When is the last frost in Idaho?

It varies by location. Across Idaho, average last spring frost dates range from April 6 (Culdesac) to June 22 (McCall). Look up your ZIP code for your local date.

Why do nearby towns have different frost dates?

Elevation, distance from large bodies of water, and whether a weather station sits in a valley, on a hill, or in a city all change how cold nights get. Each ZIP code is matched to the most representative nearby NOAA station.

Idaho frost dates

Average last spring and first fall frost (32°F) dates for 266 cities and towns in Idaho, from NOAA 1991-2020 climate normals. Average last frost dates range from April 6 in Culdesac to June 22 in McCall. Open a ZIP code for frost risk by date and a planting calendar.

Cities with several ZIP codes use the first-listed ZIP. Open a ZIP for exact local dates.
City	Avg last frost	Avg first frost	Season	ZIP codes
Aberdeen	May 21	Sep 20	118 days	83210
Ahsahka	May 16	Sep 23	128 days	83520
Albion	Jun 5	Sep 13	96 days	83311
Almo	Jun 4	Sep 17	104 days	83312
American Falls	May 20	Sep 26	125 days	83211
Arbon	May 23	Sep 24	121 days	83212
Arco	May 22	Sep 22	119 days	83213
Arimo	May 23	Sep 24	121 days	83214
Ashton	May 21	Sep 21	121 days	83420
Athol	May 22	Sep 22	122 days	83801
Atlanta	Jun 16	Sep 6	80 days	83601
Atomic City	Jun 11	Sep 6	89 days	83215
Avery	May 12	Sep 30	138 days	83802
Bancroft	May 29	Sep 17	111 days	83217
Banks	Jun 1	Sep 10	102 days	83602
Basalt	May 5	Oct 3	149 days	83218
Bayview	May 22	Sep 22	122 days	83803
Bellevue	May 13	Oct 2	139 days	83313
Bern	Jun 17	Sep 3	77 days	83220
Blackfoot	May 5	Oct 3	149 days	83221
Blanchard	May 12	Sep 21	130 days	83804
Bliss	May 3	Oct 1	151 days	83314
Bloomington	May 19	Sep 21	123 days	83223
Boise	Apr 24	Oct 21	179 days	83701, 83702, 83703, 83704 +24 more
Bonners Ferry	Apr 30	Oct 4	154 days	83805
Bovill	May 16	Sep 23	128 days	83806
Bruneau	May 17	Sep 29	132 days	83604
Buhl	Apr 25	Oct 15	172 days	83316
Burley	May 7	Oct 4	150 days	83318
Calder	May 12	Sep 30	138 days	83808
Caldwell	Apr 29	Oct 13	164 days	83605, 83606, 83607
Cambridge	May 15	Sep 27	134 days	83610
Carey	Jun 16	Sep 9	85 days	83320
Careywood	May 22	Sep 22	122 days	83809
Carmen	May 17	Sep 24	127 days	83462
Cascade	Any month	—	32 days	83611
Castleford	May 17	Sep 29	132 days	83321
Cataldo	May 3	Oct 4	152 days	83810
Challis	May 14	Sep 25	131 days	83226
Chester	May 21	Sep 21	121 days	83421
Clark Fork	May 9	Oct 8	153 days	83811
Clarkia	May 16	Sep 23	128 days	83812
Clayton	Any month	—	13 days	83227
Clifton	May 16	Sep 28	133 days	83228
Cobalt	May 14	Sep 25	131 days	83229
Cocolalla	May 20	Sep 13	114 days	83813
Coeur d'Alene	Apr 22	Oct 18	179 days	83814, 83815, 83816
Colburn	May 20	Sep 13	114 days	83865
Conda	Any month	—	69 days	83230
Coolin	May 20	Sep 13	114 days	83821
Corral	Any month	—	77 days	83322
Cottonwood	May 6	Oct 13	156 days	83522
Council	May 10	Oct 2	145 days	83612
Craigmont	May 23	Sep 25	121 days	83523
Culdesac	Apr 6	Oct 26	200 days	83524
Dayton	May 16	Sep 28	133 days	83232
Deary	May 16	Sep 23	128 days	83823
Declo	Jun 5	Sep 13	96 days	83323
Desmet	May 15	Sep 21	126 days	83824
Dietrich	Apr 24	Oct 16	173 days	83324
Dingle	May 19	Sep 21	123 days	83233
Donnelly	May 30	Sep 19	110 days	83615
Dover	May 8	Sep 28	141 days	83825
Downey	May 31	Sep 18	110 days	83234
Driggs	Jun 13	Sep 9	86 days	83422
Dubois	May 18	Sep 30	132 days	83423
Eagle	Apr 29	Oct 13	164 days	83616
Eastport	Apr 30	Oct 4	154 days	83826
Eden	May 7	Oct 5	149 days	83325
Elk City	Any month	—	64 days	83525
Elk River	May 16	Sep 23	128 days	83827
Ellis	Jun 12	Sep 6	85 days	83235
Emmett	Apr 30	Oct 17	168 days	83617
Fairfield	Jun 8	Sep 14	97 days	83327
Felt	Jun 15	Sep 7	85 days	83424
Fenn	May 9	Oct 3	146 days	83531
Ferdinand	May 6	Oct 13	156 days	83526
Fernwood	May 15	Sep 21	126 days	83830
Filer	Apr 25	Oct 15	172 days	83328
Firth	May 5	Oct 3	149 days	83236
Fish Haven	May 15	Oct 4	140 days	83287
Fort Hall	May 20	Sep 20	119 days	83203
Franklin	May 16	Sep 28	133 days	83237
Fruitland	Apr 21	Oct 14	176 days	83619
Garden City	Apr 24	Oct 21	179 days	83714
Garden Valley	Jun 17	Sep 5	80 days	83622
Genesee	Any month	—	85 days	83832
Geneva	Jun 17	Sep 3	77 days	83238
Georgetown	Jun 17	Sep 3	77 days	83239
Gibbonsville	Any month	—	22 days	83463
Glenns Ferry	May 1	Oct 3	154 days	83623
Gooding	May 2	Oct 14	166 days	83330
Grace	May 29	Sep 17	111 days	83241
Grand View	Apr 28	Oct 6	162 days	83624
Grangeville	May 9	Oct 3	146 days	83530
Greencreek	May 24	Sep 20	116 days	83533
Greenleaf	Apr 23	Oct 18	178 days	83626
Hagerman	May 3	Oct 1	151 days	83332
Hailey	May 13	Oct 2	139 days	83333
Hamer	Jun 3	Sep 11	98 days	83425
Hammett	May 1	Oct 3	154 days	83627
Hansen	May 6	Oct 3	150 days	83334
Harrison	Apr 22	Oct 18	179 days	83833
Harvard	May 15	Sep 21	126 days	83834
Hayden	Apr 22	Oct 18	179 days	83835
Hazelton	May 7	Oct 5	149 days	83335
Heyburn	May 7	Oct 4	150 days	83336
Hill City	Jun 16	Sep 6	80 days	83337
Holbrook	May 22	Sep 20	116 days	83243
Homedale	Apr 24	Oct 9	169 days	83628
Hope	May 8	Sep 28	141 days	83836
Horseshoe Bend	Apr 30	Oct 17	168 days	83629
Howe	May 24	Sep 14	113 days	83244
Huston	Apr 23	Oct 18	178 days	83630
Idaho City	Jun 17	Sep 5	80 days	83631
Idaho Falls	May 9	Oct 1	142 days	83401, 83402, 83403, 83404 +3 more
Indian Valley	May 15	Sep 27	134 days	83632
Inkom	May 23	Sep 24	121 days	83245
Iona	May 9	Oct 1	142 days	83427
Irwin	Any month	—	69 days	83428
Island Park	Any month	—	49 days	83429
Jerome	May 2	Oct 14	166 days	83338
Juliaetta	Apr 6	Oct 26	200 days	83535
Kamiah	Apr 29	Oct 5	163 days	83536
Kellogg	May 14	Sep 26	131 days	83837
Kendrick	Apr 20	Oct 20	182 days	83537
Ketchum	Any month	—	77 days	83340
Kimberly	May 6	Oct 3	150 days	83341
King Hill	May 1	Oct 3	154 days	83633
Kingston	May 14	Sep 26	131 days	83839
Kooskia	Apr 16	Oct 25	191 days	83539
Kootenai	May 8	Sep 28	141 days	83840
Kuna	Apr 24	Oct 21	179 days	83634
Laclede	May 8	Sep 28	141 days	83841
Lake Fork	Jun 10	Sep 10	93 days	83635
Lapwai	Apr 6	Oct 26	200 days	83540
Lava Hot Springs	May 21	Sep 21	118 days	83246
Leadore	Any month	—	50 days	83464
Lemhi	Jun 12	Sep 6	85 days	83465
Lenore	Any month	—	85 days	83541
Letha	Apr 30	Oct 17	168 days	83636
Lewiston	Apr 6	Oct 26	200 days	83501
Lewisville	May 9	Oct 1	142 days	83431
Lowman	Any month	—	13 days	83637
Lucile	May 9	Oct 3	146 days	83542
Mackay	Jun 1	Sep 20	109 days	83251
Macks Inn	Any month	—	66 days	83433
Malad City	May 22	Sep 20	116 days	83252
Malta	Jun 5	Sep 13	96 days	83342
Marsing	Apr 24	Oct 9	169 days	83639
May	Jun 12	Sep 6	85 days	83253
McCall	Jun 22	Sep 2	72 days	83638
McCammon	May 23	Sep 24	121 days	83250
Medimont	May 3	Oct 4	152 days	83842
Melba	Apr 29	Oct 13	164 days	83641
Menan	May 15	Sep 23	129 days	83434
Meridian	Apr 29	Oct 13	164 days	83642, 83646, 83680
Mesa	May 10	Oct 2	145 days	83643
Middleton	Apr 29	Oct 13	164 days	83644
Midvale	May 15	Sep 27	134 days	83645
Minidoka	May 16	Oct 1	136 days	83343
Monteview	Jun 12	Sep 7	87 days	83435
Montpelier	Jun 17	Sep 3	77 days	83254
Moore	Jun 14	Sep 8	86 days	83255
Moreland	May 5	Oct 3	149 days	83256
Moscow	Any month	—	85 days	83843, 83844
Mountain Home	May 2	Oct 8	157 days	83647
Mountain Home Afb	Apr 30	Oct 17	168 days	83648
Moyie Springs	Apr 30	Oct 4	154 days	83845
Mullan	May 12	Sep 30	138 days	83846
Murphy	May 31	Oct 6	128 days	83650
Murray	May 5	Oct 2	149 days	83874
Murtaugh	May 7	Oct 5	149 days	83344
Nampa	Apr 29	Oct 13	164 days	83651, 83652, 83653, 83686 +1 more
Naples	Apr 30	Oct 4	154 days	83847
New Meadows	Any month	—	62 days	83654
New Plymouth	Apr 23	Oct 13	173 days	83655
Newdale	May 17	Sep 22	126 days	83436
Nezperce	May 24	Sep 20	116 days	83543
Nordman	May 20	Sep 13	114 days	83848
North Fork	Any month	—	22 days	83466
Notus	Apr 27	Oct 9	165 days	83656
Oakley	May 15	Oct 2	137 days	83346
Ola	May 31	Sep 16	108 days	83657
Oldtown	May 12	Sep 21	130 days	83822
Orofino	May 16	Sep 23	128 days	83544
Osburn	May 5	Oct 2	149 days	83849
Paris	Jun 17	Sep 3	77 days	83261
Parker	May 17	Sep 22	126 days	83438
Parma	Apr 27	Oct 9	165 days	83660
Paul	May 6	Oct 6	151 days	83347
Payette	Apr 19	Oct 20	183 days	83661
Peck	Apr 20	Oct 20	182 days	83545
Picabo	Jun 16	Sep 9	85 days	83348
Pierce	Jun 3	Sep 7	93 days	83546
Pinehurst	May 12	Sep 30	138 days	83850
Pingree	May 20	Sep 20	119 days	83262
Placerville	Jun 17	Sep 5	80 days	83666
Plummer	May 11	Oct 5	143 days	83851
Pocatello	May 2	Oct 11	161 days	83201, 83202, 83204, 83205 +2 more
Pollock	May 6	Oct 9	155 days	83547
Ponderay	May 8	Sep 28	141 days	83852
Porthill	May 4	Sep 30	145 days	83853
Post Falls	Apr 22	Oct 18	179 days	83854, 83877
Potlatch	May 15	Sep 21	126 days	83855
Preston	May 16	Sep 28	133 days	83263
Priest River	May 12	Sep 21	130 days	83856
Princeton	May 15	Sep 21	126 days	83857
Rathdrum	Apr 22	Oct 18	179 days	83858
Reubens	May 24	Sep 20	116 days	83548
Rexburg	May 12	Sep 24	132 days	83440, 83441, 83460
Richfield	May 24	Sep 26	123 days	83349
Rigby	May 9	Oct 5	148 days	83442
Riggins	Any month	—	62 days	83549
Ririe	Jun 9	Sep 11	93 days	83443
Roberts	May 23	Sep 20	114 days	83444
Rockland	May 20	Sep 26	125 days	83271
Rogerson	Any month	—	83 days	83302
Rupert	May 16	Oct 1	136 days	83350
Sagle	May 8	Sep 28	141 days	83860
Saint Anthony	May 17	Sep 22	126 days	83445
Saint Charles	May 19	Sep 21	123 days	83272
Saint Maries	May 3	Oct 4	152 days	83861
Salmon	May 17	Sep 24	127 days	83467
Sandpoint	May 8	Sep 28	141 days	83864
Santa	May 15	Sep 21	126 days	83866
Shelley	May 23	Sep 20	114 days	83274
Shoshone	Apr 24	Oct 16	173 days	83352
Shoup	May 3	Oct 8	157 days	83469
Silverton	May 5	Oct 2	149 days	83867
Smelterville	May 14	Sep 26	131 days	83868
Soda Springs	Any month	—	69 days	83276
Spencer	May 18	Sep 30	132 days	83446
Spirit Lake	May 22	Sep 22	122 days	83869
Springfield	May 21	Sep 20	118 days	83277
Stanley	Any month	—	29 days	83278
Star	Apr 29	Oct 13	164 days	83669
Stites	Apr 30	Oct 11	162 days	83552
Sugar City	May 15	Sep 23	129 days	83448
Sun Valley	Any month	—	77 days	83353, 83354
Swan Valley	Any month	—	69 days	83449
Swanlake	May 29	Sep 17	111 days	83281
Sweet	Apr 30	Oct 17	168 days	83670
Tendoy	Any month	—	51 days	83468
Tensed	May 15	Sep 21	126 days	83870
Terreton	Jun 3	Sep 11	98 days	83450
Teton	May 17	Sep 22	126 days	83451
Tetonia	Jun 13	Sep 9	86 days	83452
Thatcher	May 29	Sep 17	111 days	83283
Troy	Any month	—	85 days	83871
Twin Falls	Apr 30	Oct 9	161 days	83301, 83303
Ucon	May 9	Oct 1	142 days	83454
Victor	Jun 13	Sep 9	86 days	83455
Viola	May 15	Sep 21	126 days	83872
Wallace	May 5	Oct 2	149 days	83873
Warren	Any month	—	23 days	83671
Wayan	Any month	—	67 days	83285
Weippe	Jun 3	Sep 7	93 days	83553
Weiser	Apr 23	Oct 13	174 days	83672
Wendell	May 2	Oct 14	166 days	83355
Weston	May 16	Sep 28	133 days	83286
White Bird	May 6	Oct 9	155 days	83554
Wilder	Apr 24	Oct 9	169 days	83676
Winchester	May 23	Sep 25	121 days	83555
Worley	May 11	Oct 5	143 days	83876
Yellow Pine	Jun 12	Sep 11	88 days	83677

Frequently asked questions

When is the last frost in Idaho?: It varies by location. Across Idaho, average last spring frost dates range from April 6 (Culdesac) to June 22 (McCall). Look up your ZIP code for your local date.
Why do nearby towns have different frost dates?: Elevation, distance from large bodies of water, and whether a weather station sits in a valley, on a hill, or in a city all change how cold nights get. Each ZIP code is matched to the most representative nearby NOAA station.