St. Tammany Parish

Every recorded tornado

1. Injuries and deaths are for the tornado’s whole path, which may extend beyond the county. Deaths recorded within St. Tammany Parish: 0.
2. Weak tornadoes were under-recorded before Doppler radar coverage became national in the early 1990s, so earlier decades read low. Ratings use the Fujita scale before February 2007 and the Enhanced Fujita scale after.

Storm Prediction Center severe weather database, 1950 to 2025.

Every storm within 100 miles

1. Tropical storms and hurricanes (34 kt or more, still tropical) at closest approach. Post-tropical remnants with gale-force winds are listed but not counted. Direct: track within 50 miles; near: within 100 miles. Distance is measured to the county boundary for counties and to the city centre for cities, using positions interpolated hourly between HURDAT2 fixes.

National Hurricane Center HURDAT2, 1851 to 2025.

Every large fire

1. Large fires mapped by the Monitoring Trends in Burn Severity program since 1984: 1,000 acres or more in the West, 500 or more in the East. Prescribed burns are excluded. Acres here are the part of each perimeter inside this place.

Monitoring Trends in Burn Severity (USGS and U.S. Forest Service), 1984 to 2026.

Smoke overhead

1. A smoke day is a date on which a smoke plume traced by NOAA Hazard Mapping System analysts from satellite imagery covered this place's point (the county's population centre or the city centre). Counts here are of medium or heavy smoke. Since 2018 analysts have often drawn light smoke as one area over most of the continent, so light-smoke counts are not comparable from year to year. The plumes show smoke anywhere in the air above, not air quality at the ground, and smoke hidden by cloud is missed.

NOAA Hazard Mapping System smoke analysis, 2011 to 2026, retrieved October 30, 2026.

Claims by ZIP code

This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).

OpenFEMA NFIP Redacted Claims v3, refreshed August 4, 2026. NOAA Storm Events through 2026.

River crests

River gauges

1. Crests are the highest and the recent crests the National Weather Service lists for each river gauge in the county that has a flood stage, not every flood. Flood categories use each gauge's current flood stages; crests from before levees, dams or channel changes may not be comparable. Crests measured on an old datum are left out of the rankings.

NOAA National Water Prediction Service gauge records, retrieved October 30, 2026.

1. The Palmer Drought Severity Index is computed by NOAA each month from the county's average temperature and precipitation, relative to the county's own climate. Zero is normal; -3 or lower is severe drought and -4 or lower extreme drought. It describes the long-term balance of moisture, not water supply or crop losses.

NOAA NCEI nClimDiv county Palmer Drought Severity Index, 1895 to September 2026, issued October 6, 2026.

1. Earthquakes of magnitude 2.5 or more in the USGS Comprehensive Catalog since 1900. Within 50 miles means the epicentre lies within 50 miles of the county boundary (or inside the county).
2. Small earthquakes were under-recorded before the modern seismic networks of the 1970s and are still missed in remote areas, so early decades read low. Magnitudes are as the catalogue reports them and mix scales (moment, local and body-wave).

USGS ANSS Comprehensive Earthquake Catalog, 1900 to present, retrieved October 30, 2026.

More event types since 1996

Costliest events since 1996

1. Aug 29, 2005Storm Surge/Tide, St. Tammany$3.0 billion
   National Weather Service narrative

   Storm surge damage in southeast Louisiana, especially in the New Orleans area and the coastal parishes, was catastrophic. Hurricane protection levees and floodwalls were overtopped and/or breached resulting in widespread and deep flooding of homes and businesses. Much of Orleans and Plaquemines Parishes and nearly all of St. Bernard Parish were flooded by storm surge. Approximately 80 percent of the city of New Orleans was flooded. Thousands of people were stranded by the flood waters in homes and buildings and on rooftops for several days and had to be rescued by boat and helicopter. In Jefferson Parish, levees were not compromised, however many homes were flooded by either heavy…

2. Aug 28, 2005Hurricane (Typhoon), St. Tammany$2.5 billion
   National Weather Service narrative

   Hurricane Katrina was one of the strongest and most destructive hurricanes on record to impact the coast of the United States. It will likely be recorded as one the worst natural disaster in the history of the United States to date resulting in catastrophic damage and numerous casualties in southeast Louisiana and along the Mississippi coast. Damage and casualties resulting from Hurricane Katrina extended as far east as Alabama and the panhandle of Florida. Katrina developed from a tropical depression southeast of the Bahamas on August 24th. After moving through the Bahamas as a tropical storm, Katrina strengthened to a category 1 hurricane prior to landfall in south Florida…

3. Aug 29, 2021Hurricane (Typhoon), Northwest St. Tammany Parish$500 million
   National Weather Service narrative

   The parish suffered significant wind damage, with the greatest impacts across the western half of the parish. Thousands of trees were downed across the parish, with widespread minor to moderate damage to structures as well. Most structural damage was in the form of roof damage or other fascia damage, however, some structures suffered major damage due to falling trees. There were four indirect fatalities in the parish: one due to trauma from falling off a roof while making repairs, one due to lack of oxygen during the power outage, one due to excessive heat, and one due to an alligator attack.

4. Aug 28, 2021Storm Surge/Tide, Northwest St. Tammany Parish$100 million
   National Weather Service narrative

   Storm surge topped the seawall in Mandeville, flooding several blocks of the lakefront neighborhood. Nearly 2 feet of water covered much of Madisonville, and at least one home took in water. Estimated peak inundation was 5-7 feet.

5. Aug 29, 2021Hurricane (Typhoon), Southeast St. Tammany Parish$100 million
   National Weather Service narrative

   The parish suffered significant wind damage, with the greatest impacts across the western half of the parish. Thousands of trees were downed across the parish, with widespread minor to moderate damage to structures as well. Most structural damage was in the form of roof damage or other fascia damage, however, some structures suffered major damage due to falling trees. Additional wind damage occurred across the east side of the parish, and there were 2 confirmed tornadoes in Slidell.

6. Aug 28, 2012Storm Surge/Tide, St. Tammany$42.8 million
   National Weather Service narrative

   Isaac entered the Gulf of Mexico as a tropical storm on August 26, moving northwest after crossing Haiti, Cuba and the Florida Straits. Isaac strengthened into a hurricane on the morning of the 28th when it was 75 miles south-southeast of the mouth of the Mississippi River. Isaac made landfall in Plaquemines Parish as a Category 1 Hurricane near Southwest Pass of the Mississippi River on the evening of the 28th. A second landfall occurred near Port Fourchon the following morning. The storm weakened to a tropical storm on the afternoon of the 29th about 50 miles west southwest of New Orleans, and weakened further to a tropical depression on the afternoon of the 30th near Monroe,…

7. Oct 28, 2020Hurricane (Typhoon), St. Tammany$15.0 million
   National Weather Service narrative

   Zeta produced tropical storm force winds and likely some hurricane force wind gusts which led to widespread damage to trees, power lines and some power poles across the parish. At the peak, roughly 60 percent of the parish was without power.

8. Aug 28, 2021Storm Surge/Tide, Southeast St. Tammany Parish$10.0 million
   National Weather Service narrative

   Storm surge flooding pushed water into some homes and cut off low lying portions of Slidell - including the Palm Lake. Estimated peak inundation was 5-7 feet.

9. Sep 23, 2005Storm Surge/Tide, St. Tammany$8.6 million
   National Weather Service narrative

   Hurricane Rita produced extensive storm surge flooding across coastal areas of southern Terrebonne, southern Lafourche, and southern Jefferson Parishes where numerous homes and businesses were flooded. Some of the most substantial damage occurred in southern Terrebone Parish where storm surge of 5 to 7 feet above normal overtopped or breached local drainage levees inundating many small communities. Newspaper accounts indicated approximately 10,000 structures were flooded in Terrebonne Parish. Lafitte and other coummnities in lower Jefferson Parish also suffered extensive storm surge flooding. Storm surge flooding also occurred in some areas adjacent to Lakes Pontchartrain and…

10. Sep 25, 2002Tropical Storm, St. Tammany$6.4 million
    National Weather Service narrative

    Tropical Storm Isidore moved steadily northward across the central Gulf of Mexico on September 24 and September 25, 2002 before moving ashore near Grand Isle early on the morning on Thursday, September 26, 2002. The tropical storm moved steadily north across southeast Louisiana and by the afternoon of September 26 was located in central Mississippi downgraded to a tropical depression. Tropical Storm Isidore had a large circulation with tropical storm force winds extending several hundreds of miles from its center. Prior to moving onto the Yucatan Peninsula earlier in the week and weakening, Isidore was classified as a major hurricane. Swells from the distant hurricane resulted in…

1. Storm Events records before 1996 cover only tornadoes, thunderstorm wind and hail. Damage figures are as reported by the National Weather Service at the time, not adjusted for inflation.

NOAA NCEI Storm Events Database, 1950 to 2026, issued October 26, 2026.

All-time high

108°FAug 26, 2023

All-time low

8°FJan 22, 2025

Warmest night

86°FAug 10, 2023

Coldest day

32°FFeb 4, 1996

Wettest day

11.36 inMay 10, 1995

Snowiest day

5.0 inJan 21, 2025

Hottest year

2023mean 71.3°F

Coldest year

2014mean 66.4°F

Wettest year

199193.07 in

Driest year

200038.48 in

Station Slidell Airport (USW00053865), 25 ft elevation, 8.8 miles from the population centre. Daily records from 1994 to October 26, 2026; 99.6% of days in the last 30 years are complete. Records at a single station can differ from a city’s official threaded record, which may combine several stations.

NOAA NCEI Global Historical Climatology Network Daily.

This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).

OpenFEMA Disaster Declarations Summaries, retrieved October 30, 2026. Statewide declarations are not listed.

Neighbouring counties

• Tornadoes NOAA Storm Prediction Center severe weather database, through 2025.
• Tropical cyclones NOAA National Hurricane Center HURDAT2 (Atlantic; Northeast and Central Pacific), through 2025.
• Wildfire USGS/USFS Monitoring Trends in Burn Severity, through 2026.
• Storm events NOAA NCEI Storm Events Database, through 2026.
• Flood insurance OpenFEMA NFIP Redacted Claims v3, refreshed August 4, 2026.
• Declarations OpenFEMA Disaster Declarations Summaries v2, retrieved October 30, 2026.
• Weather records NOAA NCEI Global Historical Climatology Network Daily, station USW00053865.
• River crests NOAA National Weather Service, National Water Prediction Service river gauges, retrieved October 30, 2026.
• Drought NOAA NCEI nClimDiv county Palmer Drought Severity Index, through September 2026.
• Smoke NOAA NESDIS Hazard Mapping System smoke analysis, retrieved October 30, 2026.
• Earthquakes USGS ANSS Comprehensive Earthquake Catalog (ComCat), retrieved October 30, 2026.

Joins, thresholds and known limits are set out in the methodology. Found an error? Report it. Page built October 30, 2026.