National Weather ServiceIowaExtreme Heat WarningArchive to October 1, 2026
Extreme Heat Warnings in Iowa
The National Weather Service issued 9 extreme heat warnings for Iowa in 2025 and 5 a year on average in 2008-2025; in 2021-2025 it had the 17th most of any state. 2026 through September: 13, 182% above the average of 5 for those months in 2008-2025. Pottawattamie was covered most often (24 times since 2008).
How many extreme heat warnings does Iowa get?
Every extreme heat warning that covered part of Iowa. 2026 is an outline: the year is not over.
The numbers
| Year | Count |
|---|---|
| 2026 (through September) | 13 |
| 2025 | 9 |
| 2024 | 12 |
| 2023 | 10 |
| 2022 | 4 |
| 2021 | 0 |
| 2020 | 2 |
| 2019 | 7 |
| 2018 | 4 |
| 2017 | 3 |
| 2016 | 6 |
| 2015 | 2 |
| 2014 | 0 |
| 2013 | 1 |
| 2012 | 7 |
| 2011 | 10 |
| 2010 | 4 |
| 2009 | 2 |
| 2008 | 0 |
Source: Iowa Environmental Mesonet archive of National Weather Service watches, warnings and advisories (VTEC); National Weather Service. Data as of October 1, 2026.
When in the year does Iowa get them?
Sum of 2008-2025; the busiest month is labelled.
Source: Iowa Environmental Mesonet archive of National Weather Service watches, warnings and advisories (VTEC); National Weather Service. Data as of October 1, 2026.
Where in Iowa?
| County or forecast zone | Since 2008 | Since 2023 | Last issued |
|---|---|---|---|
| Pottawattamie | 24 | 12 | July 25, 2026 |
| Mills | 23 | 12 | July 25, 2026 |
| Scott | 22 | 7 | September 2, 2026 |
| Page | 21 | 11 | July 25, 2026 |
| Muscatine | 21 | 7 | September 2, 2026 |
| Montgomery | 21 | 11 | July 25, 2026 |
| Johnson | 21 | 7 | September 2, 2026 |
| Fremont | 21 | 11 | July 25, 2026 |
| Washington | 20 | 7 | September 2, 2026 |
| Van Buren | 20 | 7 | September 2, 2026 |
| Louisa | 20 | 7 | September 2, 2026 |
| Lee | 20 | 7 | September 2, 2026 |
The NWS issues these products for counties or forecast zones; a zone can be part of a county or a mountain range.
Source: Iowa Environmental Mesonet archive of National Weather Service watches, warnings and advisories (VTEC); National Weather Service. Data as of October 1, 2026.
The latest extreme heat warnings for Iowa in AreaZine's record
NWS Quad Cities IAWarningSeptember 2, 2026
Extreme Heat Warning: Iowa, Johnson, Cedar and 21 more, IA and IL
Expired 7:00 p.m. CDT, September 4, 2026
NWS Omaha/ValleyWarningJuly 27, 2026
Extreme Heat Warning: Harrison and Shelby, IA
Expired 10:00 p.m. CDT, July 27, 2026
NWS La CrosseWarningJuly 26, 2026
Extreme Heat Warning: Mitchell, Howard, Winneshiek and 12 more, IA and MN
Expired 9:00 p.m. CDT, July 27, 2026
NWS Sioux FallsWarningJuly 25, 2026
Extreme Heat Warning: Lyon, Osceola, Dickinson and 20 more, IA and MN
Expired 8:00 p.m. CDT, July 26, 2026
NWS Omaha/ValleyWarningJuly 25, 2026
Extreme Heat Warning: Monona, Thurston, Wayne and 9 more, IA and NE
Expired 7:00 a.m. CDT, July 27, 2026
NWS Des MoinesWarningJuly 25, 2026
Extreme Heat Warning: Worth, Cerro Gordo, Franklin and 1 more, IA
Expired 9:00 p.m. CDT, July 26, 2026
NWS Quad Cities IAWarningJuly 25, 2026
Extreme Heat Warning: Buchanan, Delaware, Dubuque and 30 more, IA and IL
Expired 9:00 p.m. CDT, July 26, 2026
NWS Sioux FallsWarningJuly 20, 2026
Extreme Heat Warning: Plymouth, Cherokee, Buena Vista and 6 more, IA and NE
Expired 8:00 p.m. CDT, July 20, 2026
This list is AreaZine's record of the NWS alert feed, kept since April 6, 2026; the counts above come from the complete IEM archive.
Source: National Weather Service alerts (api.weather.gov).
What is an extreme heat warning?
An extreme heat warning means dangerous heat is expected, measured by heat index or temperature thresholds each office sets. It replaced the excessive heat warning in 2025. A warning means the hazard is happening, about to happen, or very likely: act now to protect people and property. AreaZine's counts include the excessive heat warnings issued before the change. The national record · Every warning type in Iowa.