Holy Cross, AK 99602 Frost Dates
99602, near Holy Cross, AK: the frost window
Around 05/21 is the usual last spring frost, about 266 days away. Fall's first freeze usually shows up around 09/22, roughly 122 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Holy Cross in Zone 3a (-40 to -35°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
Holy Cross's growing season runs out in roughly 4 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
How much risk comes with planting early here
05/21 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/08 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 06/02 and only about 1 year in 10 sees frost after that.
Holy Cross against the rest of the dataset
At roughly 122 frost-free days, Holy Cross places 38,984 of 40,283 ZIP codes in this dataset. Within AK, it ranks 129 of 269.
Learn more
Two guides worth reading on 99602: local microclimates, on what one yard in Holy Cross can differ from the 99602 normal, and zone vs. frost date, on why Zone 3a and Holy Cross's frost date answer different questions.