DES MOINES, Iowa — October is here, and Mother Nature is finally starting to get the memo!
Although the month started with temperatures well above average, the warmth won't last long.
The first noticeable dip in temperatures is set to arrive on Friday and Saturday, and some spots could even see the first frost threat of the season over the weekend.
Frost refers to the "formation of thin ice crystals on the ground or other surfaces in the form of scales, needles, feathers, or fans," according to the National Weather Service.
It develops in similar conditions as dew, except temperatures of the Earth's surface or earthbound objects drop near or below 32°.
Frost happens most often on clear nights with calm winds, or when radiational cooling is prime, so it can occur even when ambient temperatures are in the mid to upper 30s.
Occasionally, frost spells concerns for the growing season.
If frost is thick enough, it can put an end to the growing season quickly, making it an important weather event for farmers and other outdoor workers.
On average, northwest Iowa sees frost for the first time at the end of September. For central, eastern and southern Iowa, the first frost tends to lie closer to early or mid October.
In Des Moines, the average first frost of the season occurs on or around Oct. 6.
Areas outside of Des Moines, like Ames and Fort Dodge, see the first frost of the season, on average, in the last week of September.
If Iowa does experience frost over the weekend, it will be close, or even a little behind, to average.
