Climate Comfort Score
59/100
Moderate
NOAA 1991–2020 normals 51°F annual avg Public-domain federal data
Decatur, IN Climate
Pulled from NOAA NCEI 1991–2020 normals →: average temperature, precipitation, and comfort score
- 51°F
- Avg annual temp
- 59/100
- Comfort score
- 40.6"
- Annual precip
- 179d
- Growing season
30-year climate normals from 1 weather station (1991-2020).
The climate verdict for Decatur
Decatur, Indiana averages 51°F a year and scores 59/100 on the comfort index - moderate, milder than 39% of U.S. cities.
- 51°F
- average temperature, NOAA 1991-2020 normal
- 59/100
- comfort score, milder than 39% of U.S. cities
- 40.6"
- annual precipitation · 28" snow
- 179 days
- frost-free days per growing season
Based on NOAA U.S. Climate Normals (1991–2020) - 30-year averages describing the typical year, not a forecast.
Avg Temperature
51°F (10°C)
Avg High
60°F
Avg Low
41°F
Annual Precip
40.6"
Annual Snow
28.1"
Comfort Score
59/100
Moderate
Avg Annual Temperature
51°F
30-year mean (NOAA NCEI)
Annual Precipitation
40.6"
Plus 28.1" of snow
Comfort score vs national 100-point ceiling (Decatur) 59.0%
National median (63)
PlainClimate composite, temperature mildness, humidity, precipitation, extreme-weather frequency. Moderate for the Decatur area.
How Decatur compares to every U.S. city
Decatur's comfort score vs. all U.S. cities
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
59 Top 61% higher than 39% of 6,915 US cities
Each bar is a band; taller bars hold more US cities. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
Source NOAA U.S. Climate Normals, PlainClimate comfort index · 1991–2020
Warming context for Decatur
MethodologyDecatur's NOAA 1991-2020 normal sits inside a longer story: U.S. land temperatures have been tracking (and drifting from) the global mean since 1900, and the chart below shows that spread, with the most recent decade running warmer than the 30-year mean.
- United States land mean (NOAA NCEI) +0.11 °C/decade
- Global anomaly (NASA GISTEMP) +0.11 °C/decade
- Paris Agreement thresholds 1.5°C / 2.0°C
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Snow | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|---|
| January | 33°F (1°C) | 18°F (-8°C) | 26°F (-4°C) | 2.5" | 9.2" | 27.2 | 0.0 |
| February | 36°F (2°C) | 20°F (-6°C) | 28°F (-2°C) | 2.1" | 7.5" | 25.1 | 0.0 |
| March | 48°F (9°C) | 29°F (-2°C) | 38°F (3°C) | 2.8" | 4.2" | 21.5 | 0.0 |
| April | 61°F (16°C) | 39°F (4°C) | 50°F (10°C) | 4.1" | 0.5" | 8.1 | 0.0 |
| May | 72°F (22°C) | 50°F (10°C) | 61°F (16°C) | 4.8" | 0.0" | 0.3 | 0.9 |
| June | 81°F (27°C) | 60°F (16°C) | 71°F (21°C) | 4.6" | 0.0" | 0.0 | 3.9 |
| July | 84°F (29°C) | 63°F (17°C) | 73°F (23°C) | 4.3" | 0.0" | 0.0 | 6.4 |
| August | 82°F (28°C) | 61°F (16°C) | 71°F (22°C) | 4.0" | 0.0" | 0.0 | 3.9 |
| September | 77°F (25°C) | 53°F (12°C) | 65°F (18°C) | 3.0" | 0.0" | 0.0 | 2.3 |
| October | 64°F (18°C) | 42°F (6°C) | 53°F (12°C) | 2.9" | 0.0" | 3.9 | 0.1 |
| November | 50°F (10°C) | 33°F (0°C) | 41°F (5°C) | 3.0" | 1.2" | 15.8 | 0.0 |
| December | 38°F (3°C) | 24°F (-4°C) | 31°F (0°C) | 2.6" | 5.5" | 25.1 | 0.0 |
Monthly Precipitation
Average monthly rainfall and snowfall
January 2.5"
Snow: 9.2"
10.9 days with precipitation
February 2.1"
Snow: 7.5"
9.0 days with precipitation
March 2.8"
Snow: 4.2"
11.2 days with precipitation
April 4.1"
Snow: 0.5"
13.0 days with precipitation
May 4.8"
12.9 days with precipitation
June 4.6"
11.7 days with precipitation
July 4.3"
10.0 days with precipitation
August 4.0"
9.3 days with precipitation
September 3.0"
8.4 days with precipitation
October 2.9"
9.9 days with precipitation
November 3.0"
Snow: 1.2"
10.4 days with precipitation
December 2.6"
Snow: 5.5"
10.7 days with precipitation
Frost Dates & Growing Season
First Fall Freeze
October 19
50% probability date
Last Spring Freeze
April 23
50% probability date
Growing Season
179 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
6,010
Higher = more heating needed
Cooling Degree Days
818
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
What Decatur's climate means for you
Decatur runs 51°F a year - peaking in July, coldest in January.
- Gardeners get about 179 frost-free days, with the last spring freeze near April 23 - plan the planting calendar around it, not the regional average.
- Energy bills track 6,010 heating and 818 cooling degree days a year, higher means the furnace or AC runs more.
- Comparing places to live? Line this city up against nearby cities and the national rankings. See rankings
These are 30-year NOAA normals (1991–2020) - the typical year, not a forecast for any specific season.
Climate Guides
Climate Insight: Decatur, IN
The NOAA 1991–2020 climate normals describe Decatur, Indiana as a location with an annual average temperature of 51°F, ranging from a mean daily high of 60°F to a mean daily low of 41°F. July is typically the warmest month of the year, while January is the coldest. These thirty-year averages, computed from station USC00122096, smooth out year-to-year variability and give a baseline expectation for typical conditions in any given month.
Beyond temperature, Decatur averages 40.6 inches of precipitation annually, with 28.1 inches typically falling as snow - a real factor for anyone planning to live, garden, or travel here. The frost-free season averages 179 days, which directly shapes the planting calendar and growing potential for the area, with the last spring freeze near April 23 and the first fall freeze near October 19. Turning to energy use, 6,010 heating degree days and 818 cooling degree days tell the story of how often furnaces and air conditioners run during a normal year.
On PlainClimate's composite comfort index, Decatur scores 59/100 (Moderate), a blended measure that weighs temperature mildness, precipitation moderation, and extreme-weather frequency against one another. For planning purposes, look to the monthly tables above: shoulder seasons bring the mildest highs and lows, summer brings July-driven heat, and deep winter brings January-driven cold. Treat every figure here as a thirty-year average rather than a forecast - individual years routinely run warmer, cooler, wetter, or drier than the normal.
Frequently Asked Questions
What is the average temperature in Decatur, IN? ▼
The average annual temperature in Decatur, Indiana is 51°F. The warmest month averages 84°F (29°C) and the coldest averages 18°F (-8°C).
How much rain does Decatur get? ▼
Decatur receives 40.6 inches of precipitation annually, including 28.1 inches of snow. Based on NOAA 30-year climate normals (1991-2020).
What is the comfort score for Decatur? ▼
Decatur has a climate comfort score of 59/100 (Moderate), milder than 39% of U.S. cities in the PlainClimate database.
When is the growing season in Decatur? ▼
Decatur has approximately 179 frost-free days per year, with the last spring freeze around April 23 and the first fall freeze around October 19.
How much energy does heating and cooling require in Decatur? ▼
Decatur has 6,010 heating degree days and 818 cooling degree days annually, a heating-dominated climate. See our <a href="/guides/reading-weather-data/" class="underline hover:text-brand-600">guide to reading weather data</a> for what these figures mean.
Where does this Decatur climate data come from? ▼
NOAA U.S. Climate Normals v1.0.1 (1991-2020), from weather station USC00122096 near Decatur.
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). Station: USC00122096. For informational purposes only.
Read our methodology - how this data is sourced, computed, and verified.
Related
Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainClimate Editorial
Every figure on PlainClimate is rendered directly from NOAA 1991-2020 U.S. Climate Normals data, no number is typed in by an editor. This page draws directly on NOAA 1991-2020 U.S. Climate Normals data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.