Alert archive / Kansas / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 331, NWS Topeka, KS

June 20, 2026Brown County, Kansas

NWS Topeka, KS issued this severe thunderstorm warning at Jun 20, 2026, 11:05 PM CDT for Brown County, Kansas. It was in force for 25 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jun 20, 2026, 11:05 PM CDT (04:05 UTC)
Expired
Jun 20, 2026, 11:30 PM CDT
In force
25 min
Issued by
NWS Topeka, KS
Area
Storm-based polygon
Damage threat
Considerable
Hail
0.75 in
Wind
70.0 mph

County Brown County, KS

The radar

The Topeka radar (KTWX), 115 km from the middle of the area, began a volume at 04:07 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Topeka, KS (KTOP), launched 00:00Z, 4.1 hours before the alert went out and 94 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.

Skew-T log-pSkew-T log-p diagram, Topeka, KS at 00:00Z on 2026-06-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 516 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Topeka, KS at 00:00Z on 2026-06-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 54 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
516 J/kg
Mixed-layer CIN
-36 J/kg
Mixed-layer LCL
1348 m above ground
0-6 km bulk shear
51 kt
0-1 km storm-relative helicity
54 m²/s²
0-3 km storm-relative helicity
159 m²/s²
Significant tornado parameter
0.3
Supercell composite
4.9

Open this sounding in Storm Lab

The text

As transmitted.

463 
WUUS53 KTOP 210405
SVRTOP
KSC013-210430-
/O.NEW.KTOP.SV.W.0331.260621T0405Z-260621T0430Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Topeka KS
1105 PM CDT Sat Jun 20 2026

The National Weather Service in Topeka has issued a

* Severe Thunderstorm Warning for...
  Eastern Brown County in northeastern Kansas...

* Until 1130 PM CDT.

* At 1104 PM CDT, a severe thunderstorm was located over Hiawatha,
  moving east at 25 mph.

  HAZARD...70 mph wind gusts and penny size hail.

  SOURCE...Radar indicated.  A 68 mph wind gust was reported near 
           Hiawatha. 

  IMPACT...Expect considerable tree damage. Damage is likely to 
           mobile homes, roofs, and outbuildings.

* Locations impacted include...
  Hiawatha, Robinson, Powhattan, and Willis.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3991 9534 3967 9534 3976 9564 3993 9558
TIME...MOT...LOC 0404Z 283DEG 22KT 3983 9552 

THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...OBSERVED
MAX WIND GUST...70 MPH

$$

Prieto
2 follow-up statements
969 
WWUS53 KTOP 210414
SVSTOP

Severe Weather Statement
National Weather Service Topeka KS
1114 PM CDT Sat Jun 20 2026

KSC013-210430-
/O.CON.KTOP.SV.W.0331.000000T0000Z-260621T0430Z/
Brown-
1114 PM CDT Sat Jun 20 2026

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1130 PM CDT
FOR EASTERN BROWN COUNTY...

At 1113 PM CDT, a severe thunderstorm was located over Robinson,
moving east at 25 mph.

HAZARD...70 mph wind gusts and penny size hail.

SOURCE...Radar indicated.

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings.

Locations impacted include...
Hiawatha, Robinson, and Willis.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3991 9534 3967 9534 3974 9558 3993 9553
TIME...MOT...LOC 0413Z 283DEG 22KT 3982 9544 

THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH

$$

Prieto
536 
WWUS53 KTOP 210425
SVSTOP

Severe Weather Statement
National Weather Service Topeka KS
1125 PM CDT Sat Jun 20 2026

KSC013-210435-
/O.EXP.KTOP.SV.W.0331.000000T0000Z-260621T0430Z/
Brown-
1125 PM CDT Sat Jun 20 2026

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN BROWN COUNTY WILL
EXPIRE AT 1130 PM CDT...

The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However, heavy
rain is still possible with this thunderstorm.

&&

LAT...LON 3991 9534 3967 9534 3974 9558 3993 9553
TIME...MOT...LOC 0425Z 283DEG 22KT 3981 9536 

$$

Prieto

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 Jun 20, 6:16 PM CDT, 4 hours 49 minutes earlier. Its key messages:

  • Thunderstorm chances increase this evening, then become likely overnight into Sunday morning (60-90%). Heavy rainfall with flooding and severe storms with damaging winds are the primary concerns, although hail to quarter size and a brief tornado cannot be ruled out.
  • Storms may linger in east central KS Sunday late morning and afternoon (20-50% chance).
  • Temperatures stay a bit cooler than average through next week alongside periodic storm chances.
Area forecast discussion, Jun 20, 6:16 PM CDT, 4 hours 49 minutes before
Area Forecast Discussion
National Weather Service Topeka KS
616 PM CDT Sat Jun 20 2026

.KEY MESSAGES...

- Thunderstorm chances increase this evening, then become likely
overnight into Sunday morning (60-90%). Heavy rainfall with flooding
and severe storms with damaging winds are the primary concerns,
although hail to quarter size and a brief tornado cannot be ruled
out.

- Storms may linger in east central KS Sunday late morning and
afternoon (20-50% chance).

- Temperatures stay a bit cooler than average through next week
alongside periodic storm chances.

&&

.DISCUSSION...
Issued at 248 PM CDT Sat Jun 20 2026

Surface low pressure has been deepening in eastern CO in response to
an upper trough traversing out of the Great Basin and Intermountain
West region. The surface warm front has started to slowly lift north
through the CWA this morning, likely placed along or just south of
the I-70 corridor based on 19z observations and visible satellite.
Meanwhile, a subtle perturbation rounding the low-amplitude ridge
overhead has helped to trigger elevated supercells in central
Nebraska, which have been following the MUCAPE gradient this morning
into the early afternoon. This trajectory would favor these storms
staying just north of the KS/NE border through the afternoon, which
is what more recent HRRR runs have shown as well.

Our main focus remains on this evening and overnight, and we should
stay quiet until then assuming the above scenario pans out.
Shortwave energy from the aforementioned upper trough looks to eject
across the High Plains this evening and eventually across the MO
River Valley by Sunday morning. This feature will lead to the
development of storms in western KS this evening that will
eventually evolve into an MCS. There is still a bit of uncertainty
in whether any discrete storms can develop along the warm front
earlier this evening (around 02-03z) ahead of the MCS, which looks
to move into our area closer to midnight. If these discrete cells
can develop, this would present more of a threat for hail or
tornadoes than anything later on, as sfc winds are more backed at
this time. They become more veered with the approach of the MCS. All
the while, the strengthening LLJ this evening will continue to pump
in more moisture and provide the lift needed to maintain a severe
weather risk as storms enter north central KS. Damaging winds are
the main severe hazard with a lower risk for hail or a brief spin-up
tornado. Flooding is the other primary concern with storms
overnight. In addition to the MCS coming from western KS, CAMs have
shown more rounds of rainfall with clusters and lines of storms
coming southeastward out of Nebraska. This setup could lead to some
locations getting hit by repeated rounds of heavy rainfall if they
go over the same places again and again. While it is uncertain
exactly where this might happen and where the highest amounts could
be as a result, several CAM solutions show pockets of 3-6" through
Sunday morning. The HREF has a subtle signal for intense rainfall
rates, and more specifically, the HRRR has been indicating 2-3"/hr
rainfall rates may be possible in localized areas. Overall, most
locations can expect to see 1-3", but some will probably see those
locally higher amounts mentioned, which presents a concern for flash
flooding and river flooding. Have made no changes to the going Flood
Watch.

Some of the storms and heavy rain may linger into mid/late morning
in east central KS before it eventually moves out and subsidence
takes over behind the upper wave. From there, the chance of any
redeveloping storms in the afternoon and evening will be highly
dependent on the location of any outflow boundary the morning
convection lays out. That or the synoptic cold front could be the
focus for afternoon storms by that point. Current CAMs have this
activity mainly along and south of I-35 before it pushes south later
in the evening. If storms develop before the boundary moves south,
they could have large hail or damaging winds with them.

Getting into the next work week, our area finds itself in a
northwest flow pattern aloft with ridging parked over the
southwestern US. Embedded perturbations rounding the ridge bring
more chances for storms at times through the next week, but
predictability of the timing and placement of these waves tends to
be lower at this range, so PoPs are generally below 50% at any
particular time period. Temperatures look to hold slightly cooler
than average through the week with highs in the upper 70s to low 80s
and lows in the upper 50s to low 60s.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 616 PM CDT Sat Jun 20 2026

Main changes to the forecast were adjustments in timing of TSRA
expected to develop northwest of terminals, tracking southeast
and entering KMHK as early as 05Z and KTOP/KFOE near 06Z. Tempo
groups were kept where intensity of storms are highest and several
rounds of TSRA where conditions may briefly improve. Low end MVFR cigs
follow behind the main area of storms aft 14Z with gradual improvement
to VFR as the fropa and drier air occurs in the 18-20Z timeframe.

&&

.TOP WATCHES/WARNINGS/ADVISORIES...
Flood Watch through Sunday afternoon for KSZ008-KSZ009-KSZ010-
KSZ011-KSZ012-KSZ020-KSZ021-KSZ022-KSZ023-KSZ024-KSZ026-KSZ034-
KSZ035-KSZ036-KSZ037-KSZ038-KSZ039-KSZ040.
Flood Watch through Sunday evening for KSZ054-KSZ055-KSZ056-KSZ058-
KSZ059.

&&

DISCUSSION...Picha
AVIATION...Prieto
Hazardous weather outlook, Jun 20, 2:52 PM CDT, 8 hours 13 minutes before
Hazardous Weather Outlook
National Weather Service Topeka KS
252 PM CDT Sat Jun 20 2026

KSZ008>012-020>024-026-034>040-054>056-058-059-212000-
Republic-Washington-Marshall-Nemaha-Brown-Cloud-Clay-Riley-
Pottawatomie-Jackson-Jefferson-Ottawa-Dickinson-Geary-Morris-
Wabaunsee-Shawnee-Douglas-Lyon-Osage-Franklin-Coffey-Anderson-
252 PM CDT Sat Jun 20 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

Thunderstorms are likely late tonight, especially through the
overnight hours. Primary hazards are damaging winds and heavy
rainfall leading to flooding, although large hail and a brief
tornado cannot be ruled out.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

Severe storms may continue into Sunday morning across east central
KS, along with the potential for heavy rainfall. A few additional
storms may redevelop Sunday afternoon and evening along and south
of Interstate 35.

.SPOTTER INFORMATION STATEMENT...

Spotters may be needed tonight.

In the hours before

Special weather statement, Jun 20, 6:14 PM CDT, 4 hours 51 minutes before
Special Weather Statement
National Weather Service Topeka KS
614 PM CDT Sat Jun 20 2026

KSZ010-202345-
Marshall-
614 PM CDT Sat Jun 20 2026

...A STRONG THUNDERSTORM WILL IMPACT NORTH CENTRAL MARSHALL COUNTY
THROUGH 645 PM CDT...

At 613 PM CDT, Doppler radar was tracking a strong thunderstorm near
Wymore, moving southeast at 40 mph.

HAZARD...Strong wind gusts of 50 to 55 mph and nickel size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Hail damage to outdoor objects and
         vegetation is possible.

Locations impacted include...
Summerfield and Oketo.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 4000 9629 3987 9645 4000 9675
TIME...MOT...LOC 2313Z 294DEG 33KT 4007 9665

MAX HAIL SIZE...0.88 IN
MAX WIND GUST...55 MPH

Prieto
Special weather statement, Jun 20, 10:33 PM CDT, 32 minutes before
Special Weather Statement
National Weather Service Topeka KS
1033 PM CDT Sat Jun 20 2026

KSZ011-012-210400-
Brown-Nemaha-
1033 PM CDT Sat Jun 20 2026

...A STRONG THUNDERSTORM WILL IMPACT EAST CENTRAL NEMAHA AND CENTRAL
BROWN COUNTIES THROUGH 1100 PM CDT...

At 1033 PM CDT, Doppler radar was tracking a strong thunderstorm over
Fairview, moving southeast at 30 mph.

HAZARD...Strong wind gusts of 50 to 55 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to vegetation is possible.

Locations impacted include...
Hiawatha, Sabetha, Horton, Fairview, Robinson, Morrill, Powhattan,
Hamlin, Willis, and Kickapoo Reservation.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 3998 9572 3983 9537 3965 9553 3965 9562
      3979 9587
TIME...MOT...LOC 0333Z 304DEG 26KT 3984 9573

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...55 MPH

Prieto
Special weather statement, Jun 20, 10:45 PM CDT, 20 minutes before
Special Weather Statement
National Weather Service Topeka KS
1045 PM CDT Sat Jun 20 2026

KSZ009-021-210415-
Clay-Washington-
1045 PM CDT Sat Jun 20 2026

...STRONG THUNDERSTORMS WILL IMPACT SOUTHERN WASHINGTON AND
NORTHEASTERN CLAY COUNTIES THROUGH 1115 PM CDT...

At 1045 PM CDT, Doppler radar was tracking a cluster of strong
thunderstorms near Linn, moving east at 25 mph.

HAZARD...Strong wind gusts of 50 to 55 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Washington, Clifton, Linn, Greenleaf, Barnes, Morrowville, and
Palmer.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

A Severe Thunderstorm Watch remains in effect until 300 AM CDT for
north central Kansas.

&&

LAT...LON 3974 9681 3971 9681 3957 9691 3957 9696
      3952 9696 3955 9728 3989 9729
TIME...MOT...LOC 0345Z 286DEG 23KT 3969 9714

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...55 MPH

Prieto
Special weather statement, Jun 20, 10:57 PM CDT, 8 minutes before
Special Weather Statement
National Weather Service Topeka KS
1057 PM CDT Sat Jun 20 2026

KSZ012-210430-
Brown-
1057 PM CDT Sat Jun 20 2026

...A STRONG THUNDERSTORM WILL IMPACT EASTERN BROWN COUNTY THROUGH
1130 PM CDT...

At 1057 PM CDT, Doppler radar was tracking a strong thunderstorm near
Hiawatha, moving east at 25 mph.

HAZARD...Strong wind gusts of 50 to 55 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Hiawatha, Everest, Robinson, Powhattan, Hamlin, and Willis.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 3990 9534 3965 9534 3965 9536 3975 9568
      3993 9564
TIME...MOT...LOC 0357Z 283DEG 22KT 3983 9558

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...55 MPH

Prieto

The office that day

Everything else NWS Topeka, KS issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 20, 9:27 PM CDTSevere Thunderstorm WarningTOPRepublic33 min
Jun 20, 9:50 PM CDTSevere Thunderstorm WarningTOPRepublic, Washington40 min
Jun 20, 9:55 PM CDTTornado WarningTOPRepublic20 min
Jun 20, 10:19 PM CDTAreal Flood AdvisoryTOPMarshall, Nemaha9 hr
Jun 20, 10:33 PM CDTSpecial Weather StatementTOPBrown27 min
Jun 20, 10:45 PM CDTSpecial Weather StatementTOPWashington30 min
Jun 20, 10:57 PM CDTSpecial Weather StatementTOPBrown33 min
Jun 20, 11:12 PM CDTSevere Thunderstorm WarningTOPMarshall, Nemaha33 min
Jun 20, 11:37 PM CDTSevere Thunderstorm WarningTOPMarshall, Nemaha, Pottawatomie, Riley38 min
Jun 20, 11:54 PM CDTAreal Flood AdvisoryTOPBrown7 hr
Jun 21, 12:28 AM CDTAreal Flood AdvisoryTOPClay, Cloud, Geary, Ottawa, Pottawatomie, Riley15 min
Jun 21, 12:34 AM CDTSpecial Weather StatementTOPGeary, Pottawatomie, Riley41 min
Jun 21, 12:43 AM CDTFlash Flood WarningTOPClay, Cloud, Geary, Ottawa, Pottawatomie, Riley4 hr
Jun 21, 1:01 AM CDTSpecial Weather StatementTOPBrown44 min
Jun 21, 1:25 AM CDTSpecial Weather StatementTOPDickinson50 min
Jun 21, 1:40 AM CDTFlash Flood WarningTOPGeary, Riley4 hr
Jun 21, 1:44 AM CDTRiver Flood WarningTOPOttawa14 hr
Jun 21, 1:56 AM CDTSpecial Weather StatementTOPMorris34 min
Jun 21, 2:20 AM CDTRiver Flood WarningTOPRiley6 hr
Jun 21, 2:29 AM CDTSpecial Weather StatementTOPOsage31 min
Jun 21, 2:32 AM CDTAreal Flood AdvisoryTOPJackson, Nemaha3 hr
Jun 21, 2:53 AM CDTAreal Flood AdvisoryTOPGeary, Lyon, Morris, Wabaunsee3 hr
Jun 21, 3:04 AM CDTFlash Flood WarningTOPJackson, Jefferson, Osage, Pottawatomie, Shawnee, Wabaunsee4 hr
Jun 21, 3:40 AM CDTAreal Flood AdvisoryTOPDouglas, Franklin, Jefferson, Lyon, Osage, Shawnee and 1 more5 hr
Jun 21, 4:41 AM CDTAreal Flood AdvisoryTOPClay, Geary, Pottawatomie, Riley4 hr
Jun 21, 7:02 AM CDTRiver Flood WarningTOPShawnee4 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.