National Weather Service United States Department of Commerce
Southwest Idaho and Southeast Oregon Freeze Probability Data
 
The tables list the probability of a given temperature or lower will be reached by a date. Probabilities are based on observed temperatures from 1981 through 2010. For example, Boise has a 90% chance of getting spring temperatures of 36 F on and after May 10.
 
A hard freeze is when temperatures reach or fall below 28 F.
A freeze is when temperatures reach or fall below 32 F.
 
SPRING
FALL

Boise

% Probability of Indicated Temperature or Lower on or After Date

 
90%
75%
50%
25%
10%
36 F
May 2
May 11
May 16
June 5
June 11
32 F
April 17
May 2
May 8
May 14
May 25
28 F
March 28
April 9
April 16
May 5
May 12
24 F
Feb. 17
March 2
March 12
April 9
April 21
 

Nampa

% Probability of Indicated Temperature or Lower on or After Date

 
90%
75%
50%
25%
10%
36 F
May 9
May 13
May 22
May 30
June 9
32 F
April 16
April 22
May 3
May 10
May 19
28 F
March 24
April 3
April 12
April 22
May 1
24 F
March 3
March 5
March 17
April 3
April 15
 

Emmett

% Probability of Indicated Temperature or Lower on or After Date

 
90%
75%
50%
25%
10%
36 F
May 2
May 8
May 17
May 30
June 8
32 F
April 18
April 28
May 5
May 13
May 20
28 F
March 20
March 31
April 14
April 25
May 5
24 F
March 1
March 5
March 19
April 9
April 15
 

Payette

% Probability of Indicated Temperature or Lower on or After Date

 
90%
75%
50%
25%
10%
36 F
May 1
May 5
May 12
May 24
June 3
32 F
April 16
April 19
May 2
May 12
May 14
28 F
March 24
April 5
April 12
April 23
May 6
24 F
March 3
March 10
March 28
April 11
April 17
 

Parma

% Probability of Indicated Temperature or Lower on or After Date

 
90%
75%
50%
25%
10%
36 F
May 3
May 10
May 16
May 31
June 8
32 F
April 16
April 24
May 2
May 12
May 15
28 F
March 28
April 7
April 14
April 20
May 3
24 F
March 3
March 19
March 28
April 9
April 11
 

Nyssa

% Probability of Indicated Temperature or Lower on or After Date

 
90%
75%
50%
25%
10%
36 F
April 21
May 4
May 9
May 19
June 12
32 F
April 1
April 13
April 22
May 2
May 11
28 F
March 14
March 26
April 7
April 15
April 25
24 F
Feb. 17
March 2
March 16
April 7
April 10
 

Vale, Oregon

% Probability of Indicated Temperature or Lower on or After Date

 
90%
75%
50%
25%
10%
36 F
May 5
May 19
June 1
June 14
Jul 2
32 F
April 29
May 6
May 10
May 20
May 20
28 F
April 10
April 15
April 24
May 6
May 18
24 F
March 13
March 30
April 12
April 18
May 5
 

Grand View

% Probability of Indicated Temperature or Lower on or After Date

 
90%
75%
50%
25%
10%
36 F
May 1
May 7
May 16
May 25
June 6
32 F
April 17
April 27
May 5
May 12
May 16
28 F
April 6
April 9
April 15
April 27
May 7
24 F
March 3
March 24
March 31
April 12
April 17
 

Glenns Ferry

% Probability of Indicated Temperature or Lower on or After Date

 
90%
75%
50%
25%
10%
36 F
May 13
May 22
May 31
June 13
June 20
32 F
April 30
May 4
May 13
May 21
May 24
28 F
April 14
April 23
May 3
May 13
May 20
24 F
March 30
April 10
April 17
April 30
May 7
 

Twin Falls

% Probability of Indicated Temperature or Lower on or After Date

 
90%
75%
50%
25%
10%
36 F
May 19
May 24
June 5
June 12
June 19
32 F
April 30
May 6
May 10
May 19
May 25
28 F
April 15
April 26
May 1
May 7
May 13
24 F
March 18
March 30
April 11
April 27
May 3

Boise

% Probability of Temperature or Lower on or Before Date

 
10%
25%
50%
75%
90%
36 F
Sept. 10
Sept. 20
Sept. 25
Oct. 3
Oct. 10
32 F
Sept. 21
Sept. 30
Oct. 11
Oct. 20
Oct. 25
30 F
Oct. 6
Oct. 16
Oct. 25
Nov. 1
Nov. 8
28 F
Oct. 15
Oct. 29
Nov. 4
Nov. 19
Nov. 26
 

Nampa

% Probability of Temperature or Lower on or Before Date

 
10%
25%
50%
75%
90%
36 F
Sept. 10
Sept. 17
Sept.24
Oct. 6
Oct. 10
32 F
Sept. 25
Oct. 6
Oct. 11
Oct. 20
Oct. 25
28 F
Oct. 10
Oct. 13
Oct. 24
Oct. 30
Nov. 6
24 F
Oct. 18
Oct. 30
Nov. 8
Nov. 14
Nov. 21
 

Emmett

% Probability of Temperature or Lower on or Before Date

 
10%
25%
50%
75%
90%
36 F
Sept. 13
Sept. 21
Oct. 1
Oct. 7
Oct. 10
32 F
Sept. 22
Oct. 1
Oct. 13
Oct. 18
Oct. 30
28 F
Oct. 3
Oct. 12
Oct. 26
Oct. 31
Nov. 9
24 F
Oct. 19
Oct. 29
Nov. 3
Nov. 15
Nov. 23
 

Payette

% Probability of Temperature or Lower on or Before Date

 
10%
25%
50%
75%
90%
36 F
Sept. 11
Sept. 22
Sept. 30
Oct. 7
Oct. 12
32 F
Sept. 22
Sept. 28
Oct. 11
Oct. 17
Oct. 21
28 F
Oct. 3
Oct. 12
Oct. 21
Oct. 29
Nov. 2
24 F
Oct. 20
Oct. 25
Nov. 2
Nov. 10
Nov. 21
 

Parma

% Probability of Temperature or Lower on or Before Date

 
10%
25%
50%
75%
90%
36 F
Sept. 9
Sept. 13
Sept. 21
Sept. 30
Oct. 5
32 F
Sept. 19
Sept. 23
Oct. 4
Oct. 9
Oct. 12
28 F
Sept. 23
Oct. 8
Oct. 16
Oct. 21
Oct. 28
24 F
Oct. 8
Oct. 17
Oct. 30
Nov. 8
Nov. 21
 

Nyssa

% Probability of Temperature or Lower on or Before Date

 
10%
25%
50%
75%
90%
36 F
Sept. 18
Sept. 23
Oct. 1
Oct. 8
Oct. 14
32 F
Sept. 24
Oct. 4
Oct. 12
Oct. 23
Oct. 29
28 F
Oct. 11
Oct. 17
Oct. 25
Oct. 31
Nov. 11
24 F
Oct. 23
Oct. 30
Nov. 10
Nov. 21
Nov. 25
 

Vale, Oregon

% Probability of Temperature or Lower on or Before Date

 
10%
25%
50%
75%
90%
36 F
Sept. 2
Sept. 10
Sept. 16
Sept. 23
Oct. 4
32 F
Sept. 17
Sept. 21
Sept. 24
Oct. 1
Oct. 9
28 F
Sept. 22
Sept. 26
Oct. 10
Oct. 15
Oct. 26
24 F
Oct. 2
Oct. 12
Oct. 20
Oct. 31
Nov. 6
 

Grand View

% Probability of Temperature or Lower on or Before Date

 
10%
25%
50%
75%
90%
36 F
Sept. 7
Sept. 10
Sept. 19
Sept. 25
Oct. 4
32 F
Sept. 22
Sept. 24
Oct. 5
Oct. 10
Oct. 13
28 F
Sept. 26
Oct. 8
Oct. 14
Oct. 24
Oct 30
24 F
Oct. 13
Oct 18
Oct. 26
Nov. 2
Nov. 9
 

Glenns Ferry

% Probability of Temperature or Lower on or Before Date

 
10%
25%
50%
75%
90%
36 F
Aug. 27
Sept. 6
Sept. 10
Sept. 15
Sept. 23
32 F
Sept. 8
Sept. 15
Sept. 22
Oct. 4
Oct. 7
28 F
Sept. 21
Sept. 28
Oct. 10
Oct. 16
Oct. 21
24 F
Sept. 28
Oct. 14
Oct. 24
Nov. 2
Nov. 11
 

Twin Falls

% Probability of Temperature or Lower on or Before Date

 
10%
25%
50%
75%
90%
36 F
Aug. 30
Sept. 5
Sept. 13
Sept. 21
Sept. 22
32 F
Sept. 11
Sept. 17
Sept. 24
Oct. 5
Oct. 6
28 F
Sept. 23
Oct. 2
Oct. 10
Oct. 17
Oct. 25
24 F
Oct. 12
Oct. 17
Oct. 25
Nov. 1
Nov. 15

Jerome

% Probability of Indicated Temperature or Lower on or After Date

 
90%
75%
50%
25%
10%
36 F
May 10
May 18
May 27
June 9
June 13
32 F
April 30
May 4
May 10
May 20
June 2
28 F
April 8
April 15
April 27
May 3
May 7
24 F
March 16
March 25
April 4
April 13
April 20

Jerome

% Probability of Temperature or Lower on or Before Date

 
10%
25%
50%
75%
90%
36 F
Sept. 6
Sept. 14
Sept. 21
Oct. 2
Oct. 5
32 F
Sept. 21
Sept. 24
Oct. 5
Oct. 12
Oct. 20
28 F
Oct. 2
Oct. 8
Oct. 17
Oct. 27
Nov. 7
24 F
Oct. 12
Oct. 17
Oct. 30
Nov. 7
Nov. 15