Indianapolis climate

Name: Indianapolis
Address: US

Indianapolis is warmest in July, with average highs of 29 °C, and coldest in January, when nights average -5.3 °C. May is the wettest month (124 mm) and February the driest (69 mm). Figures are 1991–2020 climate normals.

Across a full year Indianapolis averages 1,085 mm of rain, 109 days above 25 °C and 92 days below freezing.

United States · 218 m elevation · population 887,642 · 1991–2020 normals

Temperature below 0 °C to above 30 °C Rain band height is that month’s share of the wettest month

Warmest month July 29 °C
Coldest month January -5.3 °C
Driest month February 69 mm
Wettest month May 124 mm
Least cloud September 46 % cloud
Hottest on record June 39 °C
Coldest on record January -33 °C

What to expectIndianapolis through the year

Indianapolis has a clear annual cycle: average daily highs run from 2.6 °C in January to 29 °C in July, a swing of 26 °C in mean temperature across the year.

Counted across a normal year, 109 days a year reach 25 °C, 32 of them reach 30 °C, 92 nights drop below freezing. The warmest reading in the 1991–2020 record is 39 °C, in June.

Rain is spread fairly evenly through the year, from 69 mm in February to 124 mm in May. There is no dry season to aim for.

Month by month

Month	Avg high	Rainfall	Cloud
January	2.6 °C	79 mm	70 %
February	5.2 °C	69 mm	69 %
March	10.8 °C	97 mm	64 %
April	17.5 °C	122 mm	62 %
May	22.7 °C	124 mm	61 %
June	27.2 °C	107 mm	56 %
July	29.0 °C	94 mm	51 %
August	28.4 °C	72 mm	49 %
September	25.1 °C	74 mm	46 %
October	18.3 °C	82 mm	53 %
November	10.8 °C	87 mm	62 %
December	4.8 °C	78 mm	70 %

Temperature month by month

Month	Avg high	Avg low	Mean	Record high	Record low	Days above 25 °C	Days above 30 °C	Days below 0 °C
January	2.6 °C	-5.3 °C	-1.9 °C	18.5 °C	-33.5 °C	0	0	25
February	5.2 °C	-3.7 °C	-0.0 °C	23.3 °C	-25.7 °C	0	0	21
March	10.8 °C	1.0 °C	5.3 °C	27.5 °C	-24.5 °C	0	0	14
April	17.5 °C	7.0 °C	11.7 °C	28.6 °C	-6.1 °C	2	0	3
May	22.7 °C	12.8 °C	17.4 °C	34.8 °C	-2.4 °C	11	1	0
June	27.2 °C	17.8 °C	22.3 °C	38.6 °C	6.3 °C	22	7	0
July	29.0 °C	19.7 °C	24.2 °C	38.0 °C	10.9 °C	28	11	0
August	28.4 °C	19.1 °C	23.6 °C	35.7 °C	10.7 °C	27	9	0
September	25.1 °C	15.5 °C	20.0 °C	36.8 °C	3.3 °C	16	4	0
October	18.3 °C	9.4 °C	13.3 °C	31.9 °C	-1.8 °C	3	0	0
November	10.8 °C	3.0 °C	6.4 °C	24.6 °C	-14.7 °C	0	0	9
December	4.8 °C	-2.3 °C	0.7 °C	21.0 °C	-26.7 °C	0	0	20

Rain, sun and wind month by month

Month	Rainfall	Wet days	Daylight	Cloud cover	Humidity	Wind
January	79 mm	10	9.7 h/day	70 %	73 %	20 km/h
February	69 mm	8	11 h/day	69 %	70 %	20 km/h
March	97 mm	11	12 h/day	64 %	68 %	20 km/h
April	122 mm	12	13 h/day	62 %	67 %	21 km/h
May	124 mm	14	14 h/day	61 %	70 %	18 km/h
June	107 mm	12	15 h/day	56 %	70 %	16 km/h
July	94 mm	11	15 h/day	51 %	71 %	14 km/h
August	72 mm	9	14 h/day	49 %	70 %	14 km/h
September	74 mm	7	12 h/day	46 %	68 %	15 km/h
October	82 mm	9	11 h/day	53 %	68 %	18 km/h
November	87 mm	9	10.0 h/day	62 %	71 %	19 km/h
December	78 mm	10	9.4 h/day	70 %	75 %	19 km/h

How Indianapolis compares

The same four figures for nearby destinations, so the numbers above have something to be read against. Summer high is the warmest month's average high; winter low is the coldest month's average low.

Destination	Summer high	Winter low	Rain per year	Days above 25 °C
Indianapolis	29 °C	-5.3 °C	1,085 mm	109
Cincinnati · United States	29 °C	-4.2 °C	1,085 mm	112
Louisville · United States	31 °C	-2.4 °C	1,170 mm	131
Fort Wayne · United States	28 °C	-6.9 °C	972 mm	91

Where Indianapolis ranks

Ranking	Position	Value
Places with the best weather in North America in September	18th of 50	91/100
The coolest places in North America in January	46th of 50	2.6 °C
The coolest places in North America in December	47th of 50	4.8 °C

Planning a trip? See the best time to visit Indianapolis.

QuestionsCommon questions about Indianapolis’s climate

When is the best time to visit Indianapolis?

That depends on what you want, so the honest answer is a comparison rather than a single month. May, June, September sit closest to 20 °C on average, July is the warmest month and February the driest. The month-by-month table above has the full picture.

How hot does Indianapolis get?

In July, the warmest month, daily highs average 29 °C. About 32 days a year pass 30 °C. The highest value in the 1991–2020 record is 39 °C.

How cold does it get in winter?

Nights average -5.3 °C in January, the coldest month. A normal year has 92 nights below freezing.

Which month is wettest in Indianapolis?

May, averaging 124 mm over 14 days with rain. The driest month is February with 69 mm. The year as a whole averages 1,085 mm.

Are these figures a forecast?

No. They are 1991–2020 climate normals: the average of thirty years, which describes what a month is usually like in Indianapolis rather than what any particular week will bring. Individual years can differ substantially from the normal.

Data sources and method

ERA5 / ERA5-Land reanalysis — Copernicus Climate Change Service (C3S), ECMWF. Copernicus Licence
Open-Meteo — Open-Meteo.com. CC BY 4.0
NOAA OISST v2.1 — NOAA Physical Sciences Laboratory. Public domain
GeoNames — GeoNames.org. CC BY 4.0

Normal period: 1991–2020
Data point: 39.768°, -86.158° , 218 m above sea level (the coordinates the reanalysis values are taken for)
Dataset version: era5-1991-2020-scores1.1
Last processed: 1 August 2026

Measured values come from ERA5 reanalysis and are reproduced unchanged. Calculated by us: monthly rankings, daylight hours, beach and comfort scores. Full formulas are on the methodology page.

Contains modified Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.