FrostDateCheck

Anchorage, AK 99599 Frost Dates

Anchorage, AK: when does the frost end?

Zone 5a

The last spring frost here typically falls around 05/01, about 246 days from today. Fall's first freeze usually shows up around 09/29, roughly 150 days after the last spring frost.

The USDA Plant Hardiness Zone Map puts Anchorage in Zone 5a (-20 to -15°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.

Stretching the season past the first frost

With roughly 5 weeks until Anchorage's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.

The actual range around Anchorage's last frost

05/01 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/19 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/09 and only about 1 year in 10 sees frost after that.

Anchorage against the rest of the dataset

At roughly 150 frost-free days, Anchorage places 35,240 of 40,283 ZIP codes in this dataset. Within AK, it ranks 52 of 269.

Learn more

Before leaning on 99599's figures: local microclimates explains what one yard in Anchorage can differ from the 99599 normal, while zone vs. frost date explains why Zone 5a and Anchorage's frost date answer different questions.