Bloomington, Indiana climate: Normal weather by month, frost dates and records
Bloomington's normal year runs from 22°F January nights to 85°F July afternoons, with 46.9 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 12.1°C, January lows of −6°C, July highs of 29°C, 1,192 mm of precipitation a year.
- NOAA stationBloomington Monroe County Airport
- Station IDUSW00003893
- Location39.13°N 86.62°W
- Elevation844 ft (257 m)
- From the center5 miles
- Population79,986
On October 14, the normal high in Bloomington is 68°F and the normal low 44°F, and the chance of measurable rain or snow is 36%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Bloomington.
- Jan 39° 22°
- Feb 43° 25°
- Mar 54° 33°
- Apr 66° 43°
- May 74° 53°
- Jun 82° 62°
- Jul 85° 64°
- Aug 84° 62°
- Sep 78° 55°
- Oct 67° 44°
- Nov 53° 34°
- Dec 42° 27°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in Bloomington each month?
July is the warmest month, with normal highs of 85°F; January the coldest, with normal lows of 22°F. The most precipitation falls in June (5.09 in), the least in February (2.67 in).
Each month has its own page with the day-by-day normals, the month's records and its recent years:
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 39°F | 22°F | 30.3°F | 3.38 | 11 | <1 | 25 | 9 h 40 min |
| February | 43°F | 25°F | 33.8°F | 2.67 | 11 | <1 | 23 | 10 h 40 min |
| March | 54°F | 33°F | 43.3°F | 3.82 | 11 | <1 | 16 | 11 h 50 min |
| April | 66°F | 43°F | 54.3°F | 4.94 | 13 | <1 | 4 | 13 h 10 min |
| May | 74°F | 53°F | 63.8°F | 4.47 | 15 | 1 | <1 | 14 h 20 min |
| June | 82°F | 62°F | 72.0°F | 5.09 | 14 | 4 | <1 | 14 h 50 min |
| July | 85°F | 64°F | 74.7°F | 4.89 | 14 | 7 | <1 | 14 h 40 min |
| August | 84°F | 62°F | 73.3°F | 3.34 | 11 | 6 | <1 | 13 h 40 min |
| September | 78°F | 55°F | 66.5°F | 3.60 | 11 | 3 | <1 | 12 h 30 min |
| October | 67°F | 44°F | 55.3°F | 3.70 | 11 | <1 | 4 | 11 h 10 min |
| November | 53°F | 34°F | 43.7°F | 3.73 | 10 | <1 | 14 | 10 h |
| December | 42°F | 27°F | 34.4°F | 3.29 | 12 | <1 | 23 | 9 h 30 min |
| Year (annual) | 64°F | 44°F | 53.8°F | 46.92 | 143 | 20 | 108 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | 4°C | −6°C | −0.9°C | 86 mm |
| February | 6°C | −4°C | 1.0°C | 68 mm |
| March | 12°C | 0°C | 6.3°C | 97 mm |
| April | 19°C | 6°C | 12.4°C | 125 mm |
| May | 24°C | 12°C | 17.7°C | 114 mm |
| June | 28°C | 17°C | 22.2°C | 129 mm |
| July | 29°C | 18°C | 23.7°C | 124 mm |
| August | 29°C | 17°C | 22.9°C | 85 mm |
| September | 26°C | 13°C | 19.2°C | 91 mm |
| October | 19°C | 7°C | 12.9°C | 94 mm |
| November | 12°C | 1°C | 6.5°C | 95 mm |
| December | 6°C | −3°C | 1.3°C | 84 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. Bloomington's own co-op station Bloomington Indiana University does: 18 inches of snow in a normal year (see the other stations below).
Source: NOAA NCEI 1991-2020 monthly normals, station USW00003893; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
When is the best weather to visit Bloomington?
Normal highs sit between 65°F and 85°F in April, May, June, July, August, September and October. Of those, October has the fewest days with rain (11).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USW00003893.
When is the last frost in Bloomington?
In Bloomington, the last spring frost (32°F) comes after April 17 in half of years and after May 5 in one year in ten; the first autumn frost comes before October 22 in half of years and before October 8 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- April 171 year in 10 after May 5; 9 in 10 after April 3
- First autumn frost, half of years before
- October 221 year in 10 before October 8; 9 in 10 before November 2
NOAA puts the median frost-free season at 185 days, and the season without a hard freeze (28°F) at 208 days.
A hard freeze (28°F) comes after April 4 in half of springs and before November 1 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Bloomington in zone 6b across its 2 ZIP code areas (6b in 47406, the largest). By the map's own method, the average of each year's coldest night over 1991-2020, Bloomington's NOAA station is in zone 6a: the coldest night of a typical year reaches −5°F (21 complete years); the map interpolates between stations and terrain, so the station and the ZIP area can differ by half a zone.
Frost dates for every NOAA station in Indiana · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USW00003893; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
What hardiness zone is each Bloomington ZIP code in?
The USDA's 2023 map gives each ZIP code area one zone. Bloomington's 2 ZIP code areas are all in zone 6b. Each ZIP's frost dates are in the frost tool.
Source: USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; ZIP areas in the place: Census Bureau 2020 ZCTA-to-place relationship file. A ZIP area counts when at least a tenth of its land (and 0.5 km²) lies in the place.
How hot and how cold does it get in Bloomington?
In a normal year in Bloomington, 20 days a year reach 90°F (1 of them 100°F or more), 108 nights fall to 32°F or colder and 143 days bring measurable precipitation.
- Days at 90°F or more
- 20a normal year
- Days at 100°F or more
- 1a normal year
- Nights at 32°F or colder
- 108a normal year
- Days that stay below freezing
- 23high of 32°F or less
- Days with 0.01 inch of precipitation
- 143a normal year
The highest temperature in this station's record (since 1998) is 106°F, on July 7, 2012; the lowest is −22°F, on January 31, 2004.
The wettest calendar year on that record is 2008, with 63.81 in.
Source: NOAA NCEI 1991-2020 annual normals, station USW00003893; records: ACIS (NOAA Regional Climate Centers), station USW00003893. Records use complete months only; a month missing more than three days is left out.
How sunny is Bloomington?
Over a year 73% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Bloomington, 4.0 kWh per square metre a day. August is the sunniest month (81%) and December the cloudiest (59%). Among the 459 U.S. places of 50,000 or more, that ranks tied 352nd (with 32 others) in sunshine.
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 61% | 1.8 |
| February | 63% | 2.6 |
| March | 66% | 3.7 |
| April | 71% | 4.8 |
| May | 72% | 5.5 |
| June | 79% | 6.3 |
| July | 80% | 6.1 |
| August | 81% | 5.5 |
| September | 80% | 4.6 |
| October | 73% | 3.2 |
| November | 69% | 2.2 |
| December | 59% | 1.6 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How much heating and cooling does Bloomington need?
A normal year in Bloomington brings 5,083 heating degree days, 5% fewer than the median U.S. place (5,373), and 1,026 cooling degree days, 13% more than the median (908). Seven months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 3,622 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,075 | 0 |
| February | 875 | 0 |
| March | 678 | 3 |
| April | 337 | 17 |
| May | 123 | 85 |
| June | 12 | 224 |
| July | 2 | 301 |
| August | 4 | 263 |
| September | 70 | 113 |
| October | 320 | 19 |
| November | 639 | 1 |
| December | 949 | 0 |
| Year (annual) | 5,083 | 1,026 |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00003893. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
Has Bloomington been warmer than normal lately?
2024 averaged 57.0°F, 3.2°F above the 1991-2020 normal of 53.8°F. 3 of the 3 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 55.3°F | +1.5°F | – |
| 2023 | 56.2°F | +2.4°F | 36.67 |
| 2024 | 57.0°F | +3.2°F | 42.93 |
Source: observed years: ACIS, station USW00003893. A year counts only with all twelve months complete.
How does Bloomington's climate compare?
Bloomington is warmer than 71 of the other 98 places with their own NOAA record in Indiana, and wetter than 65. Across the 7,247 U.S. stations with normals, its annual mean of 53.8°F is warmer than 56%.
In the Köppen classification computed from these normals, Bloomington is Dfa: continental, no dry season, hot summer. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Which places near Bloomington share this climate record?
5 places have no NOAA station with 1991-2020 normals of their own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- Ellettsville, IN6,829 people · 7 mi N
- Smithville-Sanders, IN3,228 people · 8 mi SE
- Stanford, IN463 people · 4 mi SW
- Harrodsburg, IN315 people · 9 mi SE
- Solsberry, IN182 people · 9 mi SW
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
What do Bloomington's other NOAA stations record?
One more NOAA station keeps 1991-2020 normals in or near Bloomington. This page uses Bloomington Monroe County Airport; the other differs by site and elevation:
| Station | From the center | Elevation | Year | Jan low | Jul high | Precip. | Snow | Last frost |
|---|---|---|---|---|---|---|---|---|
| Bloomington Indiana University USC00120784 | 1 mi N | 830 ft | 53.3°F | 21°F | 85°F | 49.4 | 18 | April 15 |
Source: NOAA NCEI 1991-2020 normals for each station. Last frost: the median last spring date of 32°F.
Questions about Bloomington's climate
What is the coldest month in Bloomington?
January, with a normal high of 39°F and a normal low of 22°F. The warmest is July (85°F by day, 64°F at night).
Does it snow in Bloomington?
Yes. NOAA publishes no 1991-2020 snowfall normal for Bloomington's NOAA station; Bloomington's own co-op station Bloomington Indiana University records 18 inches of snow in a normal year.
What is the rainiest month in Bloomington?
June, with 5.09 in of precipitation in a normal year; the driest is February with 2.67 in.
What plant hardiness zone is Bloomington in?
The USDA's 2023 map puts Bloomington in zone 6b across its 2 ZIP code areas (6b in 47406, the largest). By the same method at Bloomington's NOAA station, the coldest night of a typical year reaches −5°F (21 years, 1991-2020): zone 6a.
How late can frost come in Bloomington?
In half of years the last 32°F night comes after April 17; in one year in ten it comes after May 5. Waiting until May 5 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Bloomington in OctoberThis month day by day, its records and recent years
- Indiana climateThe statewide normals and every place in the state
- Spencer, IN13 miles from this station, 52.8°F a year
- Bedford, IN17 miles from this station, 54.3°F a year
- Oolitic, IN17 miles from this station, 53.0°F a year
- Martinsville, IN21 miles from this station, 51.7°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made