Iowa Weather
As the temperatures are starting to get cooler as we head into late September, the first frost of the season is right around the corner.
On average, the first frost in Iowa occurs as early as September 21st and as late as October 7th across the state of Iowa. This is based on historical records from 1981-2010.
On average, the first freeze occurs from mid to late October across the state of Iowa. This is also based on historical records from 1981-2010.
When the first freeze of the year occurs, this officially ends the growing season as the sub-freezing temperatures kill any vegetation. This is when a freeze warning will be issue as shown above.