Summary of climatic data by months for the 2017-2018 crop year (October thru September) and averages for the period 1949-2018
at the Eastern Agricultural Research Center, Sidney, Montana, irrigated and dryland site.
Month
Oct
Nov
Dec
Jan
Feb
Mar
Apr
May
June
July
Aug
Sept
Year
2017
2017
2017
2018
2018
2018
2018
2018
2018
2018
2018
2018
Precipitation (inches)
Total
Current Year-Irrigated
0.94
0.19
0.37
0.24
0.32
1.40
0.58
3.63
2.49
1.80
1.02
1.21
14.19
Avg. 1949 to 2018
0.92
0.48
0.44
0.40
0.35
0.55
1.15
2.17
2.49
2.05
1.46
1.28
13.74
Current Year-Dryland
1.05
0.19
0.37
0.24
0.32
1.40
0.94
3.42
2.26
2.19
0.61
1.35
14.34
Temperature (F
o
)
Average
Ave. Maximum Temp
59.2
40.1
27.8
24.4
15.2
35.2
49.3
73.6
79.0
83.5
82.3
66.4
53.0
Ave. Minimum Temp
31.2
17.7
8.0
2.0
-7.2
16.7
25.7
47.4
53.7
55.3
51.0
41.2
28.6
Current Year Mean Temp
45.2
28.9
17.9
13.2
4.0
26.0
37.5
60.5
66.4
69.4
66.7
53.8
40.8
Avg. 1949 to 2018
46.0
30.2
18.0
13.1
19.6
30.6
44.5
56.1
64.6
70.2
68.7
58.0
43.3
Last killing frost in spring *
2018 .............................................. April 24, 2018 (28.3
o
F)
Avg. 1949 to 2018 ......................... May 15
First killing frost in fall *
2018 .............................................. September 24, 2018 (31.6
o
F)
Avg. 1949 to 2018 ......................... September 21
Frost-free period
2018 .............................................. 153
Avg. 1949 to 2018 ......................... 129
Growing degree days (base 50) **
May 1 - First killing frost ................ 2270.9
Avg. 1949 to 2018 ......................... 2249.1
Maximum summer temperature ............ August 11, 2018 (103.2⁰F)
Minimum winter temperature ................ January 1, 2018 (-35.5⁰F)
* 32
o
is considered a killing frost.
** In calculating growing degree days, 29
o
is considered a killing frost.
