3 flood insurance claims·$167,335 paid·9 federal flood & hurricane disasters
Share of the whole county outline, rivers and lakes included; parts FEMA hasn’t mapped count as zero.
Shaded areas are FEMA’s mapped flood hazard zones in and around Gregory County, South Dakota. Zoomed out they are simplified; at street level the map switches to FEMA’s exact layer. Tap anywhere to check that spot, or search an address above.
River flooding and flash flooding from heavy rainfall events shape the primary flood hazards in Gregory County, with NOAA records documenting 9 flood events and 6 flash flood events over the last 30 years.
Significant heavy rainfall events drive these conditions, such as a multi-day storm from June 20 to June 22, 2024, that produced widespread totals between 5 and 15 inches across the region, leading to major river flooding and extensive overland flooding. A separate multi-day heavy rainfall event on September 12, 2019, set two-day records across multiple regional locations, while a March 13, 2019, event combined 1 to 3 inches of rainfall with a melting snowpack on frozen ground to produce considerable overland flooding and ponding.
National Flood Insurance Program records for the county show claims concentrated in Zone X Unshaded, totaling 3 claims with an average payout of $55,778 and an average recorded water depth of 0 inches. Property owners, real estate agents, and journalists should pay attention to areas subject to heavy rainfall accumulation, overland flooding, and river overflows.
Summary written from NOAA storm reports and NFIP claims for this county. Not a prediction.
6 NOAA storm reports from Gregory County describe what happened, in the words of the forecasters who covered it. Read the South Dakota flood stories →
24 federal disaster declarations since 1976, 9 of them floods, coastal storms or hurricanes.
| Disaster | Began |
|---|---|
| Severe Storms, Straight-line Winds, And Flooding | Jun 16, 2024 |
| Severe Storms, Tornadoes, And Flooding | Sep 9, 2019 |
| Severe Storms, Tornadoes, And Flooding | Jun 30, 2019 |
| Severe Storms And Flooding | May 21, 2019 |
| Severe Winter Storm, Snowstorm, And Flooding | Mar 13, 2019 |
| Flooding | Mar 11, 2011 |
| Flooding | Mar 10, 2010 |
| Severe Winter Storm | Jan 20, 2010 |
Weather and water disasters only; most recent first. Source: OpenFEMA Disaster Declarations.
15 since 1996: 6 flash floods and 9 river or area floods.
| Event | Date | Damage |
|---|---|---|
| Flood | Jun 21, 2024 | $352,000 |
| Flood | Mar 13, 2019 | $1.4M |
| Flood | Sep 12, 2019 | $205,000 |
| Flash Flood | Aug 9, 2019 | $5,000 |
| Flash Flood | Aug 9, 2019 | $630,000 |
| Flood | Jun 1, 2019 | — |
| Flash Flood | Jul 12, 2018 | — |
| Flood | Jun 1, 2011 | — |
— = no damage estimate in the record. Source: NOAA Storm Events Database.
Flood · Jun 21, 2024. A multi-day significant heavy rainfall event from June 20-22 resulted in widespread rain totals between 5 and 10 inches with pockets in excess of 15 inches across portions of southeast South Dakota, northwest Iowa, and southwest Minnesota. As rainfall reached area streams and rivers, major to record flooding was observed, devastating several towns and communities. Extensive overland flooding also resulted in signi…
Flood · Mar 13, 2019. Rainfall of one to three inches on frozen ground and into a snow pack with between 2 and 5 inches of liquid water equivalent resulted in considerable overland flooding.||One of the hardest hit areas was around Yankton, where a No Travel Advisory was issued for the city on March 13-14. Businesses along north Highway 81 toward Yankton Mall had considerable ponding of water. Water rescues were necessary as cars sta…
Flood · Sep 12, 2019. A frontal zone remained locked in place under southwest flow aloft as a series of mid-level waves moved across the region over a three day period. Widespread heavy rainfall resulted and amounts reached two-day records for several locations including Platte (6.29 inches), White Lake (6.28 inches), Bridgewater (8.05 inches), Montrose (5.63 inches), Alexandria (8.30 inches), Madison (7.63 inches), Howard (7.05 inche…
Flash Flood · Aug 9, 2019. Scattered thunderstorms developed across central South Dakota during the late afternoon hours and moved southeast into an environment of deep mixed-layer instability and effective shear of around 50 knots in the evening. Storms transformed into short bowing segments as they moved along the main instability gradient toward the lower James River Valley.
National Weather Service narratives, lightly trimmed. Source: NOAA Storm Events Database.
Every colour on the map above is a place on this drawing: where the ground sits relative to the flood FEMA plans for.
If a building in Gregory County is in a high-risk zone (A or V) and its mortgage comes from a federally regulated or insured lender, or is federally backed, flood insurance is required.
Outside those zones it is optional, and often worth having: from 2014 to 2024 nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area. Since Risk Rating 2.0, NFIP premiums are set for each building, so the only reliable price is a quote: FloodSmart.gov or a local agent.