Glenburn, ND 58740 Frost Dates
58740, near Glenburn, ND: the frost window
Around 05/11 is the usual last spring frost, about 256 days away. Fall's first freeze usually shows up around 09/29, roughly 138 days after the last spring frost.
Glenburn sits in USDA Zone 4a (-30 to -25°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
Stretching the season past the first frost
Glenburn's growing season runs out in roughly 5 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
The actual range around Glenburn's last frost
05/11 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/28 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/29 and only about 1 year in 10 sees frost after that.
Glenburn against the rest of the dataset
Glenburn's growing season runs about 138 days, ranking 37,448 of 40,283 US ZIP codes measured here, longest to shortest. Within ND, it ranks 189 of 405.
Learn more
Two guides worth reading on 58740: zone vs. frost date, on why Zone 4a and Glenburn's frost date answer different questions, and the frost range, on how to read the range around Glenburn's dates instead of trusting one.