Bield:Farm
Frost dates · Iowa

Iowa frost dates,
county by county.

Last spring frost and first fall frost probability data for all 99 counties in Iowa, computed from the NOAA 1991–2020 Climate Normals. Every county page surfaces the full probability table at three temperature thresholds plus crop-specific planting guidance.

Variation across Iowa

29 days separate the earliest and latest counties.

The median last spring frost in Des Moines County is March 31 — 29 days earlier than Howard County at April 29. Statewide averages aren't useful planting tools; pick your county below for the data that actually applies to your fields.

By geography

Iowa counties on the map.

Each dot is a county. Click for full frost-date detail. Color shows last-spring-frost timing — sage = earliest, amber = latest.

ListMap
Black Hawk County · Spring Apr 16 · Fall Oct 20 · 187-day seasonHancock County · Spring Apr 18 · Fall Oct 17 · 182-day seasonWapello County · Spring Apr 13 · Fall Oct 24 · 194-day seasonCedar County · Spring Apr 12 · Fall Oct 25 · 196-day seasonHoward County · Spring Apr 29 · Fall Oct 11 · 165-day seasonWarren County · Spring Apr 14 · Fall Oct 21 · 190-day seasonWayne County · Spring Apr 11 · Fall Oct 27 · 199-day seasonMarshall County · Spring Apr 17 · Fall Oct 18 · 184-day seasonFranklin County · Spring Apr 19 · Fall Oct 20 · 184-day seasonDelaware County · Spring Apr 23 · Fall Oct 15 · 175-day seasonBuchanan County · Spring Apr 20 · Fall Oct 17 · 180-day seasonWebster County · Spring Apr 17 · Fall Oct 19 · 185-day seasonBoone County · Spring Apr 16 · Fall Oct 22 · 189-day seasonRinggold County · Spring Apr 14 · Fall Oct 23 · 192-day seasonShelby County · Spring Apr 17 · Fall Oct 20 · 186-day seasonUnion County · Spring Apr 17 · Fall Oct 23 · 189-day seasonAdams County · Spring Apr 16 · Fall Oct 23 · 190-day seasonMahaska County · Spring Apr 11 · Fall Oct 27 · 199-day seasonAdair County · Spring Apr 16 · Fall Oct 23 · 190-day seasonHamilton County · Spring Apr 24 · Fall Oct 12 · 171-day seasonHardin County · Spring Apr 16 · Fall Oct 21 · 188-day seasonIda County · Spring Apr 17 · Fall Oct 21 · 187-day seasonMarion County · Spring Apr 10 · Fall Oct 29 · 202-day seasonPoweshiek County · Spring Apr 23 · Fall Oct 17 · 177-day seasonPolk County · Spring Apr 13 · Fall Oct 25 · 195-day seasonMadison County · Spring Apr 20 · Fall Oct 15 · 178-day seasonVan Buren County · Spring Apr 14 · Fall Oct 23 · 192-day seasonHenry County · Spring Apr 17 · Fall Oct 20 · 186-day seasonCerro Gordo County · Spring Apr 24 · Fall Oct 11 · 170-day seasonWright County · Spring Apr 19 · Fall Oct 19 · 183-day seasonJones County · Spring Apr 21 · Fall Oct 16 · 178-day seasonCarroll County · Spring Apr 16 · Fall Oct 21 · 188-day seasonGreene County · Spring Apr 15 · Fall Oct 21 · 189-day seasonEmmet County · Spring Apr 22 · Fall Oct 14 · 175-day seasonMitchell County · Spring Apr 17 · Fall Oct 20 · 186-day seasonMontgomery County · Spring Apr 15 · Fall Oct 23 · 191-day seasonBremer County · Spring Apr 18 · Fall Oct 20 · 185-day seasonWashington County · Spring Apr 17 · Fall Oct 22 · 188-day seasonO'Brien County · Spring Apr 18 · Fall Oct 21 · 186-day seasonPocahontas County · Spring Apr 16 · Fall Oct 17 · 184-day seasonDavis County · Spring Apr 6 · Fall Oct 31 · 208-day seasonCrawford County · Spring Apr 17 · Fall Oct 22 · 188-day seasonGrundy County · Spring Apr 19 · Fall Oct 18 · 182-day seasonAudubon County · Spring Apr 22 · Fall Oct 14 · 175-day seasonLinn County · Spring Apr 17 · Fall Oct 22 · 188-day seasonKeokuk County · Spring Apr 12 · Fall Oct 24 · 195-day seasonSac County · Spring Apr 19 · Fall Oct 17 · 181-day seasonWoodbury County · Spring Apr 19 · Fall Oct 18 · 182-day seasonPottawattamie County · Spring Apr 15 · Fall Oct 25 · 193-day seasonMuscatine County · Spring Apr 7 · Fall Oct 31 · 207-day seasonMills County · Spring Apr 12 · Fall Oct 21 · 192-day seasonOsceola County · Spring Apr 25 · Fall Oct 13 · 171-day seasonFayette County · Spring Apr 25 · Fall Oct 15 · 173-day seasonJasper County · Spring Apr 12 · Fall Oct 26 · 197-day seasonDes Moines County · Spring Mar 31 · Fall Nov 7 · 221-day seasonStory County · Spring Apr 14 · Fall Oct 23 · 192-day seasonPlymouth County · Spring Apr 20 · Fall Oct 16 · 179-day seasonAppanoose County · Spring Apr 17 · Fall Oct 24 · 190-day seasonDubuque County · Spring Apr 17 · Fall Oct 21 · 187-day seasonFremont County · Spring Apr 9 · Fall Oct 29 · 203-day seasonDecatur County · Spring Apr 19 · Fall Oct 19 · 183-day seasonWinneshiek County · Spring Apr 22 · Fall Oct 17 · 178-day seasonClay County · Spring Apr 22 · Fall Oct 14 · 175-day seasonJohnson County · Spring Apr 9 · Fall Oct 28 · 202-day seasonLucas County · Spring Apr 26 · Fall Oct 16 · 173-day seasonMonroe County · Spring Apr 12 · Fall Oct 26 · 197-day seasonIowa County · Spring Apr 18 · Fall Oct 19 · 184-day seasonBenton County · Spring Apr 25 · Fall Oct 12 · 170-day seasonKossuth County · Spring Apr 20 · Fall Oct 18 · 181-day seasonScott County · Spring Apr 12 · Fall Oct 24 · 195-day seasonHarrison County · Spring Apr 19 · Fall Oct 19 · 183-day seasonLouisa County · Spring Apr 15 · Fall Oct 21 · 189-day seasonPage County · Spring Apr 14 · Fall Oct 21 · 190-day seasonClayton County · Spring Apr 27 · Fall Oct 11 · 167-day seasonHumboldt County · Spring Apr 16 · Fall Oct 23 · 190-day seasonJefferson County · Spring Apr 15 · Fall Oct 22 · 190-day seasonSioux County · Spring Apr 21 · Fall Oct 14 · 176-day seasonDallas County · Spring Apr 16 · Fall Oct 22 · 189-day seasonCass County · Spring Apr 22 · Fall Oct 12 · 173-day seasonClarke County · Spring Apr 18 · Fall Oct 20 · 185-day seasonMonona County · Spring Apr 15 · Fall Oct 23 · 191-day seasonCalhoun County · Spring Apr 16 · Fall Oct 21 · 188-day seasonJackson County · Spring Apr 14 · Fall Oct 24 · 193-day seasonChickasaw County · Spring Apr 20 · Fall Oct 15 · 178-day seasonGuthrie County · Spring Apr 23 · Fall Oct 15 · 175-day seasonWinnebago County · Spring Apr 18 · Fall Oct 18 · 183-day seasonDickinson County · Spring Apr 21 · Fall Oct 17 · 179-day seasonLee County · Spring Apr 7 · Fall Nov 1 · 208-day seasonTaylor County · Spring Apr 14 · Fall Oct 26 · 195-day seasonButler County · Spring Apr 16 · Fall Oct 20 · 187-day seasonFloyd County · Spring Apr 21 · Fall Oct 17 · 179-day seasonWorth County · Spring Apr 24 · Fall Oct 13 · 172-day seasonCherokee County · Spring Apr 24 · Fall Oct 15 · 174-day seasonPalo Alto County · Spring Apr 16 · Fall Oct 20 · 187-day seasonTama County · Spring Apr 19 · Fall Oct 20 · 184-day seasonBuena Vista County · Spring Apr 15 · Fall Oct 23 · 191-day seasonLyon County · Spring Apr 21 · Fall Oct 16 · 178-day seasonAllamakee County · Spring Apr 21 · Fall Oct 22 · 184-day seasonClinton County · Spring Apr 14 · Fall Oct 24 · 193-day season
Last spring frostEarliestMedianLatest
99 counties · click any county for full frost data
Alphabetical

All Iowa counties — A to Z.

Frost dates set the calendar. Bield: Farm runs it.

Pair these dates with live forecasts for your specific farm location. Bield: Farm logs your soil tests, planting dates, weather, and yield outcomes year over year.

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