Brighton, IA 52540 Frost Dates
52540, near Brighton, IA: the frost window
Typically, the last spring freeze lands around 04/27, roughly 242 days out. Fall's first freeze usually shows up around 10/12, roughly 168 days after the last spring frost.
Brighton sits in USDA Zone 5b (-15 to -10°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
Brighton's growing season runs out in roughly 6 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 Brighton's last frost
04/27 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/13 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/14 and only about 1 year in 10 sees frost after that.
Brighton against the rest of the dataset
At roughly 168 frost-free days, Brighton places 29,762 of 40,283 ZIP codes in this dataset. Within IA, it ranks 385 of 1,042.
Learn more
Two guides worth reading on 52540: local microclimates, on what one yard in Brighton can differ from the 52540 normal, and zone vs. frost date, on why Zone 5b and Brighton's frost date answer different questions.