Lisbon, ND 58054 Frost Dates
Lisbon, ND: when does the frost end?
Around 05/03 is the usual last spring frost, about 248 days away. Fall's first freeze usually shows up around 10/05, roughly 155 days after the last spring frost.
Zone 4a (-30 to -25°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Lisbon, not a forecast for this year.
Stretching the season past the first frost
With roughly 5 weeks until Lisbon's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 05/03 isn't a guarantee
05/03 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 05/16 and only about 1 year in 10 sees frost after that.
Lisbon against the rest of the dataset
Lisbon's growing season runs about 155 days, ranking 33,994 of 40,283 US ZIP codes measured here, longest to shortest. Within ND, it ranks 19 of 405.
Learn more
Before leaning on 58054's figures: zone vs. frost date explains why Zone 4a and Lisbon's frost date answer different questions, while the frost range explains how to read the range around Lisbon's dates instead of trusting one.