1 flood insurance claims·$40,524 paid·4 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 Union County, South Carolina. 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.
Flash flooding and general river flooding from heavy rainfall events dominate the flood profile of Union County, South Carolina. Over the last 30 years, recorded events in the NOAA Storm Events Database include 9 flash floods, 7 floods, and 2 tropical storms.
Major historical impacts are illustrated by severe weather systems, such as Tropical Storm Helene in September 2024, which brought heavy rainfall and thunderstorms from a predecessor rain event, and Tropical Storm Michael in October 1918 (recorded in NOAA data as October 2018), which brought gusty winds and tree damage across the Piedmont. Additionally, slow-moving thunderstorms triggered localized flash flooding, as recorded in July 2013.
Homeowners, journalists, and real estate agents should pay the most attention to properties located within Special Flood Hazard Area Zone A, which accounts for the county's National Flood Insurance Program claims history. Specifically, properties in Zone A should monitor risk closely, as evidenced by a recorded claim average payout of $40,524 and an average recorded water depth of 0 inches.
Summary written from NOAA storm reports and NFIP claims for this county. Not a prediction.
3 NOAA storm reports from Union County describe what happened, in the words of the forecasters who covered it. Read the South Carolina flood stories →
23 federal disaster declarations since 1977, 4 of them floods, coastal storms or hurricanes.
| Disaster | Began |
|---|---|
| Severe Winter Storm | Jan 21, 2026 |
| Hurricane Helene | Sep 25, 2024 |
| Hurricane Debby | Aug 4, 2024 |
| Tropical Storm Debby | Aug 4, 2024 |
| Hurricane Idalia | Aug 29, 2023 |
| Hurricane Ian | Sep 25, 2022 |
| Hurricane Dorian | Aug 31, 2019 |
| Hurricane Florence | Sep 8, 2018 |
Weather and water disasters only; most recent first. Source: OpenFEMA Disaster Declarations.
18 since 1996: 9 flash floods and 7 river or area floods.
| Event | Date | Damage |
|---|---|---|
| Tropical Storm | Sep 27, 2024 | $2.0M |
| Tropical Storm | Oct 11, 2018 | — |
| Flash Flood | Jul 11, 2013 | — |
| Flash Flood | May 31, 2010 | — |
| Flood | Oct 7, 2005 | — |
| Flash Flood | Sep 7, 2004 | $250,000 |
| Flood | May 22, 2003 | — |
| Flood | Mar 20, 2003 | — |
— = no damage estimate in the record. Source: NOAA Storm Events Database.
Tropical Storm · Sep 27, 2024. Tropical Cyclone Helene began organizing over the western Caribbean on the 23rd and 24th of September before rapidly intensifying as it moved north through the eastern Gulf of Mexico on the 25th and 26th. A plume of moisture extending from the intensifying storm interacted with a slow-moving cold front to produce a band of widespread heavy rain showers and embedded scattered thunderstorms over the southern Appalac…
Tropical Storm · Oct 11, 2018. Tropical cyclone Michael gradually weakened as it tracked from the South Carolina Midlands through portions of the South Carolina and North Carolina Piedmont throughout the 11th. Gusty winds increased to 35 to 45 mph during the daylight hours on the east side of the storm track, with numerous trees blown across the Piedmont.
Flash Flood · Jul 11, 2013. Slow moving thunderstorms dropped very heavy rain over the northeast piedmont of South Carolina, resulting in flash flooding.
Flash Flood · May 31, 2010. A large area of rain and embedded thunderstorms caused a small area of flash flooding right as the precipitation was ending over the Upstate.
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 Union 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.