Alert archive / Kansas / Severe Thunderstorm Warnings in 2026
Severe Thunderstorm Warning 217, NWS Topeka, KS
NWS Topeka, KS issued this severe thunderstorm warning at May 18, 2026, 7:20 PM CDT for Brown County, Nemaha County, Kansas. It was in force for 40 min. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- May 18, 2026, 7:20 PM CDT (00:20 UTC)
- Expired
- May 18, 2026, 8:00 PM CDT
- In force
- 40 min
- Issued by
- NWS Topeka, KS
- Area
- Storm-based polygon
- Damage threat
- Considerable
- Hail
- 0.88 in
- Wind
- 70.0 mph
Counties Brown County, KS, Nemaha County, KS
The radar
The Topeka radar (KTWX), 98 km from the middle of the area, began a volume at 00:19 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
The watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| May 18, 12:50 PM CDT | Tornado Watch | SPC | 7 hr |
The nearest sounding before it
Topeka, KS (KTOP), launched 00:00Z, 0.3 hours before the alert went out and 90 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 3248 J/kg
- Mixed-layer CIN
- -7 J/kg
- Mixed-layer LCL
- 1108 m above ground
- 0-6 km bulk shear
- 39 kt
- 0-1 km storm-relative helicity
- 209 m²/s²
- 0-3 km storm-relative helicity
- 370 m²/s²
- Significant tornado parameter
- 4.1
- Supercell composite
- 22.8
What forecasters said that day
The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Topeka, KS wrote its last area forecast discussion before this severe thunderstorm warning went out at May 18, 6:22 PM CDT, 58 minutes earlier. Its key messages:
- Severe thunderstorms becoming numerous early to mid afternoon today and spreading east to southeast this evening. Very large hail, damaging winds, and tornadoes all quite possible.
- Flash flooding remains a concern through tonight especially where heavy rain fall Sunday night.
- Gusty south winds on track for the next several hours in southwestern areas.
Area forecast discussion, May 18, 6:22 PM CDT, 58 minutes before
Area Forecast Discussion National Weather Service Topeka KS 622 PM CDT Mon May 18 2026 .KEY MESSAGES... - Severe thunderstorms becoming numerous early to mid afternoon today and spreading east to southeast this evening. Very large hail, damaging winds, and tornadoes all quite possible. - Flash flooding remains a concern through tonight especially where heavy rain fall Sunday night. - Gusty south winds on track for the next several hours in southwestern areas. && .DISCUSSION... Issued at 200 PM CDT Mon May 18 2026 Warm, humid airmass was surging north into central Kansas ahead of a cold front toward a nearly-stationary front just northeast of northeast Kansas with a modest upper wave just upstream. Instability of 3000 J/kg already commonplace in central Kansas at 17Z with 40-50 knots of deep-layer shear. Vectors for this layer remain close to parallel to the front so there is some uncertainty in how long storms can remain discrete, but some backing of low-level flow and otherwise good setup brings all severe hazards in play. Main area of concern over the next few hours is north-central Kansas with storms spreading east and southeast and becoming more widespread with time. Threats should turn more to wind versus strong tornado in eastern areas as mode shifts to more linear. Overall a more progressive system should keep storm residence somewhat limited, but areas that saw heavy rain Sunday night will not take much more rain to experience flash flooding and intense updrafts with PW values around 1.5 inches will bring quick rainfall. Storms push southeast before dawn with flash flooding threat falling off, though rivers and creeks may be high for a few more days. Surface winds Next few days continue to look benign with modified Canadian high pressure in place with cooler temperatures. Moisture return in the mid-levels supports at least moderate precipitation chances Thursday into Thursday night but instability remains modest. A more unstable airmass should return around the holiday weekend though forcing for ascent is not readily apparent. && .AVIATION /00Z TAFS THROUGH 00Z TUESDAY/... Issued at 611 PM CDT Mon May 18 2026 Line of strong/severe thunderstorms pushing through KMHX currently with continued eastward movement of main convective line. TEMPO group through 01-05z for KTOP and KFOE for TSRA with viz 1SM and MVFR/IFR conditions. Conditions improve from west to east later in forecast period, around 05z for western TAF sites; 10z for eastern TAF sites. && .TOP WATCHES/WARNINGS/ADVISORIES... Flood Watch through Tuesday morning for KSZ008-KSZ009-KSZ010-KSZ011- KSZ012-KSZ020-KSZ021-KSZ022-KSZ023-KSZ024-KSZ026-KSZ034-KSZ035- KSZ036-KSZ037-KSZ038-KSZ039-KSZ040-KSZ054-KSZ055-KSZ056-KSZ058- KSZ059. Wind Advisory until 9 PM CDT this evening for KSZ035-KSZ036-KSZ037- KSZ038-KSZ054. && DISCUSSION...Poage AVIATION...JTW
Hazardous weather outlook, May 18, 1:38 PM CDT, 5 hours 42 minutes before
Hazardous Weather Outlook National Weather Service Topeka KS 138 PM CDT Mon May 18 2026 KSZ008>012-020>024-026-034>040-054>056-058-059-191845- Republic-Washington-Marshall-Nemaha-Brown-Cloud-Clay-Riley- Pottawatomie-Jackson-Jefferson-Ottawa-Dickinson-Geary-Morris- Wabaunsee-Shawnee-Douglas-Lyon-Osage-Franklin-Coffey-Anderson- 138 PM CDT Mon May 18 2026 This Hazardous Weather Outlook is for portions of central Kansas, east central Kansas, north central Kansas, and northeast Kansas. .DAY ONE...This Afternoon and Tonight South winds sustained around 25 MPH with gusts around 45 MPH are forecast for locations southwest of a line from Abilene to Alma to Emporia in to the evening. Severe thunderstorms are expected through the middle of the afternoon in north central Kansas. These storms may form into a line as they move east and southeast late this afternoon and this evening. Very large hail, damaging wind gusts, and a few strong tornadoes are the main hazards. Localized flooding is also a concern, especially if storms persist over areas that received heavy rain Sunday night. A Flood Watch remains in effect through 7 AM Tuesday morning. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Spotters will likely be needed this afternoon or tonight. && More detailed information can be found at: www.weather.gov/media/top/DssPacket.pdf
In the hours before
Local storm report, May 18, 6:34 PM CDT, 46 minutes before
Preliminary Local Storm Report
National Weather Service Topeka KS
634 PM CDT Mon May 18 2026
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0622 PM Tstm Wnd Gst Ogden 39.11N 96.71W
05/18/2026 E65 MPH Riley KS Public
&&
STLocal storm report, May 18, 6:40 PM CDT, 40 minutes before
Preliminary Local Storm Report
National Weather Service Topeka KS
640 PM CDT Mon May 18 2026
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0628 PM Tstm Wnd Gst 3 N Manhattan 39.23N 96.57W
05/18/2026 M67 MPH Riley KS Public
&&
STLocal storm report, May 18, 6:41 PM CDT, 39 minutes before
Preliminary Local Storm Report
National Weather Service Topeka KS
641 PM CDT Mon May 18 2026
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0641 PM Tstm Wnd Gst 7 NNE Manhattan 39.27N 96.52W
05/18/2026 M59 MPH Pottawatomie KS Public
Personal weather station.
&&
STLocal storm report, May 18, 6:50 PM CDT, 30 minutes before
Preliminary Local Storm Report
National Weather Service Topeka KS
650 PM CDT Mon May 18 2026
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0649 PM Tstm Wnd Gst 2 SW Louisville 39.23N 96.34W
05/18/2026 M78 MPH Pottawatomie KS Public
Measured on a personal weather station.
&&
STLocal storm report, May 18, 6:53 PM CDT, 27 minutes before
Preliminary Local Storm Report
National Weather Service Topeka KS
653 PM CDT Mon May 18 2026
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0622 PM Tstm Wnd Gst Ogden 39.11N 96.71W
05/18/2026 E65 MPH Riley KS Public
0628 PM Tstm Wnd Gst 3 N Manhattan 39.23N 96.57W
05/18/2026 M67 MPH Riley KS Public
&&Local storm report, May 18, 7:20 PM CDT, 0 minutes before
Preliminary Local Storm Report
National Weather Service Topeka KS
720 PM CDT Mon May 18 2026
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0712 PM Hail White City 38.80N 96.74W
05/18/2026 M0.88 Inch Morris KS Public
&&
SMBThe office that day
Everything else NWS Topeka, KS issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 18, 7:07 PM CDT | Areal Flood Advisory | TOP | Marshall, Nemaha | 2 hr |
| May 18, 7:17 PM CDT | Flash Flood Warning | TOP | Geary, Pottawatomie, Riley | 3 hr |
| May 18, 7:22 PM CDT | Tornado Warning | TOP | Jackson | 23 min |
| May 18, 7:27 PM CDT | Severe Thunderstorm Warning | TOP | Brown, Jackson, Jefferson, Nemaha, Shawnee | 33 min |
| May 18, 7:28 PM CDT | Severe Thunderstorm Warning | TOP | Geary, Jackson, Pottawatomie, Riley, Shawnee, Wabaunsee | 36 min |
| May 18, 7:31 PM CDT | Severe Thunderstorm Warning | TOP | Geary, Lyon, Morris, Wabaunsee | 44 min |
| May 18, 7:41 PM CDT | Flash Flood Warning | TOP | Geary, Riley, Wabaunsee | 3 hr |
| May 18, 7:47 PM CDT | Tornado Warning | TOP | Lyon, Morris, Wabaunsee | 28 min |
| May 18, 7:49 PM CDT | Areal Flood Advisory | TOP | Pottawatomie, Wabaunsee | 3 hr |
| May 18, 7:53 PM CDT | Severe Thunderstorm Warning | TOP | Coffey, Jefferson, Lyon, Osage, Shawnee, Wabaunsee | 52 min |
| May 18, 7:56 PM CDT | Tornado Warning | TOP | Lyon, Wabaunsee | 19 min |
| May 18, 8:00 PM CDT | Severe Thunderstorm Warning | TOP | Coffey, Franklin, Lyon, Osage, Wabaunsee | 45 min |
| May 18, 8:08 PM CDT | Tornado Warning | TOP | Osage, Shawnee, Wabaunsee | 22 min |
| May 18, 8:28 PM CDT | Severe Thunderstorm Warning | TOP | Douglas, Franklin, Jefferson, Osage, Shawnee | 47 min |
| May 18, 8:36 PM CDT | Severe Thunderstorm Warning | TOP | Lyon | 39 min |
| May 18, 9:11 PM CDT | Areal Flood Advisory | TOP | Lyon | 114 min |
| May 18, 9:11 PM CDT | Severe Thunderstorm Warning | TOP | Franklin | 22 min |
| May 18, 9:13 PM CDT | Severe Thunderstorm Warning | TOP | Coffey, Lyon | 47 min |
| May 18, 9:45 PM CDT | River Flood Warning | TOP | Marshall | 41 hr |
| May 18, 9:56 PM CDT | Special Weather Statement | TOP | Coffey | 34 min |
| May 18, 10:18 PM CDT | Severe Thunderstorm Warning | TOP | Coffey, Lyon | 42 min |
| May 18, 10:57 PM CDT | Severe Thunderstorm Warning | TOP | Anderson, Coffey | 33 min |
| May 18, 11:07 PM CDT | Severe Thunderstorm Warning | TOP | Anderson, Coffey | 23 min |
| May 18, 11:25 PM CDT | Severe Thunderstorm Warning | TOP | Anderson, Franklin | 20 min |
| May 18, 11:37 PM CDT | Areal Flood Advisory | TOP | Anderson, Coffey | 3 hr |
Nearby
Severe Thunderstorm Warnings in Kansas, 2026Every severe thunderstorm warning in 2026
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.