Alaska Frost Dates: Last and First Frost by Town

192 NOAA weather stations · 1991–2020 U.S. Climate Normals · Data updated 2026-10-29

Quick answer

Across Alaska's 163 NOAA stations with regular frost, the median last spring frost is May 16 and the median first fall frost is September 22. Last frost dates range from April 4 at Annette Island Airport to June 12 at Cooper Landing 5 W, so enter your ZIP code below for the station nearest you.

How frost dates vary across Alaska

Elevation matters: across Alaska's stations, each 1,000 ft of elevation delays the median last frost by about 11 days.
North vs south: stations in the northern third of the state (north of 62.0°N) reach their median last frost about 21 days later than the southern third (south of 59.6°N).
Safety margin: the median 10%-risk date (May 30) is about 14 days after the median last frost. Waiting until then cuts the chance of a killing frost on tender transplants from 1 in 2 to 1 in 10.

Frost dates at Alaska's major weather stations

These National Weather Service stations, mostly at airports, have the longest and most complete records in the state.


Anchorage Intl Airport	120	May 5	May 15	Oct 1	147
Anchorage Lake Hood Airport	90	May 1	May 8	Oct 3	156
Anchorage Merrill Field	138	May 1	May 9	Sep 29	150
Annette Island Airport	109	Apr 4	Apr 22	Oct 31	208
Barrow Post Rogers Airport	31	Any month	Any month	Any month	26
Bethel Airport	102	May 21	Jun 2	Sep 22	122
Bettles Airport	642	May 22	Jun 5	Aug 24	94
Big Delta Airport	1,277	May 17	May 31	Sep 7	113
Cold Bay Airport	78	May 25	Jun 10	Oct 4	131
Cordova M K Smith Airport	31	May 23	Jun 5	Sep 19	118
Deadhorse Airport	61	Any month	Any month	Any month	47
Deering Airport	21	Any month	Any month	Any month	76
Denali 27 N	2,225	May 25	Jun 3	Sep 8	105
Eagle Airport	908	Any month	Any month	Any month	61
Fairbanks 11 NE	1,140	May 12	May 29	Sep 16	124
Fairbanks Intl Airport	432	May 13	May 26	Sep 13	121
Glennallen 64 N	2,669	Jun 5	Jun 21	Aug 24	76
Gulkana Airport	1,562	Jun 7	Jul 5	Aug 21	73
Gustavus	40	May 30	Jun 22	Sep 16	107
Gustavus 2 NE	20	May 28	Jun 12	Sep 25	116
Haines Airport	15	Apr 25	May 7	Oct 12	172
Homer Airport	64	May 10	May 23	Sep 29	141
Iliamna Airport	143	May 10	May 25	Oct 1	144
Juneau Intl Airport	16	May 4	May 18	Oct 3	150
Kaltag Airport	181	May 25	Jun 11	Sep 3	101
Kenai 29 ENE	282	Jun 1	Jun 18	Sep 8	94
Kenai Municipal Airport	91	May 24	Jun 4	Sep 12	110
Ketchikan Intl Airport	76	Apr 22	May 9	Oct 23	185
King Salmon	63	May 26	Jun 11	Sep 15	111
King Salmon 42 SE	661	Jun 9	Jun 22	Sep 11	93
Kivalina Airport	10	Jun 10	Jun 23	Sep 11	92
Klawock Airport	12	Apr 29	May 14	Oct 16	169
Kodiak Airport	80	May 5	May 21	Oct 3	151
Kotzebue Ralph Wein Airport	30	Jun 5	Jun 17	Sep 24	110
McGrath Airport	333	May 13	May 28	Sep 13	120
Metlakatla 6 S	105	Apr 14	May 1	Oct 25	192
Nenana Municipal Airport	360	May 15	May 29	Sep 11	117
Nome Municipal Airport	13	Jun 5	Jun 26	Sep 3	88
Northway Airport	1,713	May 26	Jun 8	Sep 1	97
Nuiqsut Airport	57	Any month	Any month	Any month	51
Palmer Municipal Airport	230	May 6	May 18	Sep 25	140
Petersburg 1	107	Apr 29	May 14	Oct 17	169
Port Alsworth 1 SW	321	Jun 2	Jun 13	Sep 12	101
Portage Glacier V C	103	May 27	Jun 11	Sep 12	106
Ruby 44 ESE	259	May 22	Jun 3	Sep 3	101
Sand Point 1 ENE	240	May 11	May 25	Oct 18	160
Seldovia Airport	29	May 10	May 24	Oct 1	145
Seward Airport	22	May 2	May 17	Oct 7	158
Sitka 1 NE	78	May 3	May 19	Oct 18	166
Sitka Airport	14	Apr 12	Apr 30	Nov 1	201
Skagway Airport	20	Apr 21	May 2	Oct 17	176
Skwentna	150	May 23	Jun 4	Sep 9	109
St George Island Airport	125	May 31	Jun 23	Oct 5	128
St Paul Island Airport	35	Jun 4	Jun 25	Sep 28	114
St. Paul 4 NE	20	Jun 5	Jul 1	Sep 28	110
Talkeetna Airport	350	May 16	May 28	Sep 16	122
Tanana Calhoun Memorial Airport	227	May 29	Jun 16	Aug 28	89
Tok 70 SE	2,000	Any month	Any month	Any month	53
Toolik Lake 5 ENE	2,461	Any month	Any month	Any month	47
Utqiagvik Formerly Barrow 4 En	15	Any month	Any month	Any month	21
Valdez WSO	95	Apr 30	May 10	Oct 2	157
Wainwright Airport	30	Any month	Any month	Any month	43
Yakutat 3 SSE	26	May 13	May 29	Sep 26	133
Yakutat State Airport	33	May 20	May 31	Sep 23	124

All 192 stations in Alaska

Last frost and first frost are medians: a 50% chance of a 32°F night after (spring) or before (fall) that date. 10% risk is the spring date with only a 1-in-10 chance of a later frost. Click a column to sort.

Filter by station name


Alpine	17	Any month	Any month	Any month	53
Alyeska	272	May 8	May 22	Sep 29	142
Amber Lake	449	May 28	Jun 9	Sep 13	107
Anchorage Forecast Office	131	May 5	May 14	Sep 29	147
Anchorage Intl Airport	120	May 5	May 15	Oct 1	147
Anchorage Lake Hood Airport	90	May 1	May 8	Oct 3	156
Anchorage Merrill Field	138	May 1	May 9	Sep 29	150
Anchorage Rabbit Creek #2	913	May 12	May 24	Sep 26	137
Anchorage Upper De Armoun	1,335	May 7	May 23	Sep 28	143
Anderson Lake	458	May 16	May 31	Sep 23	128
Annette Island Airport	109	Apr 4	Apr 22	Oct 31	208
Annex Creek	92	May 3	May 18	Oct 14	164
Auke Bay	44	Apr 27	May 11	Oct 18	172
Aurora	443	May 16	May 29	Sep 6	112
Barrow Post Rogers Airport	31	Any month	Any month	Any month	26
Beaver Falls	35	Apr 4	Apr 25	Nov 9	218
Ben's Farm	127	May 12	May 24	Sep 20	129
Bethel Airport	102	May 21	Jun 2	Sep 22	122
Bettles Airport	642	May 22	Jun 5	Aug 24	94
Big Delta Airport	1,277	May 17	May 31	Sep 7	113
Big River Lakes	60	May 7	May 25	Oct 7	151
Campbell Creek Science Center	258	May 28	Jun 6	Sep 12	107
Cannery Creek	85	May 16	May 29	Oct 3	139
Cantwell 2 E	2,132	Any month	Any month	Any month	45
Central #2	920	May 25	Jun 6	Aug 26	92
Chandalar Lake	1,895	Any month	Any month	Any month	66
Chandalar Shelf Dot	3,250	Any month	Any month	Any month	69
Chicken	1,800	Any month	Any month	Any month	42
Chulitna River	1,354	Any month	Any month	Any month	49
Circle Hot Springs	860	Any month	Any month	Any month	58
Clear Sky	646	May 24	Jun 12	Sep 4	100
Cold Bay Airport	78	May 25	Jun 10	Oct 4	131
College 5 NW	978	May 13	May 31	Sep 15	122
College Obsy	597	May 18	Jun 1	Sep 6	111
Colville Village	5	Any month	Any month	Any month	48
Cooper Lake Project	505	May 18	May 31	Sep 27	130
Cooper Landing 5 W	375	Jun 12	Jul 2	Sep 1	78
Cordova M K Smith Airport	31	May 23	Jun 5	Sep 19	118
Cordova N	25	Apr 24	May 8	Oct 19	176
Cordova Wwtp	10	Apr 29	May 13	Oct 13	169
Craig	43	Apr 14	May 2	Nov 1	201
Deadhorse Airport	61	Any month	Any month	Any month	47
Deering Airport	21	Any month	Any month	Any month	76
Delta 5 NE	1,060	Jun 4	Jul 17	Aug 22	75
Delta 6 N	1,059	Any month	Any month	Any month	63
Delta Junction 20 SE	1,125	Jun 5	Jun 30	Aug 21	75
Denali 27 N	2,225	May 25	Jun 3	Sep 8	105
Dry Creek	1,355	May 30	Jun 13	Aug 24	84
Dutch Harbor	10	May 6	May 22	Oct 18	164
Eagle	850	May 29	Jun 11	Aug 23	86
Eagle Airport	908	Any month	Any month	Any month	61
Eagle River 5 SE	498	May 21	Jun 3	Sep 15	116
Eagle River Gakona Circle	567	May 9	May 22	Sep 26	139
Eagle River Nature Center	520	May 16	Jun 9	Sep 20	125
Eaglecrest Base	1,134	May 21	Jun 2	Oct 1	132
Eielson Field	547	May 20	Jun 3	Sep 1	104
Eklutna Wtp	640	May 18	May 30	Sep 20	124
Elfin Cove	20	Apr 26	May 8	Nov 1	188
Ester	655	May 24	Jun 4	Sep 1	98
Ester 5NE	630	Any month	Any month	Any month	65
Fairbanks 11 NE	1,140	May 12	May 29	Sep 16	124
Fairbanks Airport #2	427	May 16	May 30	Sep 8	113
Fairbanks Intl Airport	432	May 13	May 26	Sep 13	121
Fairbanks Midtown	440	May 13	May 28	Sep 10	119
Farewell Lake	1,060	May 30	Jun 15	Sep 5	97
Fort Knox Mine	1,621	May 12	May 28	Sep 17	126
Fort Richardson Wtp	470	May 9	May 22	Sep 26	138
Fox 2 SE	775	May 28	Jun 9	Sep 1	96
Galena	152	May 18	Jun 1	Sep 8	111
Gennallen Kcam	1,383	Any month	Any month	Any month	61
Gilmore Creek	945	Jun 1	Jun 17	Aug 28	87
Glacier Bay	45	May 6	May 26	Oct 10	154
Glen Alps	2,202	May 18	May 31	Sep 23	125
Glennallen 64 N	2,669	Jun 5	Jun 21	Aug 24	76
Goldstream Creek	577	Any month	Any month	Any month	75
Gulkana Airport	1,562	Jun 7	Jul 5	Aug 21	73
Gustavus	40	May 30	Jun 22	Sep 16	107
Gustavus 2 NE	20	May 28	Jun 12	Sep 25	116
Haines #2	95	Apr 30	May 13	Oct 7	160
Haines 40NW	820	May 24	Jun 10	Sep 20	118
Haines Airport	15	Apr 25	May 7	Oct 12	172
Hayes River	1,000	Jun 2	Jun 11	Sep 8	98
Healy	1,417	May 27	Jun 10	Sep 1	97
Hidden Falls Hatchery	22	Apr 29	May 15	Oct 25	176
Homer 8 NW	1,080	May 16	May 30	Sep 30	136
Homer 9 E	512	May 27	Jun 8	Sep 22	116
Homer Airport	64	May 10	May 23	Sep 29	141
Hoonah	130	May 9	Jul 4	Oct 4	145
Hope	180	May 18	May 28	Sep 24	127
Hyder	80	May 4	May 23	Oct 11	157
Iliamna Airport	143	May 10	May 25	Oct 1	144
Intricate Bay	120	Jun 4	Jun 22	Sep 12	98
Juneau Dwtn	50	Apr 20	May 5	Oct 22	183
Juneau Forecast Office	106	May 9	May 24	Oct 4	146
Juneau Intl Airport	16	May 4	May 18	Oct 3	150
Juneau Lena Point	35	Apr 11	Apr 27	Nov 1	202
Juneau Mile 17	245	Apr 29	May 10	Oct 20	173
Kaltag Airport	181	May 25	Jun 11	Sep 3	101
Kenai 29 ENE	282	Jun 1	Jun 18	Sep 8	94
Kenai 9N	126	May 18	May 30	Sep 22	125
Kenai Municipal Airport	91	May 24	Jun 4	Sep 12	110
Ketchikan 10N	295	Apr 20	May 4	Oct 26	189
Ketchikan Intl Airport	76	Apr 22	May 9	Oct 23	185
Keystone Ridge	1,600	May 15	May 31	Sep 16	122
King Salmon	63	May 26	Jun 11	Sep 15	111
King Salmon 42 SE	661	Jun 9	Jun 22	Sep 11	93
Kitoi Bay	60	May 11	May 28	Oct 6	149
Kivalina Airport	10	Jun 10	Jun 23	Sep 11	92
Klawock Airport	12	Apr 29	May 14	Oct 16	169
Kobe Hill	800	May 24	Jun 10	Sep 2	100
Kodiak Airport	80	May 5	May 21	Oct 3	151
Kodiak Wwtp	54	Apr 29	May 13	Oct 14	168
Kotzebue Ralph Wein Airport	30	Jun 5	Jun 17	Sep 24	110
Kuparuk	64	Any month	Any month	Any month	38
Lake Susitna	2,375	May 30	Jun 9	Sep 4	95
Lazy Mountain	733	May 22	Jun 3	Sep 16	114
Little Port Walter	14	Apr 21	May 9	Oct 31	190
Little Su At Hatcher Pass Brg	902	May 18	May 30	Sep 18	122
Main Bay	57	May 19	Jun 4	Oct 6	139
Manley Hot Springs 15NE	501	Any month	Any month	Any month	80
Matanuska Experiment Farm	172	May 14	May 26	Sep 20	127
McCarthy 3 SW	1,250	Any month	Any month	Any month	63
McGrath Airport	333	May 13	May 28	Sep 13	120
McKinley Park	2,070	Jun 6	Jun 30	Aug 25	77
Metlakatla 6 S	105	Apr 14	May 1	Oct 25	192
Mile 42 Steese	960	May 28	Jun 19	Aug 26	87
Minchumina	1,025	May 13	May 28	Sep 17	124
Monashka Creek Dam	130	May 27	Jun 10	Sep 23	117
Moose Pass 3NW	492	May 31	Jun 15	Sep 8	99
N Pole	475	May 18	May 31	Sep 5	110
N Pole 1N	496	May 22	Jun 4	Sep 2	102
Nabesna	2,920	Jun 4	Jul 3	Sep 1	85
Nenana Municipal Airport	360	May 15	May 29	Sep 11	117
Nome Municipal Airport	13	Jun 5	Jun 26	Sep 3	88
Northway Airport	1,713	May 26	Jun 8	Sep 1	97
Nuiqsut Airport	57	Any month	Any month	Any month	51
Ouzinkie	40	May 9	May 23	Oct 4	148
Palmer Job Corps	216	Apr 24	May 9	Oct 4	164
Palmer Municipal Airport	230	May 6	May 18	Sep 25	140
Paxson	2,700	Any month	Any month	Any month	60
Pelican	12	May 4	May 18	Oct 19	167
Petersburg 1	107	Apr 29	May 14	Oct 17	169
Point Baker	20	Apr 19	May 5	Oct 25	187
Port Alcan	1,892	May 28	Jun 10	Aug 29	91
Port Alexander	12	Apr 18	May 5	Nov 5	198
Port Alsworth	260	May 12	May 27	Sep 24	134
Port Alsworth 1 SW	321	Jun 2	Jun 13	Sep 12	101
Port San Juan	40	May 10	May 28	Oct 7	150
Portage Glacier V C	103	May 27	Jun 11	Sep 12	106
Puntilla	1,858	Jun 7	Jun 30	Sep 2	83
Ruby 44 ESE	259	May 22	Jun 3	Sep 3	101
Sand Point 1 ENE	240	May 11	May 25	Oct 18	160
Seldovia Airport	29	May 10	May 24	Oct 1	145
Seward 19N	518	May 21	May 31	Sep 26	127
Seward 8 NW	424	Any month	Any month	Any month	67
Seward Airport	22	May 2	May 17	Oct 7	158
Silver Lake	1,200	May 31	Jun 10	Sep 3	95
Sitka 1 NE	78	May 3	May 19	Oct 18	166
Sitka Airport	14	Apr 12	Apr 30	Nov 1	201
Skagway	35	May 6	May 22	Oct 1	146
Skagway Airport	20	Apr 21	May 2	Oct 17	176
Skwentna	150	May 23	Jun 4	Sep 9	109
Snettisham Pwr Plt	29	May 5	May 22	Oct 15	162
Soldotna 5SSW	180	Jun 11	Jul 7	Sep 1	75
St George Island Airport	125	May 31	Jun 23	Oct 5	128
St Paul Island Airport	35	Jun 4	Jun 25	Sep 28	114
St. Paul 4 NE	20	Jun 5	Jul 1	Sep 28	110
Sterling 6SW	292	May 20	Jun 1	Sep 21	123
Sutton 1 W	550	Jun 1	Jun 13	Sep 6	98
Talkeetna Airport	350	May 16	May 28	Sep 16	122
Tanana Calhoun Memorial Airport	227	May 29	Jun 16	Aug 28	89
Thorne Bay	286	May 1	May 16	Oct 13	166
Tok	1,625	Any month	Any month	Any month	64
Tok #2	1,658	Jun 3	Jul 13	Aug 27	79
Tok 70 SE	2,000	Any month	Any month	Any month	53
Tonsina	1,579	Any month	Any month	Any month	72
Toolik Lake 5 ENE	2,461	Any month	Any month	Any month	47
Two Rivers	605	May 30	Jun 13	Sep 2	95
University Experiment Station	475	May 16	May 30	Sep 8	114
Utqiagvik Formerly Barrow 4 En	15	Any month	Any month	Any month	21
Valdez	62	May 14	May 26	Sep 22	129
Valdez WSO	95	Apr 30	May 10	Oct 2	157
Wainwright Airport	30	Any month	Any month	Any month	43
Wally Noerenberg Hatchery	35	May 20	Jun 1	Oct 9	142
Whites Crossing	270	May 29	Jun 9	Sep 7	100
Whitestone Farms	995	May 26	Jun 9	Sep 2	98
Whittier	60	Apr 25	May 8	Oct 14	172
Willow West	205	May 15	May 28	Sep 18	126
Wiseman	1,181	Any month	Any month	Any month	76
Wrangell Airport	56	Apr 11	Apr 29	Nov 1	202
Yakutat 3 SSE	26	May 13	May 29	Sep 26	133
Yakutat State Airport	33	May 20	May 31	Sep 23	124

Frequently asked questions

When is the last frost in Alaska?

The median last spring frost (32°F) across Alaska's NOAA weather stations is May 16, based on 1991–2020 climate normals. It ranges from April 4 at Annette Island Airport to June 12 at Cooper Landing 5 W. For a safer planting date, use the 10%-risk date; the state median for that is May 30.

When is the first frost in Alaska?

The median first fall frost across Alaska's stations is September 22. The earliest median first frost is August 21 at Delta Junction 20 SE, and the latest is November 9 at Beaver Falls.

How long is the growing season in Alaska?

The median frost-free season is 124 days across Alaska's stations, from 73 days at Gulkana Airport to 218 days at Beaver Falls.

When should I plant tomatoes in Alaska?

Plant tomatoes outdoors after your local last frost, ideally after the 10%-risk date when nights stay above 50°F. At a typical Alaska station that means starting seeds indoors 6–8 weeks before May 16 and transplanting from about May 30. Check your ZIP code, because dates vary by weeks across the state.

Can it frost in summer in Alaska?

Yes, at 29 stations in Alaska a 32°F night is possible in any month, mostly at high elevation or far north. There is no reliable frost-free season there; use cold-hardy crops and row covers.

How to use these dates

Frost dates are 30-year averages from NOAA, not forecasts. Use them to plan seed starting and planting, then watch the 10-day forecast as the date approaches. Cold air settles in valleys and low spots, so a garden at the bottom of a slope can frost a week or more later in spring than the nearest station shows.

Ready to plan? The planting calendar by ZIP code turns these dates into start-indoors, transplant and sowing dates for 30 crops.

Sources and method

Dates are the 32°F freeze probabilities published in the NOAA NCEI 1991–2020 U.S. Climate Normals for each station. Station names are NOAA's, lightly expanded for readability. See the methodology or download the full table.