Month Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Crop Year
Year 2017 2017 2017 2017 2018 2018 2018 2018 2018 2018 2018 2018
Precipitation (inches) Total
Current Year 1.08 0.95 0.66 1.90 0.20 2.59
1.25
0.24 1.10 2.50 0.18 0.50 13.15
Average (1916-2018) 1.16 0.69 0.44 0.46 0.43 0.34 0.54 1.00 1.84 2.54 1.43 1.18 12.05
Difference -0.08 0.26 0.22 1.44 -0.23 2.25 0.71 -0.76 -0.74 -0.04 -1.25 -0.68 1.10
Mean Temperature (
o
F)
Average
Current Year 57.5 43.0 28.5 21.2 14.6 1.9 20.8 36.0 58.9 63.3 69.5 67.2 40.2
Average (1916-2018) 56.3 45.6 30.2 19.5 15.6 19.9 30.1 43.6 54.0 61.8 69.3 67.3 42.8
Difference 1.1 -2.7 -1.6 1.7 -1.1 -18.0 -9.3 -7.6 4.9 1.5 0.2 -0.1 -2.6
Last killing frost in spring*
2018 May 14th (29.0˚)
Ave. 1916-2018 May 14th
First killing frost in fall*
2018 September 28th (28.9˚)
Ave. 1916-2018 September 20th
Frost free period
2018 137 days
Ave. 1916-2018 130 days
Growing degree days (base 50)
May 14-Sept. 28, 2018 1930.1
May 1-Sept. 30, 2018 2111.7
Ave. 1951-2018 (May 1 - Sept. 30) 2181.3
Maximum summer temperature 102.6˚ F on August 2, 2018
Minimum winter temperature -33.7˚ F on February 12, 2018
*In this summary 32
o
is considered a killing frost.
Summary of climatic data by months for the 2017-2018 crop year (September to August) and averages for the period 1916-2018 at the
Northern Agricultural Research Center. Havre, Montana.
