Indianapolis, IN climate: monthly averages and frost dates
Indianapolis, IN has cold winters and warm summers by this site's scale, with wet annual precipitation. The figures are the 1991–2020 climate normals for NOAA station USW00093819 (INDIANAPOLIS), 9 mi (14 km) in a straight line from the city's center point (US Census).
- Warmest month high
- 85.2°F
- July
- Coldest month mean
- 28.5°F
- January
- Precipitation
- 43.6 in
- per year
- Snowfall
- 25.5 in
- per year
- Median last frost
- April 15
- 32°F, spring
- Median first frost
- October 26
- 32°F, autumn
Monthly averages in Indianapolis
| Month | High °F | Low °F | Mean °F | Precip. in | Snow in | Days ≥0.01 in | Days ≥90°F | Nights ≤32°F |
|---|---|---|---|---|---|---|---|---|
| January | 36.1 | 20.9 | 28.5 | 3.12 | 8.8 | 12.3 | 0.0 | 25.7 |
| February | 40.8 | 24.2 | 32.5 | 2.43 | 6.0 | 10.3 | 0.0 | 22.3 |
| March | 51.9 | 33.0 | 42.4 | 3.69 | 3.2 | 11.5 | 0.0 | 15.8 |
| April | 63.9 | 43.3 | 53.6 | 4.34 | 0.2 | 11.9 | 0.0 | 3.7 |
| May | 73.4 | 53.7 | 63.6 | 4.75 | 0.0 | 13.3 | 0.3 | 0.2 |
| June | 82.0 | 62.9 | 72.5 | 4.95 | 0.0 | 11.5 | 3.4 | 0.0 |
| July | 85.2 | 66.4 | 75.8 | 4.42 | 0.0 | 10.3 | 7.4 | 0.0 |
| August | 84.3 | 65.0 | 74.7 | 3.20 | 0.0 | 8.3 | 5.9 | 0.0 |
| September | 78.2 | 57.4 | 67.8 | 3.14 | 0.0 | 7.9 | 2.8 | 0.0 |
| October | 65.6 | 45.5 | 55.5 | 3.22 | 0.1 | 8.9 | 0.1 | 2.1 |
| November | 51.8 | 34.9 | 43.3 | 3.45 | 0.8 | 10.2 | 0.0 | 13.0 |
| December | 40.4 | 26.2 | 33.3 | 2.92 | 6.4 | 11.8 | 0.0 | 22.6 |
| Year | 62.8 | 44.5 | 53.6 | 43.63 | 25.5 | 128.2 | 19.9 | 105.5 |
How cold is winter in Indianapolis?
Winters in Indianapolis are cold by this site's scale (coldest-month mean 20 to under 32°F). The coldest month is January, with a mean temperature of 28.5°F (−1.9°C), a normal daily high of 36.1°F (2.3°C) and a normal daily low of 20.9°F (−6.2°C).
The station averages 105.5 nights a year at or below 32°F and 29.1 days when the high stays at or below 32°F.
The normal daily low is at or below freezing in December to February.
How hot is summer in Indianapolis?
Summers in Indianapolis are warm by this site's scale (hottest-month high 80 to under 90°F). July has the highest normal daily high, 85.2°F (29.6°C), with nights averaging 66.4°F (19.1°C).
The high reaches 90°F or more on 19.9 days in a normal year.
What is the wettest month in Indianapolis?
Indianapolis gets 43.63 in (1108 mm) of precipitation in a normal year, which this site classes as wet (40 to under 60 in a year). The wettest month is June with 4.95 in (126 mm); the driest is February with 2.43 in (62 mm).
Measurable precipitation (0.01 in or more) falls on 128.2 days a year.
Does it snow in Indianapolis?
Normal annual snowfall in Indianapolis is 25.5 in (65 cm), which this site classes as moderate (12 to under 36 in a year).
January is the snowiest month, with 8.8 in (22 cm).
A day with 1.0 in or more of snowfall comes 7.6 times a year on average.
Which months are mild in Indianapolis?
5 months in Indianapolis meet this site's comfort thresholds (normal high 65–85°F, low 45°F or higher, fewer than 10 days with 0.10 in or more of precipitation): May, June and August to October.
July misses by one threshold only (normal high 85.2°F, above the 85°F limit).
Thresholds and their limits: methodology.
Frost dates and growing season in Indianapolis
In Indianapolis the median last spring night at or below 32°F is April 15, and the median first autumn one is October 26 (NOAA P50 dates). NOAA's median length of the freeze-free season is 193 days. NOAA takes that median over each year's own season, so it need not equal the 194 days between the two median dates.
There is still a 10% chance of a 32°F night on or after May 2, and a 10% chance that the first one has come by October 13.
The chance that the last spring 32°F night comes on or after April 2 is 90%.
For a hard freeze (28°F or lower) the median dates are April 4 in spring and November 5 in autumn.
| Chance | Last spring 32°F night on or after | First autumn 32°F night by | Freeze-free season, days |
|---|---|---|---|
| 10% | May 2 | October 13 | 212 |
| 20% | April 26 | October 18 | 205 |
| 30% | April 21 | October 21 | 201 |
| 40% | April 18 | October 24 | 197 |
| 50% | April 15 | October 26 | 193 |
| 60% | April 12 | October 28 | 189 |
| 70% | April 9 | October 30 | 184 |
| 80% | April 6 | November 2 | 178 |
| 90% | April 2 | November 7 | 171 |
| Threshold | Median last date (spring) | Median first date (autumn or winter) | Median season, days |
|---|---|---|---|
| 36°F | April 26 | October 17 | 171 |
| 32°F | April 15 | October 26 | 193 |
| 28°F | April 4 | November 5 | 215 |
| 24°F | March 24 | November 17 | 239 |
| 20°F | March 13 | November 28 | 260 |
| 16°F | March 3 | December 6 | 281 |
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 100% | 100% | 100% | 91% | 12% | 0% | 0% | 0% | 1% | 73% | 100% | 100% |
Nearby and similar places
Of the places on this site, the closest to Indianapolis by station distance are Chicago, IL at 180 mi (290 km), Detroit, MI at 233 mi (374 km) and Nashville, TN at 249 mi (401 km).
Among places whose winter, summer and precipitation words are each within one band of Indianapolis's (winter: cold, summer: warm, precipitation: wet), the closest monthly temperature and precipitation patterns are Washington, DC, Chicago, IL and Philadelphia, PA.
Compared with Chicago, IL, Indianapolis's peak-month normal high is 0.7°F (0.4°C) higher, its coldest-month mean is 3.3°F (1.8°C) higher, and its annual precipitation is 5.77 in more.
| Place | Listed as | Station distance | Coldest mean °F | Warmest high °F | Precip. in/yr | Snow in/yr | Last frost |
|---|---|---|---|---|---|---|---|
| Indianapolis, IN | this page | – | 28.5 | 85.2 | 43.6 | 25.5 | April 15 |
| Chicago, IL | nearby, similar | 180 mi (290 km) | 25.2 | 84.5 | 37.9 | 38.4 | April 16 |
| Detroit, MI | nearby | 233 mi (374 km) | 25.8 | 83.7 | 34.3 | 45.0 | April 20 |
| Nashville, TN | nearby | 249 mi (401 km) | 39.6 | 90.9 | 50.5 | 4.7 | March 31 |
| Washington, DC | similar | 498 mi (801 km) | 37.5 | 89.6 | 41.8 | 13.7 | March 24 |
| Philadelphia, PA | similar | 586 mi (944 km) | 33.7 | 87.8 | 44.1 | 23.1 | April 2 |
How nearby and similar places are chosen: methodology.
Source and station
The data for Indianapolis come from NOAA station INDIANAPOLIS, IN US (USW00093819) at 39.7075, -86.2803, elevation 790 ft (241 m). It lies 9 mi (14 km) in a straight line from the center point of Indianapolis city (balance), the “internal point” in the US Census 2024 Gazetteer.
Each monthly normal used here rests on at least 28 years of data from 1991–2020 (NOAA's per-field year counts).
NOAA completeness flags on the monthly fields used here:
- S: Standard: meets WMO standards for data availability for 24 or more years.
Cite the data as:
Palecki, Michael; Durre, Imke; Applequist, Scott; Arguez, Anthony; Lawrimore, Jay (2021). U.S. Climate Normals 2020: U.S. Monthly Climate Normals (1991-2020). Station USW00093819 (INDIANAPOLIS, IN US). NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.25921/wck8-er13. Accessed 2026-10-09.
Palecki, Michael; Durre, Imke; Applequist, Scott; Arguez, Anthony; Lawrimore, Jay (2021). U.S. Climate Normals 2020: U.S. Annual/Seasonal Climate Normals (1991-2020). Station USW00093819 (INDIANAPOLIS, IN US). NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.25921/4ek7-fk11. Accessed 2026-10-09.
Files used: monthly normals CSV, annual/seasonal normals CSV (retrieved 2026-10-09). The values on this page as JSON: /us/in/indianapolis/data.json.