
- 25
- Sunshine
- 81%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00093989; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Quincy in August?
On a given August day the chance of 0.01 inch or more is 27% on average, highest around August 1 (28%). In all, 3.93 in falls on 8 days of a normal August, 1 of them with an inch or more.
In a normal August in Quincy, 7 days reach 90°F.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00093989.
What are the records for August in Quincy?
The warmest August temperature on Quincy's official record (since 1901) is 111°F, on August 9, 1934; the coldest is 42°F, on August 20, 1950. The wettest August brought 10.84 in (1970).
The August mean against the 1991-2020 normal of 74.5°F: 2021 76.2°F (+1.7), 2022 75.8°F (+1.3), 2023 75.0°F (+0.5), 2024 75.3°F (+0.8), 2025 73.4°F (−1.1), 2026 75.2°F (+0.7). 5 of 6 ran warmer than normal.
| August | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 76.2°F | +1.7°F | 0.94 in |
| 2022 | 75.8°F | +1.3°F | 0.72 in |
| 2023 | 75.0°F | +0.5°F | 3.62 in |
| 2024 | 75.3°F | +0.8°F | 2.01 in |
| 2025 | 73.4°F | −1.1°F | 1.19 in |
| 2026 | 75.2°F | +0.7°F | 2.97 in |
Source: records: ACIS, NWS threaded record UINthr; recent months: ACIS, station USW00093989. Records and recent months use complete months only.
How does August in Quincy compare across Illinois?
Across the 144 places PlainClimate covers in Illinois, August normal highs run from 79°F in Barrington to 89°F in Anna; Quincy's is 85°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.