Decatur (IN) monthly weather averages

Average daytime temperature

The bar chart below shows the average monthly peak daytime temperatures at Decatur

Decatur average temperature chart (Celsius) Decatur average temperature chart (Fahrenheit)
Average monthly temperatures in Decatur (degrees centigrade and fahrenheit)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
°C -0.4 1.6 8.5 15.5 21.9 27.2 29.2 28 24.4 17.5 9.7 2.5
°F 31.3 34.9 47.3 59.9 71.5 81 84.5 82.3 75.9 63.4 49.5 36.4

Please note: these are the average peak daytime temperatures (usually around mid-afternoon) so do not show daytime / night highs and lows. To see the daily range of temperatures have a look at the temperature max / min chart below.

Average rainfall & rainy days

The graph below shows the average rainfall and number of rainy days per month.

Decatur monthly rainfall chart (mm) Decatur monthly rainfall chart (inches)
Average monthly rainfall in Decatur (mm and inches)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
mm 57 53 77 95 90 105 96 82 77 64 77 68
inches 2.2 2.1 3 3.7 3.5 4.1 3.8 3.2 3 2.5 3 2.7
Rainy days 12 11 13 13 11 10 10 9 9 9 11 13

Average annual rainfall in Decatur: 896.033mm (352.8 inches)

Average daily sunshine

The bar chart below shows the average daily sunshine hours in Decatur

Decatur average daily sunshine chart
Average daily sunshine Decatur
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Hrs sunshine 5.1 5.9 6.8 8.5 10.1 11.5 11.4 10.4 8.9 7.1 4.4 3.8

Day / night temperatures

The graph below shows the daily range of temperatures for each month.

Decatur average minimum / maximum temperatures (Celsius) Decatur average minimum / maximum temperatures (Fahrenheit)
Maximum and minimum daily temperatures in Decatur (degrees centigrade and fahrenheit)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Min °C -9.2 -7.9 -1.8 3.6 9.6 14.9 17.2 15.8 12.1 5.7 0.7 -5.7
Max °C -0.2 1.9 8.8 15.8 22.3 27.5 29.5 28.3 24.7 17.8 10 2.7
Min °F 15.4 17.9 28.9 38.5 49.2 58.8 62.9 60.4 53.8 42.2 33.2 21.8
Max °F 23.5 26.6 38.3 49.5 60.6 70.2 73.9 71.6 65.1 53.1 41.5 29.3

Sea temperature

The graph below shows the average sea temperature.

Decatur average sea temperature chart (Celsius) Decatur average sea temperature chart (Fahrenheit)
Average sea temperature around Decatur in degrees centigrade and fahrenheit
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
°C 5.3 4.5 4.6 6.3 10.2 16.2 21.9 23.5 21.3 16.2 11.2 7.4
°F 41.6 40 40.2 43.3 50.3 61.2 71.4 74.3 70.4 61.2 52.2 45.3

Wind speed

The graph below shows the average wind speed.

Decatur average winspeed by month (km/h) Decatur average winspeed by month (mph)
Average wind speed in Decatur (mph and kmh)
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
km/h 20 19 20 19 17 15 13 13 14 16 18 19
mph 12 12 12 12 10 9 8 8 9 10 11 12

A monthly average windspeed of over 16km/h or 10mph suggests a location is fairly windy.

Relative humidity

The graph below shows the average relative humidity.

Decatur relative humidity averages
Average relative humidity in Decatur
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
75% 73% 71% 66% 66% 67% 70% 73% 73% 71% 75% 78%

Other monthly averages

UV index Best time to go?

Decatur weather stats

Decatur weather statistics
Hottest month: July 29.2°C 84.6°F
Driest month: February 53mm 2.1ins
Sunniest month: July 11.4hrs
Coldest month: January -0.4°C 31.3°F
Wettest month: June 105mm 4.1ins
Warmest sea: August 23.5°C 74.3°F
Map showing location of Decatur (40.8306, -84.92913) Decatur map pin © Google

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