Enter any address in Karnes County, Texas to see its FEMA flood zone
Flash flooding from thunderstorms is the dominant flood character in Karnes County. Between 2004 and 2023, NOAA Storm Events data recorded 75 flash flood events and 17 flood events. For example, on May 13, 2023, slow-moving thunderstorms produced locally heavy rain, leading to flash flooding. Another event on May 10, 2023, also saw locally heavy rain from thunderstorms causing flooding.
NFIP claims data indicates that properties in Zone A have experienced the most frequent and severe flooding, with an average water depth of 6.0 feet and an average payout of $13,343. While Zone X and Zone X_Unshaded properties have also filed claims, the average water depth and payouts were significantly lower. Homeowners in Zone A, and those located near waterways or in areas prone to rapid water level rise, should pay the most attention to flood risk.
Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.
22 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.
Karnes County, Texas has recorded 94 flood-related events since 1996 according to NOAA's Storm Events Database, including 75 flash floods and 17 river or area floods. The county has received 16 federal disaster declarations, 2 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.
FEMA Disaster Declarations (1967–2021)
Source: OpenFEMA Disaster Declarations Summaries.
| Declaration | Type | Date |
|---|---|---|
| Severe Winter Storm | Severe Ice Storm | Feb 11, 2021 |
| Severe Winter Storms | Severe Ice Storm | Feb 11, 2021 |
| Covid-19 | Biological | Jan 20, 2020 |
| Covid-19 Pandemic | Biological | Jan 20, 2020 |
| Hurricane Harvey | Hurricane | Aug 23, 2017 |
| Wildfires | Fire | Mar 14, 2008 |
| Extreme Wildfire Threat | Fire | Nov 27, 2005 |
| Hurricane Rita | Hurricane | Sep 23, 2005 |
| Hurricane Katrina Evacuation | Hurricane | Aug 29, 2005 |
| Hurricane Claudette | Hurricane | Jul 15, 2003 |
NOAA Storm Events Database (1996–2025)
Source: NOAA National Weather Service Storm Events Database.
| Type | Date | Damage |
|---|---|---|
| Flash Flood | May 13, 2023 | 0.00K |
| Flood | May 10, 2023 | 0.00K |
| Flash Flood | Oct 14, 2021 | 0.00K |
| Flash Flood | Jul 8, 2021 | 0.00K |
| Tropical Storm | Aug 26, 2017 | 0.00K |
| Flash Flood | Aug 21, 2016 | 0.00K |
| Flash Flood | Aug 14, 2016 | 0.00K |
| Flash Flood | Mar 21, 2015 | 0.00K |
| Flash Flood | May 15, 2015 | 0.00K |
| Flash Flood | May 26, 2014 | 0.00K |
Flash Flood — May 13, 2023
An upper level trough moved over a moist, unstable airmass and generated thunderstorms. Storms initially formed over the higher terrain in Mexico and moved across the Rio Grande into Texas. Some storms produced damaging wind gusts. Storms eventually congealed into a slow-moving line that produce locally heavy rain leading to flash flooding.
Flood — May 10, 2023
An upper level low generated thunderstorms in a warm, moist airmass. Some of these storms produced locally heavy rain leading to local flooding.
Flash Flood — Oct 14, 2021
A complicated weather pattern developed over South Central Texas when a dryline and cold front moved out of West Texas as an upper level low moved into the Central Plains. At the same time the remnants of Pacific Hurricane Pamela moved across northern Mexico. The airmass over the region was warm and moist with near record precipitable water values. This set up led to an excessive rain episode w...
Flash Flood — Jul 8, 2021
An area of low pressure over South Texas generated thunderstorms that moved into South Central Texas. Some of these storms produced heavy rain that led to flash flooding.
Tropical Storm — Aug 26, 2017
Hurricane Harvey moved onshore as a Category 4 hurricane over San Jose Island east of Rockport during the late evening of August 25th. Harvey moved inland entering southern DeWitt County during the morning of August 26th as a Category 1 hurricane. It continued to weaken as it moved farther inland eventually reaching south central Gonzales County as a tropical storm during the late evening of A...
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 Karnes County, Texas:
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 Karnes County, Texas 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.