Merriam

Every recorded tornado

1. Injuries and deaths are for the tornado’s whole path, which may extend beyond this area.
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.

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.

Flood insurance figures are for Johnson County, the county that contains Merriam.

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 in Johnson County, the county that contains Merriam.

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.

The drought index is for Johnson County, the county that contains Merriam.

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 city centre.
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. Oct 4, 1998Flash Flood$8.0 million
   National Weather Service narrative

   Thunderstorms on the evening of October 4th produced very heavy rainfall resulting in major flash flooding over the Kansas counties of the Kansas City metropolitan area. Up to 3 to 5 inches of rain fell in a three hour period between 6:00 PM and 9:00 PM CDT. In Lenexa, KS, over 5 inches of rain fell between 7:00 PM and 8:15 PM. The heavy rainfall with these evening thunderstorms fell on top of an already rain soaked soil from 1 to 3 inches of rain that had fallen over the region earlier in the day. Rain also fell on 6 of the 7 days during the week prior to the flash flood.In Johnson County, a 27 year old male was killed in Lenexa when his car was swept of the road near the…

2. Jan 30, 2002Ice Storm, Johnson$5.0 million
   National Weather Service narrative

   A long-lived major ice and snow storm blasted much of eastern Kansas, January 29th through January 31st. Ice accumulations of 1 to 2 inches were observed with snow accumulations of 6 to 10 inches in Atchison and Doniphan counties. The results of the storm were devasting to many communities. A tremendous amount of people were without power for extended periods of times, due to downed trees and tree limbs crippling power supplies in the affected areas.

3. Jun 28, 1999Flash Flood$500,000
   National Weather Service narrative

   Several homes were flooded in Olathe and Mission Hills, and fire and rescue units responded to 74 emergency calls during the morning of June 28. Unofficial reports were received of 4 inches of rain in an hour, and a storm total of 7.8 inches was received at 131st and Kenneth Road. Near Stanley, flood waters from the Blue River were over the 151st Street bridge. Sections of Interstate 35 were closed due to high water.

4. Mar 6, 2017Thunderstorm Wind$500,000
   National Weather Service narrative

   On the evening of March 6, a squall line with damaging winds moved through the Johnson County Executive Airport, and produced significant damage to hangars and aircraft enclosed in the hangars. Several planes were flipped after the building shredded apart by the strong straight line winds. NWS survey inspected the site and due to damage being spread in a unidirectional fashion the cause of the damage was deemed to be straight line winds ranging between 80 and 90 mph.

5. Oct 23, 1996Heavy Snow, Johnson$500,000
   National Weather Service narrative

   A record setting early season snowfall knocked out power to an estimated 50,000 customers. The heavy wet snow also knocked over numerous trees which were still foliage filled and downed power lines. Property damage was estimated at a half a million dollars.Snowfall amounts ranged from 2 inches at Desoto, to 6 inches at Stanley and 8 inches at Shawnee.

6. Aug 27, 2004Flash Flood$500,000
   National Weather Service narrative

   4 to 6 inches of rain in a short period of time caused the northbound ramp to Southwest Trafficway to close. Water rescues were conducted and several homes and businesses suffered flooding.

7. Sep 11, 2000Lightning$325,000
   National Weather Service narrative

   Lightning sparked a house fire which caused $325,000 in damage to the house and its contents.

8. Mar 12, 2006Hail$250,000
   National Weather Service narrative

   Numerous roofs and cars damaged by the hail.

9. Jun 26, 2002Thunderstorm Wind$250,000
   National Weather Service narrative

   Thunderstorm winds ripped off portions of a roof on a VFW building and a Toys "R" Us building. Numerous trees were uprooted. Tractor trailer rigs were overturned. Power lines were also downed and power poles were snapped in two. The downtown jail reported damage.

10. Aug 7, 1999Thunderstorm Wind$200,000
    National Weather Service narrative

    Thunderstorms developed over eastern Kansas in the late afternoon and early evening hours of August 7, and moved eastward into southwestern sections of the Kansas City metro area. The hardest hit area was Olathe, where restaurant signs were damaged, part of the roof was torn off a strip mall, and a building and several vehicles were damaged at an auto dealership. Another storm downed trees and power lines about an hour later in DeSoto and Roeland Park.

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

113°FAug 14, 1936

All-time low

−19°FDec 22, 1989

Warmest night

89°FJul 10, 1980

Coldest day

−4°FDec 22, 1989

Wettest day

7.45 inAug 15, 1969

Snowiest day

11.8 inJan 18, 1962

Hottest year

2012mean 61.2°F

Coldest year

1951mean 53.5°F

Wettest year

196160.25 in

Driest year

198819.17 in

Station Kansas City Dwtn Airport (USW00013988), 742 ft elevation, 9.5 miles from the city centre. Daily records from 1934 to October 27, 2026; 98.9% 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.

Declarations for Johnson County.

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.

• 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 USW00013988.
• 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.