Last frost dates in Alaska
163 NOAA weather stations in Alaska have thirty years of frost records. The median station sees its last 32 °F night around May 16; across the state that ranges from Apr 4 to Jun 12, so pick the station nearest you rather than a state-wide figure.
| ANNETTE ISLAND AP | Apr 4 | Apr 22 | Mar 20 | Oct 31 | 208 |
| BEAVER FALLS | Apr 4 | Apr 25 | Mar 15 | Nov 9 | 218 |
| JUNEAU LENA PT | Apr 11 | Apr 27 | Mar 27 | Nov 1 | 202 |
| WRANGELL AP | Apr 11 | Apr 29 | Mar 26 | Nov 1 | 202 |
| SITKA AIRPORT | Apr 12 | Apr 30 | Mar 28 | Nov 1 | 201 |
| CRAIG | Apr 14 | May 2 | Mar 30 | Nov 1 | 201 |
| METLAKATLA 6 S | Apr 14 | May 1 | Mar 30 | Oct 25 | 192 |
| PORT ALEXANDER | Apr 18 | May 5 | Mar 31 | Nov 5 | 198 |
| PT BAKER | Apr 19 | May 5 | Apr 4 | Oct 25 | 187 |
| JUNEAU DWTN | Apr 20 | May 5 | Apr 5 | Oct 22 | 183 |
| KETCHIKAN 10N | Apr 20 | May 4 | Apr 1 | Oct 26 | 189 |
| LITTLE PORT WALTER | Apr 21 | May 9 | Mar 31 | Oct 31 | 190 |
| SKAGWAY AP | Apr 21 | May 2 | Apr 9 | Oct 17 | 176 |
| KETCHIKAN INTL AP | Apr 22 | May 9 | Apr 2 | Oct 23 | 185 |
| CORDOVA N | Apr 24 | May 8 | Apr 10 | Oct 19 | 176 |
| PALMER JOB CORPS | Apr 24 | May 9 | Apr 11 | Oct 4 | 164 |
| HAINES AP | Apr 25 | May 7 | Apr 10 | Oct 12 | 172 |
| WHITTIER | Apr 25 | May 8 | Apr 12 | Oct 14 | 172 |
| ELFIN COVE | Apr 26 | May 8 | Apr 8 | Nov 1 | 188 |
| AUKE BAY | Apr 27 | May 11 | Apr 12 | Oct 18 | 172 |
| CORDOVA WWTP | Apr 29 | May 13 | Apr 9 | Oct 13 | 169 |
| HIDDEN FALLS HATCHERY | Apr 29 | May 15 | Apr 15 | Oct 25 | 176 |
| JUNEAU MILE 17 | Apr 29 | May 10 | Apr 15 | Oct 20 | 173 |
| KLAWOCK AP | Apr 29 | May 14 | Apr 13 | Oct 16 | 169 |
| KODIAK WWTP | Apr 29 | May 13 | Apr 14 | Oct 14 | 168 |
| PETERSBURG 1 | Apr 29 | May 14 | Apr 15 | Oct 17 | 169 |
| HAINES #2 | Apr 30 | May 13 | Apr 16 | Oct 7 | 160 |
| VALDEZ WSO | Apr 30 | May 10 | Apr 17 | Oct 2 | 157 |
| ANCHORAGE LAKE HOOD AP | May 1 | May 8 | Apr 20 | Oct 3 | 156 |
| ANCHORAGE MERRILL FLD | May 1 | May 9 | Apr 19 | Sep 29 | 150 |
| THORNE BAY | May 1 | May 16 | Apr 17 | Oct 13 | 166 |
| SEWARD AP | May 2 | May 17 | Apr 20 | Oct 7 | 158 |
| ANNEX CREEK | May 3 | May 18 | Apr 18 | Oct 14 | 164 |
| SITKA 1 NE | May 3 | May 19 | Apr 16 | Oct 18 | 166 |
| HYDER | May 4 | May 23 | Apr 22 | Oct 11 | 157 |
| JUNEAU INTL AP | May 4 | May 18 | Apr 23 | Oct 3 | 150 |
| PELICAN | May 4 | May 18 | Apr 19 | Oct 19 | 167 |
| ANCHORAGE FORECAST OFFICE | May 5 | May 14 | Apr 25 | Sep 29 | 147 |
| ANCHORAGE INTL AP | May 5 | May 15 | Apr 24 | Oct 1 | 147 |
| KODIAK AP | May 5 | May 21 | Apr 19 | Oct 3 | 151 |
| SNETTISHAM PWR PLT | May 5 | May 22 | Apr 19 | Oct 15 | 162 |
| DUTCH HARBOR | May 6 | May 22 | Apr 23 | Oct 18 | 164 |
| GLACIER BAY | May 6 | May 26 | Apr 22 | Oct 10 | 154 |
| PALMER MUNI AP | May 6 | May 18 | Apr 24 | Sep 25 | 140 |
| SKAGWAY | May 6 | May 22 | Apr 24 | Oct 1 | 146 |
| ANCHORAGE UPPER DE ARMOUN | May 7 | May 23 | Apr 23 | Sep 28 | 143 |
| BIG RIVER LAKES | May 7 | May 25 | Apr 21 | Oct 7 | 151 |
| ALYESKA | May 8 | May 22 | Apr 26 | Sep 29 | 142 |
| EAGLE RVR GAKONA CIRCLE | May 9 | May 22 | Apr 29 | Sep 26 | 139 |
| FT RICHARDSON WTP | May 9 | May 22 | Apr 28 | Sep 26 | 138 |
| HOONAH | May 9 | Jul 4 | Apr 25 | Oct 4 | 145 |
| JUNEAU FORECAST OFFICE | May 9 | May 24 | Apr 28 | Oct 4 | 146 |
| OUZINKIE | May 9 | May 23 | Apr 22 | Oct 4 | 148 |
| HOMER AP | May 10 | May 23 | Apr 27 | Sep 29 | 141 |
| ILIAMNA AP | May 10 | May 25 | Apr 28 | Oct 1 | 144 |
| PORT SAN JUAN | May 10 | May 28 | Apr 26 | Oct 7 | 150 |
| SELDOVIA AP | May 10 | May 24 | Apr 26 | Oct 1 | 145 |
| KITOI BAY | May 11 | May 28 | Apr 25 | Oct 6 | 149 |
| SAND POINT 1 ENE | May 11 | May 25 | Apr 26 | Oct 18 | 160 |
| ANCHORAGE RABBIT CREEK #2 | May 12 | May 24 | Apr 30 | Sep 26 | 137 |
| BEN'S FARM | May 12 | May 24 | May 1 | Sep 20 | 129 |
| FAIRBANKS 11 NE | May 12 | May 29 | May 2 | Sep 16 | 124 |
| FT KNOX MINE | May 12 | May 28 | May 1 | Sep 17 | 126 |
| PORT ALSWORTH | May 12 | May 27 | Apr 29 | Sep 24 | 134 |
| COLLEGE 5 NW | May 13 | May 31 | May 2 | Sep 15 | 122 |
| FAIRBANKS INTL AP | May 13 | May 26 | May 2 | Sep 13 | 121 |
| FAIRBANKS MIDTOWN | May 13 | May 28 | May 3 | Sep 10 | 119 |
| MCGRATH AP | May 13 | May 28 | May 4 | Sep 13 | 120 |
| MINCHUMINA | May 13 | May 28 | May 3 | Sep 17 | 124 |
| YAKUTAT 3 SSE | May 13 | May 29 | Apr 29 | Sep 26 | 133 |
| MATANUSKA EXP FARM | May 14 | May 26 | May 3 | Sep 20 | 127 |
| VALDEZ | May 14 | May 26 | May 2 | Sep 22 | 129 |
| KEYSTONE RIDGE | May 15 | May 31 | May 3 | Sep 16 | 122 |
| NENANA MUNI AP | May 15 | May 29 | May 3 | Sep 11 | 117 |
| WILLOW WEST | May 15 | May 28 | May 3 | Sep 18 | 126 |
| ANDERSON LAKE | May 16 | May 31 | May 1 | Sep 23 | 128 |
| AURORA | May 16 | May 29 | May 5 | Sep 6 | 112 |
| CANNERY CREEK | May 16 | May 29 | May 2 | Oct 3 | 139 |
| EAGLE RVR NATURE CTR | May 16 | Jun 9 | May 2 | Sep 20 | 125 |
| FAIRBANKS AP #2 | May 16 | May 30 | May 4 | Sep 8 | 113 |
| HOMER 8 NW | May 16 | May 30 | May 1 | Sep 30 | 136 |
| TALKEETNA AP | May 16 | May 28 | May 6 | Sep 16 | 122 |
| UNIVERSITY EXP STN | May 16 | May 30 | May 5 | Sep 8 | 114 |
| BIG DELTA AP | May 17 | May 31 | May 3 | Sep 7 | 113 |
| COLLEGE OBSY | May 18 | Jun 1 | May 7 | Sep 6 | 111 |
| COOPER LAKE PROJECT | May 18 | May 31 | May 6 | Sep 27 | 130 |
| EKLUTNA WTP | May 18 | May 30 | May 6 | Sep 20 | 124 |
| GALENA | May 18 | Jun 1 | May 8 | Sep 8 | 111 |
| GLEN ALPS | May 18 | May 31 | May 4 | Sep 23 | 125 |
| HOPE | May 18 | May 28 | May 8 | Sep 24 | 127 |
| KENAI 9N | May 18 | May 30 | May 5 | Sep 22 | 125 |
| LITTLE SU AT HATCHER PASS BRG | May 18 | May 30 | May 6 | Sep 18 | 122 |
| N POLE | May 18 | May 31 | May 6 | Sep 5 | 110 |
| MAIN BAY | May 19 | Jun 4 | May 2 | Oct 6 | 139 |
| EIELSON FLD | May 20 | Jun 3 | May 10 | Sep 1 | 104 |
| STERLING 6SW | May 20 | Jun 1 | May 6 | Sep 21 | 123 |
| WALLY NOERENBERG HATCHERY | May 20 | Jun 1 | May 5 | Oct 9 | 142 |
| YAKUTAT STATE AP | May 20 | May 31 | May 3 | Sep 23 | 124 |
| BETHEL AP | May 21 | Jun 2 | May 8 | Sep 22 | 122 |
| EAGLE RVR 5 SE | May 21 | Jun 3 | May 8 | Sep 15 | 116 |
| EAGLECREST BASE | May 21 | Jun 2 | May 5 | Oct 1 | 132 |
| SEWARD 19N | May 21 | May 31 | May 9 | Sep 26 | 127 |
| BETTLES AP | May 22 | Jun 5 | May 11 | Aug 24 | 94 |
| LAZY MTN | May 22 | Jun 3 | May 9 | Sep 16 | 114 |
| N POLE 1N | May 22 | Jun 4 | May 12 | Sep 2 | 102 |
| RUBY 44 ESE | May 22 | Jun 3 | May 12 | Sep 3 | 101 |
| CORDOVA M K SMITH AP | May 23 | Jun 5 | May 7 | Sep 19 | 118 |
| SKWENTNA | May 23 | Jun 4 | May 8 | Sep 9 | 109 |
| CLEAR SKY | May 24 | Jun 12 | May 11 | Sep 4 | 100 |
| ESTER | May 24 | Jun 4 | May 12 | Sep 1 | 98 |
| HAINES 40NW | May 24 | Jun 10 | May 10 | Sep 20 | 118 |
| KENAI MUNI AP | May 24 | Jun 4 | May 8 | Sep 12 | 110 |
| KOBE HILL | May 24 | Jun 10 | May 9 | Sep 2 | 100 |
| CENTRAL #2 | May 25 | Jun 6 | May 12 | Aug 26 | 92 |
| COLD BAY AP | May 25 | Jun 10 | May 9 | Oct 4 | 131 |
| DENALI 27 N | May 25 | Jun 3 | May 13 | Sep 8 | 105 |
| KALTAG AP | May 25 | Jun 11 | May 10 | Sep 3 | 101 |
| KING SALMON | May 26 | Jun 11 | May 9 | Sep 15 | 111 |
| NORTHWAY AP | May 26 | Jun 8 | May 13 | Sep 1 | 97 |
| WHITESTONE FARMS | May 26 | Jun 9 | May 14 | Sep 2 | 98 |
| HEALY | May 27 | Jun 10 | May 11 | Sep 1 | 97 |
| HOMER 9 E | May 27 | Jun 8 | May 14 | Sep 22 | 116 |
| MONASHKA CREEK DAM | May 27 | Jun 10 | May 8 | Sep 23 | 117 |
| PORTAGE GLACIER V C | May 27 | Jun 11 | May 12 | Sep 12 | 106 |
| AMBER LAKE | May 28 | Jun 9 | May 14 | Sep 13 | 107 |
| CAMPBELL CREEK SCI CTR | May 28 | Jun 6 | May 17 | Sep 12 | 107 |
| FOX 2 SE | May 28 | Jun 9 | May 14 | Sep 1 | 96 |
| GUSTAVUS 2 NE | May 28 | Jun 12 | May 12 | Sep 25 | 116 |
| MILE 42 STEESE | May 28 | Jun 19 | May 15 | Aug 26 | 87 |
| PORT ALCAN | May 28 | Jun 10 | May 15 | Aug 29 | 91 |
| EAGLE | May 29 | Jun 11 | May 18 | Aug 23 | 86 |
| TANANA CALHOUN MEM AP | May 29 | Jun 16 | May 15 | Aug 28 | 89 |
| WHITES CROSSING | May 29 | Jun 9 | May 13 | Sep 7 | 100 |
| DRY CREEK | May 30 | Jun 13 | May 16 | Aug 24 | 84 |
| FAREWELL LAKE | May 30 | Jun 15 | May 12 | Sep 5 | 97 |
| GUSTAVUS | May 30 | Jun 22 | May 14 | Sep 16 | 107 |
| LAKE SUSITNA | May 30 | Jun 9 | May 20 | Sep 4 | 95 |
| TWO RIVERS | May 30 | Jun 13 | May 12 | Sep 2 | 95 |
| MOOSE PASS 3NW | May 31 | Jun 15 | May 19 | Sep 8 | 99 |
| SILVER LAKE | May 31 | Jun 10 | May 20 | Sep 3 | 95 |
| ST GEORGE ISLAND AP | May 31 | Jun 23 | May 10 | Oct 5 | 128 |
| GILMORE CREEK | Jun 1 | Jun 17 | May 18 | Aug 28 | 87 |
| KENAI 29 ENE | Jun 1 | Jun 18 | May 21 | Sep 8 | 94 |
| SUTTON 1 W | Jun 1 | Jun 13 | May 20 | Sep 6 | 98 |
| HAYES RIVER | Jun 2 | Jun 11 | May 21 | Sep 8 | 98 |
| PORT ALSWORTH 1 SW | Jun 2 | Jun 13 | May 22 | Sep 12 | 101 |
| TOK #2 | Jun 3 | Jul 13 | May 22 | Aug 27 | 79 |
| DELTA 5 NE | Jun 4 | Jul 17 | May 25 | Aug 22 | 75 |
| INTRICATE BAY | Jun 4 | Jun 22 | May 18 | Sep 12 | 98 |
| NABESNA | Jun 4 | Jul 3 | May 18 | Sep 1 | 85 |
| ST PAUL ISLAND AP | Jun 4 | Jun 25 | May 16 | Sep 28 | 114 |
| DELTA JUNCTION 20 SE | Jun 5 | Jun 30 | May 25 | Aug 21 | 75 |
| GLENNALLEN 64 N | Jun 5 | Jun 21 | May 27 | Aug 24 | 76 |
| KOTZEBUE RALPH WEIN AP | Jun 5 | Jun 17 | May 20 | Sep 24 | 110 |
| NOME MUNI AP | Jun 5 | Jun 26 | May 20 | Sep 3 | 88 |
| ST. PAUL 4 NE | Jun 5 | Jul 1 | May 16 | Sep 28 | 110 |
| MCKINLEY PARK | Jun 6 | Jun 30 | May 22 | Aug 25 | 77 |
| GULKANA AP | Jun 7 | Jul 5 | May 24 | Aug 21 | 73 |
| PUNTILLA | Jun 7 | Jun 30 | May 25 | Sep 2 | 83 |
| KING SALMON 42 SE | Jun 9 | Jun 22 | May 28 | Sep 11 | 93 |
| KIVALINA AP | Jun 10 | Jun 23 | May 24 | Sep 11 | 92 |
| SOLDOTNA 5SSW | Jun 11 | Jul 7 | May 26 | Sep 1 | 75 |
| COOPER LANDING 5 W | Jun 12 | Jul 2 | May 29 | Sep 1 | 78 |
How to read the three dates
Average is the date by which, in half of the years between 1991 and 2020, the last 32 °F night had already happened. Safe is later: only one year in ten saw a frost after it, which is the date to set out frost-tender plants such as dahlia tubers and zinnia seedlings. Early is the risky end, with a frost after it in nine years out of ten.
Every figure is for the weather station, not for your garden. A valley bottom, a north slope or a spot near a lake can run a week or two either way. Cities are warmer than the countryside around them.
Where the numbers come from
The dates are NOAA's U.S. Climate Normals for 1991 to 2020, computed by the National Centers for Environmental Information for every station with thirty years of daily minimum temperatures. ZIP codes are matched to the nearest such station within 150 km using U.S. Census Bureau ZIP Code Tabulation Area centroids. Stations that never see a frost, such as much of south Florida, report no date and are left out.