Indianapolis, IN weather in August
Expect warm, often humid weather with some rain in Indianapolis in August, with highs near 84°F and lows near 65°F. Rain falls on about 8 days. It is one of the warmest months in Indianapolis.
- Normal high
- 84°F
- Normal low
- 65°F
- Wet days
- 8
- 3.2 in total
- Muggy days
- 14
- dew point 65°F+
How August changes from start to finish
| August 1 | August 31 | |
|---|---|---|
| Normal high | 85°F | 83°F |
| Normal low | 66°F | 63°F |
| Chance of a wet day | 29% | 26% |
| Sunrise / sunset | 6:43 am / 8:58 pm | 7:11 am / 8:18 pm |
| Daylight | 14.2 h | 13.1 h |
Chance of a wet day: average for the first and last 7 days of the month. Times are local clock time (Eastern Time).
A typical August day
- 6 am66°Fdew point 63°F
- 9 am73°Fdew point 64°F
- Noon80°Fdew point 64°F
- 3 pm82°Fdew point 63°F
- 6 pm80°Fdew point 63°F
- 9 pm74°Fdew point 64°F
NOAA hourly normals (local standard time) from Indianapolis (9 mi away); average wind 7 mph.
What kind of days to expect
- Comfortable dayshigh 65-80°F and dew point under 60°F4 of 31
- Hot dayshigh 90°F or more6 of 31
- Muggy daysdaily mean dew point 65°F or more14 of 31
- Wet daysat least 0.01 in of rain or melted snow8 of 31
- Notable rainat least 0.10 in6 of 31
- Freezing nightslow 32°F or below0 of 31
- Snow on the groundsnow depth 1 in or more0 of 31
Average days per August, counted from daily records for each year 1991-2020.
Rain in August
Normal precipitation is 3.2 in; a dry August brings about 1.8 in and a wet one about 4.2 in (25th and 75th percentiles). About 2 days bring half an inch or more, and about 1 an inch or more.
How August varies from year to year
- Warmest August, 1991-20202010: average high 90°F
- Coolest August2004: average high 79°F
- Wettest August2016: 7.3 in
- Driest August2010: 0.4 in
- Highest reading98°F (August 8, 2012)
- Lowest reading47°F (August 12, 2004)
From the station's daily records with NOAA quality flags removed; most recent date shown when a reading repeats.
August compared with July and September
| July | August | September | |
|---|---|---|---|
| Normal high | 85°F | 84°F | 78°F |
| Normal low | 66°F | 65°F | 57°F |
| Wet days | 10 | 8 | 8 |
| Comfortable days | 3 | 4 | 13 |
| Daylight | 14.7 h | 13.7 h | 12.4 h |
Highs change by -1°F from July and -6°F into September.
Nearby alternatives in August
- Warmer: Bowling Green, KY193 mi · high 89°F · 9 wet days
How Indianapolis ranks in August
- Normal high221st warmest of 378 cities; 2nd of 6 in Indiana
- Wet days166th driest of 378
- Comfortable days145th most of 341
What to pack for Indianapolis in August
- A rain jacket or umbrella – rain on about 8 days
Heating and cooling
August has 2 heating degree days and 301 cooling degree days (base 65°F), 5% of the year's total heating and cooling demand.
Questions
How hot is Indianapolis in August?
The normal high is 84°F and the normal low is 65°F. From 1991 to 2020 the hottest August reading was 98°F (most recently on August 8, 2012).
Does it rain a lot in Indianapolis in August?
About 8 days in August have at least 0.01 in of precipitation, and the normal total is 3.2 in. The wettest August in 1991-2020 was in 2016 (7.3 in); the driest was in 2010 (0.4 in).
Is August a good time to visit Indianapolis?
August ranks 6th of 12 months on our comfort score for Indianapolis (54 out of 100). It has about 4 comfortable days and about 6 days at 90°F or hotter. The best months are April and May.
Where the numbers come from
- Temperature, rain, snowfall, snow depth, frost dates and humidity and wind by hour: Indianapolis (USW00093819), 8.6 mi SW of the city center, 790 ft (72 ft higher than the city). NOAA normals and daily records, 1991-2020.
- Daily humidity and wind: Indianapolis International Airport (724380-93819), 8.1 mi WSW of the city center, 792 ft (74 ft higher than the city). Hourly observations, 1991-2020.
- Not available for this location: cloud cover (no station close enough or similar enough in elevation).