NOAA NCEI Climate Normals 1991–2020

Iowa Weather by Month

Temperature, rain and the hurricane season at 117 Iowa stations, month by month.

Data: NOAA NHC HURDAT2 and NOAA SPC tornado and hail reports, through 2025 · Updated October 26, 2026

The median station records 36.8 inches of precipitation a year; Lamoni, IA records the most, 41.2 inches, and Spirit Lake, IA the least, 29.0 (1.4 times as much). July is the hottest month at the median station (average high 84°F); the hottest July is at Lamoni, IA, 87°F. January is the coldest (average low 10°F); the coldest January nights are at Northwood, IA, 4°F. Highs reach 90°F on 15 days a year at the median station and on 34 at Glenwood 3SW, IA, the most. Snowfall is heaviest at Mason City Municipal Airport, IA, 44.4 inches a year.

This page compares the 1991–2020 NOAA climate normals of 117 Iowa weather stations, each the nearest station with full normals to at least one of the 241 Iowa cities on this site that have one within 25 miles.

At the median station, June is the wettest month (5.3 inches) and January the driest (1.0). Station by station, the wettest month is June at 88 and May at 29 of the 117, and the driest January at 112, February at 4 and December at 1. The gap between the wettest and driest station is widest in June: 2.5 inches.

Month by month across Iowa

Iowa climate normals by month: median of 117 stations and the station at each extreme
Month	High °F	Low °F	Precip. in	Hottest days	Coldest nights	Wettest	Driest
Jan	28	10	1.0	Shenandoah, IA33°	Northwood, IA4°	Oskaloosa, IA1.8"	Onawa 3NW, IA0.5"
Feb	33	14	1.2	Shenandoah, IA39°	Northwood, IA8°	Columbus Junction, IA1.9"	Estherville Municipal Airport, IA0.5"
Mar	46	25	2.0	Shenandoah, IA52°	Northwood, IA21°	Fort Madison, IA2.7"	Spirit Lake, IA1.4"
Apr	60	37	3.8	Glenwood 3SW, IA64°	Sheldon, IA32°	Hampton, IA4.3"	Rock Rapids, IA3.0"
May	71	49	4.9	Glenwood 3SW, IA74°	Northwood, IA45°	Shenandoah, IA6.2"	Le Mars, IA3.9"
Jun	81	59	5.3	Harlan, IA84°	Fayette, IA56°	Elkader 6 SSW, IA6.7"	Onawa 3NW, IA4.2"
Jul	84	63	4.2	Lamoni, IA87°	Northwood, IA59°	Dubuque L&D 11, IA5.3"	Le Mars, IA3.1"
Aug	82	60	4.2	Lamoni, IA86°	Northwood, IA57°	Oskaloosa, IA5.1"	Rock Rapids, IA3.1"
Sep	76	51	3.5	Glenwood 3SW, IA79°	Northwood, IA48°	Allerton, IA4.2"	Pocahontas, IA2.6"
Oct	63	39	2.8	Glenwood 3SW, IA67°	Sheldon, IA35°	Cascade, IA3.3"	Spirit Lake, IA2.1"
Nov	47	27	2.0	Shenandoah, IA51°	Sheldon, IA22°	Keokuk Lock Dam 19, IA2.6"	Glenwood 3SW, IA1.3"
Dec	33	16	1.5	Keokuk Lock Dam 19, IA38°	Sibley, IA11°	Donnellson, IA2.0"	Estherville Municipal Airport, IA0.5"

High, low and precipitation are the median of the 117 stations; the station columns name the station with the highest average high, the lowest average low, and the most and least precipitation that month, each linked to the city page it serves. Source: NOAA NCEI U.S. Climate Normals 1991–2020.

Iowa cities and their stations

Iowa city pages with the normals of their nearest station
City	Station	Miles	Hottest month high °F	Coldest month low °F	Year precip. in
Des Moines	Des Moines International Airport, IA	4	86	14	36.6
Ankeny	Ankeny, IA	2	86	12	37.2
West Des Moines	Des Moines International Airport, IA	6	86	14	36.6
Urbandale	Des Moines Wsfo-Johnston, IA	8	85	13	36.4
Bettendorf	Rock Island L&D 15, IL	5	84	13	38.7
Waukee	Des Moines International Airport, IA	12	86	14	36.6
Johnston	Des Moines Wsfo-Johnston, IA	4	85	13	36.4
Clive	Des Moines International Airport, IA	8	86	14	36.6
Grimes	Des Moines Wsfo-Johnston, IA	5	85	13	36.4
Norwalk	Des Moines International Airport, IA	5	86	14	36.6
Polk City	Des Moines Wsfo-Johnston, IA	3	85	13	36.4
Windsor Heights	Des Moines International Airport, IA	5	86	14	36.6
Cumming	Des Moines International Airport, IA	8	86	14	36.6

All Iowa cities and their storm history →

How stations are matched to cities and what normals are: methodology · other states by month