Monthly Weather Report

Iowa Monthly Weather Summary – June 2025

General Summary

Temperatures averaged 72.2 degrees or 2.3 degrees above normal while precipitation totaled 5.89 inches or 0.63 inch above normal. June 2025 ranks as the 24th warmest and 37th wettest June in 153 years of statewide records. A warmer June occurred in 2021, while a wetter one occurred in 2018.

Temperatures

Statewide temperatures were warmer than normal across Iowa with the warmest conditions found in east-central Iowa. Pockets along the Iowa-Minnesota and Iowa-Missouri borders reported near-normal monthly temperatures.

A notable event occurred from June 20-22 with exceedingly warm daytime temperatures in concert with high dewpoints and sustained strong southerly winds. These combined factors produced anomalous conditions not seen at many locations in the observational record. Afternoon temperatures rapidly warmed into the upper 90s in western Iowa with 80s farther east as southerly winds increased on the 20th. Strong southerly winds continued overnight into the 21st, helping set several record warm low temperatures for the date; the National Weather Service office in Davenport (Scott County) hit 82 degrees with a statewide low of 72 degrees, 11 degrees above normal. Conditions were nearly identical through the 22nd.

June’s statewide average maximum temperature was 83.0 degrees, 2.4 degrees above normal while the average minimum temperature was 61.4 degrees, 2.2 degree above normal. Little Sioux (Harrison County) reported the month’s high temperature of 101 degrees on the 20th, 17 degrees above normal. Mount Ayr (Ringgold County) and Stanley (Buchanan County) reported the month’s low temperature of 43 degrees on the 10th, on average 15 degrees below normal.

Cooling Degree Days

Home cooling requirements, as estimated by cooling degree day totals, averaged 2% more than last June and 32% more than normal. Cooling degree day totals are running 6% less than last year at this time and 21% more than normal.

Precipitation

Overall statewide precipitation through June was above normal across much of the western two-thirds of the state. A large north-to-south swath across central Iowa saw 125-150% of normal precipitation in June. The wettest conditions were found along the Iowa-Missouri border and a pocket in northwest Iowa where 175-200% of normal was located. East-central Iowa experienced the driest conditions with 50-75% of normal.

A cold front pushed into western Iowa into the evening hours on the 2nd with initial, isolated severe-warned thunderstorms firing from the afternoon heat. Wind damage to a hog barn was reported in Hospers (Sioux County) from a localized downburst along with heavy downpours. Scattered showers and thunderstorms expanded across western Iowa overnight into the 3rd and spread into eastern Iowa through the daytime hours. With rain and overcast skies, afternoon temperatures held in the upper 50s behind the front while upper 70s were observed in eastern Iowa, where atmospheric instability was present. Severe thunderstorms developed along the cold front and spawned an EF-0 tornado in New Boston (Lee County) and an EF-1 tornado south of the Quad Cities. The system exited the state by daybreak on the 4th with widespread rainfall totals reported at 7:00 am. Nearly 30 stations registered at least 2.00 inches with the highest amounts found in northwest and eastern Iowa; Le Claire Lock and Dam (Scott County) collected 2.01 inches while Sioux Center (Sioux County) hit 3.73 inches. Much of east-central Iowa observed totals in the 0.25-0.50 inch range; the statewide average amount was 0.94 inch. Showers moved into western Iowa later on the 5th and propagated through northern Iowa into the morning of the 6th. Rain amounts were under a few tenths of inch over the state’s northwestern half. On the 7th, a complex of moderate showers moved along the Iowa-Missouri border and into central Iowa through the day with several stations collecting more than an inch; Perry (Dallas County) observed 1.18 inches while Jefferson (Greene County) picked up 1.63 inches.

Showers pushed across southern Iowa on the afternoon of the 8th as a cold front dropped through the state. Rainfall totals were generally under 0.20 inch with most stations reporting less than 0.10 inch; a 0.21-inch-total was found in Murray (Clarke County). A stationary front draped over northern Iowa on the 11th was a forcing mechanism for strong to severe thunderstorms during the afternoon and evening hours. Several storms produced large hail and severe straight-line winds along a line from Rock Rapids (Lyon County) to Urbana (Benton County). There were numerous reports of crop and tree damage from larger hail and wind-driven hail. Moderate to heavy rain and training thunderstorms also brought significant totals to north-central Iowa; Nashua (Floyd County) observed 2.10 inches while Mason City (Cerro Gordo County) collected 3.22 inches. Many stations along the eastern and western periphery reported amounts in the 0.50 to 1.00-inch with lesser totals farther south. Winds turned easterly into the 12th with some lingering showers in northern Iowa with otherwise clear conditions. Scattered thundershowers popped up from south-central to northeastern Iowa during the late afternoon into the nighttime hours. Several stations reported heavier amounts, varying from 1.02 inches in Davis City (Decatur County) to 2.20 inches in Osage (Mitchell County). A few isolated thunderstorms developed in north-central Iowa around sunset on the 13th with showers moving over extreme southeastern Iowa; rain totals were under a few tenths of an inch. As temperatures warmed on the 14th, showers and thunderstorms developed along a surface boundary from central to northwestern Iowa, where some cells became severe-warned. The complex expanded over most of northern Iowa with the highest amounts in Hamilton County where two Webster City gauges collected 2.61 and 2.84 inches. Twenty-five stations reported at least an inch with widespread 0.25 to 0.50-inch totals reported at 7:00 am on the 15th.

Showers and thunderstorms reformed in central and eastern Iowa during the evening hours with another pulse of development in north-central Iowa towards daybreak on the 16th. This complex moved southeast over eastern Iowa for much of the day as severe thunderstorms fired in western Iowa during the late afternoon. The line became severe-warned as it raced through west-central Iowa, but lost strength as it fanned out into central and southwest Iowa by sunset. Rain totals reported on the morning of the 17th were highest in northern Iowa, where Nora Springs (Floyd County) observed 2.28 inches while Lake Mills (Winnebago County) collected 3.25 inches. Several surrounding stations reported 1.00 inch or more with a north-central to southeast swath of at least 0.50 inch. Much of western Iowa also registered 0.25 to 0.50 inch. Later in the day, slow-moving thunderstorms brought heavier rain to northern Iowa, especially around Orange City (Sioux County) where several gauges registered from 1.58 inches to 3.02 inches. Rainfall continued into the 18th with persisting clouds and thundershowers rumbling across central Iowa. Conditions quieted down after midnight with rain totals for the previous 24 hours that were particularly high in southeastern Iowa where a 2.59-inch reading was collected in Ottumwa (Wapello County) and a 3.65-inch reading in Drakesville (Davis County).

Clouds increased towards the evening hours of the 19th with thunderstorms forming in central Iowa as well as an isolated severe-warned cell in southwest Iowa; a 74-mph wind gust was observed near Tabor (Mills County). Another severe-warned line dove south, from Kossuth County into east-central Iowa by sunrise on the 20th. Along this swath, numerous stations reported over 0.75 inch with locally heavy totals at north-central and east-central stations; Mason City hit 2.43 inches with 3.00 inches in Grinnell (Poweshiek County). Thunderstorms with downpours continued across eastern Iowa before moving out of the state by evening. Clouds increased over western Iowa into the morning of the 23rd as a cold front moved through northwestern Iowa with morning lows hovering in the 70s. With ample moisture and temperatures in the 80s and low 90s, thunderstorms blossomed along the cold front from northeast to southwest into the evening hours, producing locally heavy rain and scattered severe wind gusts. Steady rain persisted across southern Iowa where Flash Flood Warnings were issued during the late morning.  Redevelopment of sluggish thunderstorms occurred over Iowa’s southern third around sunset and pushed into west-central Iowa by daybreak on the 24th with additional flood warnings issued. Numerous stations from central to southwestern Iowa reported totals over 3.00 inches, with Decatur County stations of Davis City and Grand River collecting 3.05 to 5.00-inch totals, respectively. A wide swath of 1.00 to 3.00-inch totals stretched from south-central to northeast Iowa while lesser amounts were registered northwest; the overall statewide average was 0.82 inch. Portions of western Iowa experienced widespread rainfall beginning on the 25th as another system propagated across Iowa, producing some severe straight-line winds along with local flooding in west-central counties. Over 120 stations observed at least an inch with 3.12 inches in Urbandale (Polk County) and 5.57 inches in Massena (Cass County). Amounts of 0.25-0.50 inch were widespread over the southwestern corner.

The 26th was another severe weather day over Iowa as a cold front transited the Upper Midwest. Afternoon temperatures reached into the upper 80s and low 90s ahead of the surface boundary with thunderstorms firing rapidly from southwest to northeast. Several cells turned severe, with high winds and two weak tornadoes near Corwith (Hancock County) and Lu Verne (Humboldt County). The line of storms pushed into eastern Iowa and finally out of the southwest corner by dawn on the 27th. Most Iowa stations received at least 0.50 inch with a west to north-central band of 2.00-4.00 inches; Carroll (Carroll County) observed 2.05 inches with 4.00 inches in Odebolt (Sac County). Winds shifted southerly into the 28th with light rain in northwestern Iowa. Conditions quickly changed by midnight in northwest Iowa as a bow echo with severe-warned thunderstorms dropped large hail and strong wind gusts; a 75-mph reading was observed near Cleghorn (Cherokee County). The complex diminished in strength early on the 29th with a few stations registering higher rainfall totals; Sioux Center hit 1.01 inches. Thunderstorms refired along a cold front in northeastern Iowa and held together into the early hours of the 30th before falling apart. Rain amounts were highest in southern and northeast Iowa where many stations collected more than an inch; Elkader (Clayton County) reported 1.14 inches while Promise City (Wayne County) observed 2.61 inches.

US Drought Monitor (USDM)

The US Drought Monitor showed improvement across much of the state as a result of above-normal rainfall through June. At the beginning of June, Abnormal Dryness (D0) covered 59% of Iowa with 13% coverage of Moderate Drought (D1). As of July 1, 43% of Iowa was rated at some level of dryness or drought. D0 covered much of the eastern and western thirds of Iowa, with an overall coverage of 38%. Four small pockets of Moderate Drought (D1) were found in eastern, northwest, southwest and southeast Iowa, covering 5% of the state. According to Iowa Drought Plan (IDP) trigger tables updated on June 5th, Drought Regions 1 and 4 are classified as in a “Watch.”

Justin Glisan, Ph.D.
State Climatologist of Iowa
Iowa Dept. of Agriculture & Land Stewardship
Wallace State Office Bldg.
Des Moines, IA 50319
Telephone: (515) 281-8981
E-mail: Justin.Glisan@IowaAgriculture.gov

Weather by Districts

* Departures are computed from 1991-2020 normals.
The weather data in this report are based upon information collected by the U. S. Dept. of Commerce, NOAA National Weather Service.