Montana State University

Montana Climate Summary - By County

All of the information is APPROXIMATE.  Expect the actual growing season to vary by plus or minus 2 weeks from year to year.  Actual site conditions also play an important role in growing season characteristics.

County

Station

Last in Spring

First in Fall

Growing Season (days)

Annual Precipitation (inches)

Beaverhead

Bowen

*

*

-----

12.14

 

Dillon

May 22

Sept. 12

113

16.67

 

Grant

June 13

Sept. 9

88

10.79

 

Lima

June 11

Sept. 6

87

9.27







Big Horn

Busby

May 24

Sept. 16

115

12.98

 

Crow Agency

May 13

Sept. 25

135

15.33

 

Foster (near)

May 18

Sept. 18

123

11.59

 

Wyola

May 22

Sept. 25

126

13.43







Blaine

Chinook

May 13

Sept. 19

129

13.22

 

Clear Creek

May 26

Sept. 23

120

16.41

 

Harlem

May 16

Sept. 21

128

12.78







Broadwater

Townsend (near)

-----

-----

101

10.10







Carbon

Bridger

May 18

Sept. 18

123

10.42

 

Red Lodge (near)

June 4

Sept. 12

100

18.38







Carter

Ekalaka

May 19

Sept. 23

127

13.17







Cascade

Adel (near)

June 8

Sept. 5

89

24.20

 

Cascade (near)

May 20

Sept. 17

120

15.83

 

Great Falls

May 9

Sept. 25

139

15.21







Chouteau

Big Sandy

May 15

Sept. 20

128

12.11

 

Carter

May 20

Sept. 15

118

12.10

 

Fort Benton

May 11

Sept. 25

137

13.11

 

Geraldine (near)

May 8

Sept. 28

143

15.30

 

Highwood

May 23

Sept. 18

118

18.90

 

Kenilworth (near)

May 25

Sept. 18

116

12.00

 

Lytle

May 12

Sept. 25

136

13.13







Custer

Garland

May 18

Sept. 23

128

11.81

 

Knowlton (near)

May 15

Sept. 22

130

15.76

 

Miles City

April 30

Oct. 5

158

13.16







Daniels

Scobey

May 24

Sept. 22

121

11.45







Dawson

Glendive

May 13

Sept. 24

134

14.03

 

Paxton (near)

May 7

Sept. 28

144

11.09







Deer Lodge

Anaconda

June 8

Sept. 14

98

14.24

 

East Anaconda

May 27

Sept. 21

117

13.27







Fallon

Baker

May 9

Sept. 25

139

14.21

 

Plevna (near)

May 18

Sept. 27

132

13.46







Fergus

Denton

May 15

Sept. 24

132

14.13

 

Lewistown

May 28

Sept. 13

108

17.87

 

Pinegrove

June 3

Sept. 13

102

19.78

 

Valentine

May 17

Sept. 19

125

10.90

 

Winifred

May 15

Sept. 23

131

11.64







Flathead

Belton

May 28

Sept. 17

112

26.25

 

Columbia Falls

June 1

Sept. 8

99

20.65

 

Kalispell

May 5

Oct. 1

149

14.50

 

Pleasant Valley (near)

*

*

-----

18.05







Gallatin

MSU-Bozeman

May 24

Sept. 16

115

17.39

 

Flathead Creek

June 4

Sept. 1

89

21.82

 

Hebgen Dam

June 15

Sept. 11

88

22.84

 

Three Forks

May 30

Sept. 19

112

11.86







Garfield

Jordan

May 19

Sept. 21

125

11.62

 

Sentinel Butte Pass

May 7

Oct. 2

148

14.53

 

Snowbelt

May 17

Sept. 28

134

13.87







Glacier

Babb (near)

May 29

Sept. 8

102

19.43

 

Browning

June 6

Sept. 7

93

13.92

 

Cut Bank

May 23

Sept. 17

117

11.24







Golden Valley

Emory

May 22

Sept. 14

115

14.90

 

Ryegate

-----

-----

-----

14.82







Granite

Drummond (near)

-----

-----

-----

10.55

 

Phillipsburg

June 9

Sept. 4

87

14.75







Hill

Havre

May 11

Sept. 22

134

13.07







Jefferson

Boulder

June 11

Sept. 6

87

12.60

 

Dry Land

-----

-----

-----

-----

 

Experiment Station

May 25

Sept. 20

118

12.67

 

Pipestone Dam

June 15

Sept. 6

83

11.97

 

Renova (near)

May 26

Sept. 11

108

11.34







Judith Basin

Hobson

-----

-----

-----

15.45

 

Stanford

May 23

Sept. 28

128

14.57

 

Utica

May 25

Sept. 18

116

16.45







Lake

Dayton

May 18

Sept. 25

130

14.09

 

Polson

May 12

Sept. 27

138

14.56

 

St. Ignatius

May 21

Sept. 23

125

15.13







Lewis & Clark

Augusta

May 29

Sept. 10

104

14.35

 

Big Ox

June 3

Sept. 8

97

19.08

 

Canyon Ferry

May 13

Sept. 22

132

10.99

 

Chessman Res

-----

-----

-----

21.31

 

East Helena

May 14

Sept. 22

131

9.39

 

Helena

May 2

Oct. 2

153

12.54

 

Helena Valley

-----

-----

101

8.47

 

Holter

May 13

Sept. 23

133

13.24

 

Sun River Canyon

May 27

Sept. 21

117

15.52







Liberty

Chester

May 25

Sept. 7

105

10.53

 

Kinread

May 25

Sept. 15

113

10.82

 

Lothair

May 15

Sept. 19

127

11.06







Lincoln

Fortine

May 29

Sept. 8

102

17.43

 

Libby

June 1

Sept. 9

100

18.81

 

Upper Yaak River

*

*

-----

19.78







Madison

Conway's Ranch

*

*

-----

16.38

 

Ennis

June 2

Sept. 11

101

10.69

 

Norris (near)

May 15

Sept. 29

137

17.05

 

Virginia City

May 30

Sept. 18

111

12.98







McCone

Circle (near)

May 23

Sept. 16

116

16.09

 

Vida (near)

May 13

Sept. 25

135

15.05







Meagher

Copper

June 6

Aug. 29

84

15.95

 

Findon

May 22

Sept. 22

123

17.55

 

Fort Logan

-----

-----

-----

11.70

 

Loweth

June 8

Sept. 9

93

12.15

 

White Sulphur Springs

May 29

Sept. 14

108

14.19







Mineral

Haugan

June 11

Aug. 30

80

27.63

 

Saltese

-----

-----

-----

34.24

 

Superior

June 2

Sept. 11

101

15.54







Missoula

Missoula

May 18

Sept. 23

128

14.01







Musselshell

Melstone

May 10

Sept. 25

138

11.73

 

Roundup

May 9

Sept. 27

141

12.26







Park

Livingston

May 17

Sept. 21

127

14.67







Petroleum

Flatwillow (near)

May 18

Sept. 25

130

11.88







Phillips

Malta

May 14

Sept. 24

133

13.47

 

Fork (near)

May 24

Sept. 13

112

12.97

 

Zortman

-----

-----

-----

17.51







Pondera

Conrad

May 21

Sept. 19

121

11.63

 

Valier

May 17

Sept. 23

129

12.26







Powder River

Biddle

May 23

Sept. 21

121

15.11







Powell

Deer Lodge

June 5

Sept. 9

96

10.27

 

Elliston

-----

-----

-----

21.23

 

Ovando

June 8

Aug. 25

78

17.40







Prairie

Fallon

May 19

Sept. 18

122

13.36

 

Mildred

May 14

Sept. 25

134

12.03







Ravalli

Como

May 22

Sept. 26

127

15.08

 

Darby (near)

May 20

Sept. 16

119

16.25

 

Hamilton

May 16

Sept. 23

130

11.31

 

Stevensville

May 25

Sept. 15

113

12.22

 

Sula

-----

-----

-----

16.57

 

Sunset Orchards

May 20

Sept. 21

124

12.86

 

Victor (near)

May 23

Sept. 22

122

13.06







Richland

Culbertson (near)

May 19

Sept. 18

122

12.28

 

Savage

May 18

Sept. 22

127

13.08

 

Sidney

May 18

Sept. 21

126

14.93







Roosevelt

Poplar

May 16

Sept. 18

125

12.67







Rosebud

Ashland (near)

May 9

Sept. 28

142

14.51

 

Colstrip

May 15

Sept. 24

132

13.81

 

Forsyth

May 16

Sept. 27

134

12.86

 

Ingomar (near)

May 20

Sept. 26

129

10.24

 

Rock Springs (near)

May 17

Sept. 24

130

13.08







Sanders

Heron

May 30

Sept. 6

99

32.45

 

Lonepine

May 22

Sept. 19

120

10.10

 

Plains

May 30

Sept. 20

113

14.08

 

Thompson Falls

May 18

Sept. 21

126

19.98

 

Trout Creek (near)

June 4

Sept. 4

92

28.83







Sheridan

Medicine Lake (near)

May 26

Sept. 17

114

12.71

 

Outlook

May 23

Sept. 21

121

12.45







Silver Bow

Butte

May 29

Sept. 16

110

13.51







Stillwater

Busteed

May 22

Sept. 21

122

14.51

 

Mystic Lake

May 26

Sept. 20

117

22.68

 

Nye

-----

-----

-----

21.55







Sweet Grass

Big Timber

May 20

Sept. 20

123

14.61







Teton

Blackleaf

June 4

Aug. 30

87

16.92

 

Choteau

May 26

Sept. 15

112

11.79

 

Fairfield

May 19

Sept. 20

124

11.53







Toole

Dunkirk (near)

May 22

Sept. 19

120

12.36

 

Goldbutte

May 24

Sept. 19

118

13.00

 

Knoble's Ranch

May 23

Sept. 25

125

14.51

 

Shelby

May 27

Sept. 14

110

11.50







Treasure

Sarpy Creek

May 22

Sept. 24

125

10.88







Valley

Frazer

May 16

Sept. 20

127

12.07

 

Glasgow

May 19

Sept. 19

123

13.21

 

Lustre (near)

-----

-----

-----

11.43

 

Opheim

May 24

Sept. 19

118

9.56







Wheatland

Harlowtown (near)

June 2

Sept. 6

96

11.74







Wibaux

Wibaux

May 25

Sept. 13

111

15.71







Yellowstone

 

May 15

Sept. 20

125

13.00