Summary of Climatic Data by Month September 2020 - August 2021 and Averages for the Years 1916-2021 at the
Northern Agricultural Research Center, Havre, MT
Month Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Year
Year 2020 2020 2020 2020 2021 2021 2021 2021 2021 2021 2021 2021  
Precipitation (inches)   Total
   Current Year 1.72 0.99 1.11 0.07 0.02 0.59 0.20 0.51 3.02 0.23 0.32 1.22 10.00
   Average (1916- 2021) 1.18 0.69 0.45 0.45 0.43 0.35 0.53 0.99 1.85 2.53 1.41 1.17 12.02
   Difference +0.54 +0.30 +0.66 -0.38 -0.41 +0.24 -0.33 -0.48 +1.17 -2.30 -1.09 +0.05 -2.02
Temperature (°F)   Average
   Current Year 58.8 39.1 32.1 29.8 28.2 10.0 37.6 42.6 49.8 66.9 74.7 67.7 44.8
   Average (1916 - 2021) 56.4 45.5 30.2 19.7 15.9 19.7 30.1 43.5 53.9 61.9 69.3 67.4 42.8
   Difference +2.4 -6.4 +1.9 +10.1 +12.3 -9.7 +7.5 -0.9 -4.1 +5.0 +5.4 +0.3 +2.0
Last killing frost in springa
Spring, 2021: May 23 (32.0 °F)
Average (1916 - 2021): May 14
First killing frost in falla
Fall, 2021: September 17 (29.9 °F)
Average (1916 - 2021): Septembper 20
Frost-free period
2021: 117 days
Average (1916 - 2021): 130 days
Temperature Extremes
Maximum summer temperature: 101.8 °F (June 16, 2021)
Minimum winter temperaturege -34.3 °F (February 14, 2021)
Growing degree days (base 50)
May 23 - September 17, 2021: 2005.6 GDD
May 1 - September 30, 2021: 2327.9 GDD
Average (1916 - 2021): 2179.2 GDD

aIn this summary 32 °F is considered a killing frost.