Enter any address in Union County, South Carolina to see its FEMA flood zone
Flash flooding from slow-moving thunderstorms is the dominant flood character in Union County, SC. Over the past 30 years, NOAA Storm Events data shows 9 flash flood events and 7 general flood events, alongside 2 tropical storm events. For example, slow-moving thunderstorms produced very heavy rain and flash flooding in July 2013. More recently, Tropical Cyclone Helene in September 2024 brought a plume of moisture that interacted with a cold front, resulting in widespread heavy rainfall over the region.
National Flood Insurance Program (NFIP) data indicates that properties in Zone A have experienced claims, with one claim averaging a payout of $40,524 for an average water depth of 0.0 feet. Residents in areas designated as Zone A, as well as those located near rivers or in low-lying areas, should pay the most attention to flood risk.
Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.
3 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.
Union County, South Carolina has recorded 18 flood-related events since 1996 according to NOAA's Storm Events Database, including 9 flash floods and 7 river or area floods. The county has received 23 federal disaster declarations, 1 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.
FEMA Disaster Declarations (1977–2026)
Source: OpenFEMA Disaster Declarations Summaries.
| Declaration | Type | Date |
|---|---|---|
| Severe Winter Storm | Winter Storm | Jan 21, 2026 |
| Hurricane Helene | Tropical Storm | Sep 25, 2024 |
| Hurricane Debby | Tropical Storm | Aug 4, 2024 |
| Tropical Storm Debby | Tropical Storm | Aug 4, 2024 |
| Hurricane Idalia | Hurricane | Aug 29, 2023 |
| Hurricane Ian | Hurricane | Sep 25, 2022 |
| Covid-19 | Biological | Jan 20, 2020 |
| Covid-19 Pandemic | Biological | Jan 20, 2020 |
| Hurricane Dorian | Hurricane | Aug 31, 2019 |
| Hurricane Florence | Hurricane | Sep 8, 2018 |
NOAA Storm Events Database (1996–2025)
Source: NOAA National Weather Service Storm Events Database.
| Type | Date | Damage |
|---|---|---|
| Tropical Storm | Sep 27, 2024 | 2.00M |
| Tropical Storm | Oct 11, 2018 | 0.00K |
| Flash Flood | Jul 11, 2013 | 0.00K |
| Flash Flood | May 31, 2010 | 0.00K |
| Flood | Oct 7, 2005 | — |
| Flash Flood | Sep 7, 2004 | 250K |
| Flood | May 22, 2003 | — |
| Flood | Mar 20, 2003 | — |
| Flood | Apr 18, 2003 | 100K |
| Flash Flood | Aug 5, 2003 | — |
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 ...
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.
Flash Flood — Sep 7, 2004
After an extended period of moderate to occasionally heavy rainfall, intensifying rain rates led to rapid rises and flash flooding along some small creeks and streams in eastern portions of the Upstate. Several roads were covered with water in areas from Gaffney to Blacksburg due to flooding of Cherokee Creek and other small streams. However, flooding was most severe near the city of Union, wh...
Source: NOAA National Weather Service Storm Events Database.
Source: OpenFEMA NFIP Individual Claims (2.25M records analyzed).
FEMA assigns flood zone designations to areas in Union County, South Carolina:
AE High Risk — 1% annual chance of flooding. Insurance required.
VE Very High Risk — Coastal flooding with wave action.
X (Shaded) Moderate Risk — 500-year floodplain.
X Low Risk — Outside major floodplains.
Properties in Union County, South Carolina that are in FEMA-designated Special Flood Hazard Areas (zones A and V) with federally backed mortgages are required to carry flood insurance.
Even outside high-risk zones, flood insurance is recommended. From 2014 to 2024, nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area.
Visit FloodSmart.gov to find an agent and get a quote.