National Weather ServiceSouth DakotaDense Fog AdvisoryArchive to October 1, 2026
Dense Fog Advisories in South Dakota
The National Weather Service issued 48 dense fog advisories for South Dakota in 2025 and 34 a year on average in 2008-2025; in 2021-2025 it had the 21st most of any state. 2026 through September: 49, 99% above the average of 25 for those months in 2008-2025. Moody was covered most often (187 times since 2008).
How many dense fog advisories does South Dakota get?
Every dense fog advisory that covered part of South Dakota. 2026 is an outline: the year is not over.
The numbers
| Year | Count |
|---|---|
| 2026 (through September) | 49 |
| 2025 | 48 |
| 2024 | 74 |
| 2023 | 80 |
| 2022 | 14 |
| 2021 | 40 |
| 2020 | 37 |
| 2019 | 48 |
| 2018 | 43 |
| 2017 | 26 |
| 2016 | 29 |
| 2015 | 15 |
| 2014 | 13 |
| 2013 | 14 |
| 2012 | 38 |
| 2011 | 17 |
| 2010 | 46 |
| 2009 | 13 |
| 2008 | 16 |
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 South Dakota 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 South Dakota?
| County or forecast zone | Since 2008 | Since 2023 | Last issued |
|---|---|---|---|
| Moody | 187 | 64 | September 30, 2026 |
| Grant | 178 | 61 | September 28, 2026 |
| Codington | 176 | 60 | September 30, 2026 |
| Minnehaha | 176 | 61 | September 30, 2026 |
| Edmunds | 175 | 67 | September 27, 2026 |
| Deuel | 174 | 60 | September 30, 2026 |
| Hamlin | 174 | 60 | September 30, 2026 |
| Lake | 174 | 66 | September 30, 2026 |
| Brown | 171 | 53 | September 27, 2026 |
| Brookings | 170 | 60 | September 30, 2026 |
| McPherson | 169 | 63 | September 27, 2026 |
| Lincoln | 168 | 62 | September 30, 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.
What is a dense fog advisory?
A dense fog advisory means fog will cut visibility to a quarter mile or less over a wide area. An advisory is issued for a hazard less serious than a warning that can still cause inconvenience or danger if people are not careful. The national record · Every warning type in South Dakota.