Sumter weather in August: Sumter, South Carolina: normal highs, lows, rain and records for August
Sumter in August has a normal high of 89°F and a normal low of 68°F, a daily mean of 79°F, falling from 90°F on the 1st to 87°F by the 31st. Measurable precipitation falls on 11 days in a normal August, 4.92 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 31°C and low of 20°C, 125 mm of precipitation in August.
- NOAA stationSumter
- Station IDUSC00388440
- Location33.94°N 80.36°W
- Elevation177 ft (54 m)
- Population42,958
- Jan 55° 33°
- Feb 59° 35°
- Mar 66° 41°
- Apr 75° 50°
- May 81° 58°
- Jun 87° 66°
- Jul 90° 70°
- Aug 89° 68°
- Sep 83° 63°
- Oct 74° 51°
- Nov 65° 40°
- Dec 57° 35°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Sumter in August?
The normal high is 89°F and the normal low 68°F, for a daily mean of 78.5°F. August is 1.4°F cooler than July and 5.3°F warmer than September. August is the 2nd warmest month of the year in Sumter and the 3rd wettest. Across the month the normal high falls 3°F, from 90°F on August 1 to 87°F on August 31. From one year to the next August's mean temperature typically moves about 2.0°F either way (NOAA's standard deviation), so roughly two Augusts in three average between 77°F and 81°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 39%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| August 1 | 90°F | 70°F | 39% | 27% |
| August 8 | 89°F | 69°F | 38% | 27% |
| August 15 | 89°F | 69°F | 37% | 25% |
| August 22 | 88°F | 68°F | 34% | 23% |
| August 31 | 87°F | 67°F | 31% | 20% |
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 | 90°F | 70°F | 39% | 27% | 13 h 50 min |
| August 2 | 90°F | 69°F | 39% | 27% | 13 h 50 min |
| August 3 | 90°F | 69°F | 39% | 27% | 13 h 50 min |
| August 4 | 90°F | 69°F | 39% | 27% | 13 h 50 min |
| August 5 | 90°F | 69°F | 39% | 27% | 13 h 40 min |
| August 6 | 89°F | 69°F | 39% | 27% | 13 h 40 min |
| August 7 | 89°F | 69°F | 39% | 27% | 13 h 40 min |
| August 8 | 89°F | 69°F | 38% | 27% | 13 h 40 min |
| August 9 | 89°F | 69°F | 38% | 26% | 13 h 40 min |
| August 10 | 89°F | 69°F | 38% | 26% | 13 h 40 min |
| August 11 | 89°F | 69°F | 38% | 26% | 13 h 30 min |
| August 12 | 89°F | 69°F | 37% | 26% | 13 h 30 min |
| August 13 | 89°F | 69°F | 37% | 26% | 13 h 30 min |
| August 14 | 89°F | 69°F | 37% | 25% | 13 h 30 min |
| August 15 | 89°F | 69°F | 37% | 25% | 13 h 30 min |
| August 16 | 89°F | 69°F | 36% | 25% | 13 h 30 min |
| August 17 | 89°F | 69°F | 36% | 24% | 13 h 20 min |
| August 18 | 88°F | 68°F | 36% | 24% | 13 h 20 min |
| August 19 | 88°F | 68°F | 35% | 24% | 13 h 20 min |
| August 20 | 88°F | 68°F | 35% | 23% | 13 h 20 min |
| August 21 | 88°F | 68°F | 34% | 23% | 13 h 20 min |
| August 22 | 88°F | 68°F | 34% | 23% | 13 h 10 min |
| August 23 | 88°F | 68°F | 34% | 22% | 13 h 10 min |
| August 24 | 88°F | 68°F | 33% | 22% | 13 h 10 min |
| August 25 | 88°F | 68°F | 33% | 22% | 13 h 10 min |
| August 26 | 88°F | 68°F | 32% | 21% | 13 h 10 min |
| August 27 | 87°F | 67°F | 32% | 21% | 13 h |
| August 28 | 87°F | 67°F | 32% | 21% | 13 h |
| August 29 | 87°F | 67°F | 32% | 21% | 13 h |
| August 30 | 87°F | 67°F | 31% | 20% | 13 h |
| August 31 | 87°F | 67°F | 31% | 20% | 13 h |
- Normal high
- 89°FAugust average
- Normal low
- 68°FAugust average
- Precipitation
- 4.92 inmonth total
- Days with precipitation
- 110.01 inch or more
- Days at 90°F or more
- 14
- Daylight
- 13 h 50 min to 13 hAugust 1 to August 31
- Days at 70°F or more
- 31
- Days at 80°F or more
- 30
- Sunshine
- 80%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USC00388440; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Sumter in August?
On a given August day the chance of 0.01 inch or more is 36% on average, highest around August 1 (39%). In all, 4.92 in falls on 11 days of a normal August, 1 of them with an inch or more.
In a normal August in Sumter, 14 days reach 90°F.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USC00388440.
What are the records for August in Sumter?
The warmest August temperature on this station's record (since 1901) is 105°F, on August 1, 1980; the coldest is 50°F, on August 18, 1979. The wettest August brought 14.29 in (1952).
The August mean against the 1991-2020 normal of 78.5°F: 2021 79.5°F (+1.0), 2022 80.3°F (+1.8), 2023 82.3°F (+3.8), 2024 80.0°F (+1.5), 2025 77.9°F (−0.6). 4 of 5 ran warmer than normal.
| August | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 79.5°F | +1.0°F | 2.18 in |
| 2022 | 80.3°F | +1.8°F | 4.45 in |
| 2023 | 82.3°F | +3.8°F | 6.85 in |
| 2024 | 80.0°F | +1.5°F | 8.88 in |
| 2025 | 77.9°F | −0.6°F | – |
Source: records: ACIS, station USC00388440; recent months: ACIS, station USC00388440. Records and recent months use complete months only.
How does August in Sumter compare across South Carolina?
Across the 73 places PlainClimate covers in South Carolina, August normal highs run from 76°F in Caesars Head to 92°F in Pelion; Sumter's is 89°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.