1
Table
I.
Summary
of
climatic
data
by
months
for
the
1987-88
crop
year
(Sept.
to
Aug.)
and
averages
for
the
period
1909-1988
at
the
Central
Agricultural
Research
Center,
Moccasin,
Montana.
Sept.
Oct.
Nov.
Dec.
Jan.
Feb.
Mar.
1987 1987
1987
1987
1988
1988
1988
Precipitation
(inches)
Current
Year
0.58
0.06
0.18
0.31
0.60
0.95
0.64
Average
1909
to
1987-88
1.43
0.87
0.59
0.57
0.58
0.50
0.73
Mean
temperature
(0°F)
Current
Year
58.0
46.3
39.1
27.4
21.3
26.2
32.2
Average
1909
to
1987-88
54.2
44.6
32.5
24.4
20.7
24.1
29.7
Last
killing
frost
in
Spring
1988
May
4
(31
°F)
Average
1909
-
1988
---------------
May
26
First
killing
frost
in
Fall
1988
----------------------
September
11
(31°F)
1987
October
9
(24°F)
Frost
free
period
1988
----------------------
]3o
days
Average
1909
-
1988
112
days
Maximum
summer
temperature
97°F
on
June
20
Minimum
winter
temperature
16°Fon
January
7,
1988
Apri
1
1988
May
June
1988
1988
July
1988
Aug.
1988
1.94
1
.10
43.9
40.8
3.11
2.60
54.8
50.2
2.69
3.22
68.3
58.0
0.78
1.62
68.7
65.8
0.46
1.57
65.7
64.3
Total
or
Average
12.30
15.38
45.9
42.4
O
n
Table
2.
Daily
and
monthly
precipitation
in
Moccasin,
Montana.
1988.
inches
at
the
Central
Research
Center,
1
Day
Jan.
Feb.
Mar.
April
May
June
July
Aug.
Sept.
Oct.
Nov.
Dec.
n
1
.01
1
2
3
T
.09
.01
4
T
.19
.07
.03
5
.18
.57
6
7
.01
1.73
.02
.21
f*
8
.12
.01
.74
.68
.25
9
.10
.26
10
.20
.04
11
.14
T
.15
.24
12
.29
.01
.08
.02
.27
13
.01
.46
.11
14
15
.07
.11
.21
.03
.04
.07
.06
T
16
.08
17
T
.03
.06
.88
18
.12
.92
.01
19
.15
.04
.16
m
20
.04
.06
21
.03
.64
.09
.12
22
.08
.07
.02
.02
23
.03
.43
24
n
25
,34
'
26
27
T
.13
.02
.06
.16
.02
.02
28
.14
.20
.53
T
29
.01
.62
30
.16
.04
.31
31
.02
n
1988
Sum.
Total
.58
.95
.64
1
.94
3.11
2.69
.78
.46
1.78
.99
.04
.77
14.75
n
Table
3.
Summary
of
precipitation
and
snowfall
at
the
Central
Research
Center
Moccasin,
Montana.
1988.
'
Month
Precipitation-Inches
Winter
Snowfal1-Inches*
Yearly
snowfal1-Inches
Snow**
Depth
Inches
1988
80
Yr.
Ave.
1987-88
27
Yr.
Ave.
1987-88
26
Yr.
Ave.
January
0.60
0.58
12.0
13.6
12.0
13.1
10.0
February
0.95
0.50
16.0
7.2
16.0
7.2
9.0
March
0.64
0.73
9.0
10.2
9.0
10.2
3.5
Apri
I
1.94
1.10
8.5
7.9
8.5
7.9
5.0
May
3.11
2.60
0
1.9
1.9
June
2.69
3.22
0
July
0.78
1.62
0
August
0.46
1.57
0
September
1.78
1.43
0
1.0
1.0
October
0.99
0.87
3.0
5.7
5.7
5.9
3.5
November
0.04
0.58
2.5
7.6
7.6
7.8
2.5
December
0.77
0.58
12.5
11.1
12.5
11
.1
5.0
*
Winter
Snowfall
-
Sept.
thru
May
**
Highest
snow
depth
during
month
on
ground
in
1988.
f-i
a
Table
4.
Summary
of
air
temperature
and
wind
velocity
at
the
Central
Research
Center,
Moccasin,
Montana.
1988
Month
1988
Air
Temp.
°F
Max.
Min.
Mean
1911-1988
Air
Temp.
Max.
Min.
Mean
1988
Wind
Speed
MPH*
1910-1988
January
33.1
9.5
21.3
32.3
8.6
20.7
5.0
6.0
February
39.2
13.0
26.1
35.7
12.6
24.1
6.1
6.0
n
March
44.6
21.6
33.1
40.4
18.6
29.7
6.6
6.0
•
1
April
56.9
30.9
43.9
52.8
29.2
40.8
5.8
6.5
May
68.5
41.0
54.7
62.5
38.0
50.2
6.7
5.8
June
83.4
53.2
68.3
70.2
50.7
58.0
3.4
4.8
July
84.4
52.9
68.6
80.0
50.9
65.8
3.4
4.3
August
82.0
49.5
65.7
79.4
49.3
64.3
3.9
4.5
September
67.9
41.9
54.9
67.6
40.7
54.2
3.9
4.9
October
62.4
35.6
49.0
57.4
31.5
44.7
3.4
4.9
November
43.5
19.6
31.5
44.0
20.8
32.5
4.0
5.4
December
38.7
13.5
26.1
35.5
13.0
24.4
4.1
6.0
n
*
Wind
speed
average
of
24
hours
per
day.
P
Number
of
days
90°F
or
above
in
1988:
June
July
Aug.
Sept.
Total
78
Yr.
Ave.
Number
of
days
O^'F
or
under
in
1988:
9
Jan.
8
Feb.
4
Dec.
1
Total
22
78
Yr.
11
Ave.
n
9
7
4
20
28
Lowest
temperature
recorded
in
1988:
-16°F
on
January
7,
1988.
Highest
temperature
recorded
in
1988:
97°F
on
June
20,
1988.
Date
highest
wind
speed
in
1988:
17.8
MPH
on
February
21,
1988.
n
Table
5.
Summary
of
soil
temperature
at
three
soil
depths
under
bare
ground
and
sod.
Central
Research
Center,
Moccasin,
Montana.
1988
4
inch
Soil
Depth
Bare
Ground
8
inch
Soil
Depth
Bare
Ground
20
inch
Soil
Depth
4
inch
Soil
Depth
1988
23
Yr.
.
1988
23
Yr.
1988
13
Yr.
1988
23
Yr.
Month
Mean
Mean
Mean
Mean
Mean
Mean Mean
Mean
January
28.6
30.7
28.7
30.7
33.1
33.7
28.8
32.1
February
31.1
32.0
31.9
31.4
31.9
32.5
33.8
31.9
March
40.6
36.5
38.8
35.2
37.1
34.6
41.3
37.3
April
48.0
45.7
46.4
43.6
42.8
40.5
49.2
47.2
May
61.3
56.2
58.2
53.9
50.4
48.6
59.3
57.8
June
75.6
66.3
71.7
63.6
60.5
56.2
72.4
66.9
1*1
July
78.6
73.9
75.2
71.3
64.7
62.3
76.0
73.8
August
75.7
70.7
73.1
70.2
65.6
63.3
74.5
72.5
September
59.9
60.7
58.8
59.4
58.7
58.0
60.5
61.6
October
52.6
48.4
51.3
47.9
52.7
49.8
52.9
50.0
n
November
37.5
37.9
38.4
38.3
43.5
42.7
38.8
40.9
December
36.3
33.8
36.2
33.8
38.6
40.4
36.5
35.3
Low
and
high
soil
temperature
during
winter
(1987-88)
and
summer
1988
4
inch
bare:
Low
16°F
Jan.
18
&
19
High
101
°F
on
July
25,
26,30
&
31
8
inch
bare:
Low
20°F
Jan.
18
&
19
High
93°F
on
July
31
20
inch
bare:
Low
32°F
Jan.
20
High
68OF
on
July
30
&
31
4
inch
sod:
Low
230F
Jan.
4,
5
&
6
High
90°F
on
July
25,
26,
30
&
31
Dates
when
soil
first
froze
(32°F)
and
dates
when
last
thawed
(33°F)
winter
1987-88
4
inch
bare:
Froze
Dec
.
23
Thawed:
Feb.
11
8
inch
bare:
Froze
Dec
.
23
Thawed:
Feb.
11
n
20
inch
bare:
Froze
Jan
.
20
Thawed:
Feb.
18
4
inch
sod
:
Froze
Nov
.
27
Thawed:
Feb.
11
m
n
Table
6.
Inches
of
evaporation
from
a
free
water
surface.
Central
Research
Center,
Moccasin,
Montana.
1988.
Water
Evap.
-
Inches
Precipitation
-
Inches
Month
1988
1909-88
1988
1909-88
April
4.35
4.17
1.94
1.10
3.11
2.60
r
May
8.28
5.85
June
10.84
6.61
2.69
3.22
July
12.42
8.83
0.78
1.62
August
11.55
8.39
0.46
1.57
September
5.74
5.46
1.78
1.43
r
Total
53.18
39.
10
Mean
8.86
6.55
Ratio
of
Precipitation
to
Evaporation
1988:
1
inch
precipi
tation
to
4.94
evaporation
19G9-1988:
3.70
inches
Highest
daily
evaporation
in
1988:
0.66
on
July
21,
1988
