Atmospheric River in the Pacific Northwest and Northern Rockies this Weekend

A Pacific storm and atmospheric river will impact the Pacific Northwest states and northern Rockies this weekend, bringing locally heavy low elevations rain and heavy high elevation snow in the mountains. By Sunday over the Interior Northwest, rain combined with snowmelt will increase the risk of flood hazards. Flood Watches are in effect. Read More >

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

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