Alert archive / Kansas / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 21, NWS Hastings, NE

April 25, 20264 counties in Kansas

NWS Hastings, NE issued this severe thunderstorm warning at Apr 25, 2026, 4:42 PM CDT for 4 counties in Kansas. It was in force for 48 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
Apr 25, 2026, 4:42 PM CDT (21:42 UTC)
Expired
Apr 25, 2026, 5:30 PM CDT
In force
48 min
Issued by
NWS Hastings, NE
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Jewell County, KS, Mitchell County, KS, Osborne County, KS, Smith County, KS

The radar

The Grand Island radar (KUEX), 86 km from the middle of the area, began a volume at 21:44 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Apr 25, 2:43 PM CDTSevere Thunderstorm WatchSPC6 hr

The text

As transmitted.

480 
WUUS53 KGID 252142
SVRGID
KSC089-123-141-183-252230-
/O.NEW.KGID.SV.W.0021.260425T2142Z-260425T2230Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Hastings NE
442 PM CDT Sat Apr 25 2026

The National Weather Service in Hastings has issued a

* Severe Thunderstorm Warning for...
  Northwestern Mitchell County in north central Kansas...
  Southwestern Jewell County in north central Kansas...
  Southeastern Smith County in north central Kansas...
  Northeastern Osborne County in north central Kansas...

* Until 530 PM CDT.

* At 442 PM CDT, severe thunderstorms were located along a line
  extending from 6 miles southwest of Ionia to Cawker City, moving
  east at 15 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* Severe thunderstorms will be near...
  Cawker City around 445 PM CDT.
  Glen Elder around 450 PM CDT.
  Ionia around 500 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3947 9849 3954 9858 3961 9857 3965 9850
      3971 9818 3937 9817
TIME...MOT...LOC 2142Z 275DEG 15KT 3961 9845 3949 9843 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

ADP
2 follow-up statements
898 
WWUS53 KGID 252153
SVSGID

Severe Weather Statement
National Weather Service Hastings NE
453 PM CDT Sat Apr 25 2026

KSC141-183-252203-
/O.CAN.KGID.SV.W.0021.000000T0000Z-260425T2230Z/
Smith KS-Osborne KS-
453 PM CDT Sat Apr 25 2026

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN SMITH AND
NORTHEASTERN OSBORNE COUNTIES IS CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 900 PM CDT for
north central Kansas.

&&

LAT...LON 3946 9845 3957 9849 3965 9850 3971 9818
      3937 9817
TIME...MOT...LOC 2153Z 275DEG 15KT 3961 9839 3949 9837 

$$

KSC089-123-252230-
/O.CON.KGID.SV.W.0021.000000T0000Z-260425T2230Z/
Mitchell KS-Jewell KS-
453 PM CDT Sat Apr 25 2026

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 530 PM CDT
FOR NORTHWESTERN MITCHELL AND SOUTHWESTERN JEWELL COUNTIES...

At 453 PM CDT, severe thunderstorms were located along a line
extending from near Ionia to near Cawker City, moving east at 15 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

These severe storms will be near...
  Glen Elder around 500 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3946 9845 3957 9849 3965 9850 3971 9818
      3937 9817
TIME...MOT...LOC 2153Z 275DEG 15KT 3961 9839 3949 9837 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

ADP
917 
WWUS53 KGID 252224
SVSGID

Severe Weather Statement
National Weather Service Hastings NE
524 PM CDT Sat Apr 25 2026

KSC089-123-252233-
/O.EXP.KGID.SV.W.0021.000000T0000Z-260425T2230Z/
Mitchell KS-Jewell KS-
524 PM CDT Sat Apr 25 2026

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN MITCHELL AND
SOUTHWESTERN JEWELL COUNTIES WILL EXPIRE AT 530 PM CDT...

This Severe Thunderstorm Warning has been replaced with a Severe 
Thunderstorm Warning for northeastern Mitchell and southeastern 
Jewell Counties until 600 PM CDT.

A Severe Thunderstorm Watch remains in effect until 900 PM CDT for
north central Kansas.

&&

LAT...LON 3946 9845 3957 9849 3965 9850 3971 9818
      3937 9817
TIME...MOT...LOC 2223Z 275DEG 15KT 3960 9823 3948 9821 

$$

ADP

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 Hastings, NE wrote its last area forecast discussion before this severe thunderstorm warning went out at Apr 25, 12:41 PM CDT, 4 hours 1 minute earlier. Its key messages:

  • Severe storms may move across portions of the area this afternoon into early this evening. Large hail and damaging winds are the main threats.
  • There is a higher threat of severe storms for Sunday but more uncertainty in the timing of the storms. Large hail and damaging winds are the main threats.
  • Low temperatures Monday night and Tuesday night are expected to be in the upper 20s to 30s. This may lead to frost and freeze concerns.
Area forecast discussion, Apr 25, 12:41 PM CDT, 4 hours 1 minute before
Area Forecast Discussion
National Weather Service Hastings NE
1241 PM CDT Sat Apr 25 2026

.KEY MESSAGES...

- Severe storms may move across portions of the area this
  afternoon into early this evening. Large hail and damaging
  winds are the main threats.

- There is a higher threat of severe storms for Sunday but more
  uncertainty in the timing of the storms. Large hail and
  damaging winds are the main threats.

- Low temperatures Monday night and Tuesday night are expected
  to be in the upper 20s to 30s. This may lead to frost and
  freeze concerns.

&&

.UPDATE...
Issued at 142 AM CDT Sat Apr 25 2026

Showers have developed across northern and central portions of
Nebraska in association with an upper low centered over Canada that
extends southward to Nebraska. A cold front associated with this low
is also moving southward across western and northern portions of
Nebraska. Winds across the forecast area are beginning to turn to
the north generally along and north of I-80 and mostly out of the
southeast south of I-80. Overnight low temperatures are expected to
mostly be in the 40s with some upper 30s in far northwestern
portions of the forecast area. Showers and storms are expected to
develop and move southeastward along the cold front today. There
will likely be some thunderstorm development along the front this
morning with the main storm development expected during the
afternoon and early evening hours. Some of the storms that develop
later today may become severe with large hail and damaging winds
being the main threats due to fairly high instability and wind shear
along and ahead of the front. The front will not be very quick to
move through the area today which will allow for more time for the
atmosphere ahead of the front to become unstable. Although,
instability ahead of the front today may become impacted somewhat by
cloud cover. High temperatures today will be quite variable due to
the cold front with highs ranging from the 40s in the far northwest
to the 70s in the southeast and far east. The front will continue
moving through the area during the evening hours. Winds across the
area will be out of the north tonight with lingering showers
possible (around a 15% to 35% chance) for most of the overnight
hours. Low temperatures tonight will mostly be in the 30s and 40s.

Chances of showers and storms will increase (up to around 90%-95%)
from the west late tonight into Sunday morning. There is quite a bit
of uncertainty with regards to how rain and storms will develop on
Sunday. Some models show western and northern portions of the
forecast area having the highest chances of precipitation during the
day on Sunday with most of the rain and storms moving through on
Sunday night. A high-res model shows a round of showers and storms
moving across the majority of the forecast area during the day on
Sunday. There will be fairly high instability, wind shear, and lift
that whenever storms do develop and move across the area, they will
have the potential to become severe. Southern portions of the area
are in an enhanced risk (level 3 out of 5) according to the Storm
Prediction Center's Day 1 severe outlook. The rest of the area is in
a marginal to slight risk (level 1 and 2). Large hail and damaging
winds will be the main threats with these storms although there is a
low threat of an isolated tornado. The highest threat of severe
storms will be in north central Kansas. High temperatures on Sunday
are generally expected to be in the 50s and 60s. Looking ahead, low
temperatures Monday night and Tuesday night are expected to be
mostly in the 30s with some upper 20s across the far northwest
(northwest of the Tri-Cities area). This will create possible freeze
and frost concerns.

&&

.DISCUSSION...
Issued at 445 PM CDT Fri Apr 24 2026

Vast majority of this discussion will be focused on the next few
days since that's where the most impactful weather looks to be.

A surface ridge axis is currently overhead and leading to very
nice conditions (bonus points for being a Friday!) featuring
relatively light winds and temperatures in the 60s-lower 70s.
The ridge axis will continue to shift E/SE, which will allow for
increasing SErly return flow. This increase in winds is already
noted in observations just to our W and there remains a small
window for near critical fire weather conditions for areas W of
Hwy 183 where the increasing winds overlap with slowly rising,
but still sub-30%, RHs between around 5-9PM. Most of the night
should remain dry, though held onto some low PoPs in the far
W/NW near an approaching cold front.

This front will make gradual NW to SE progression on Saturday,
but then likely stall out at some point during the afternoon as
a sfc low deepens along NW KS/SW NE border area. Exactly where
this stall occurs remains a bit uncertain...and it will have a
huge affect on the sensible weather for a given location. Areas
from around Lexington to Ord may remain stuck in clouds and
chilly N wind all day and temperatures only in the 40s to 50s...
whereas Osborne to Geneva area could warm well into the 70s
amidst broken cloud cover and warm/moist Srly flow. The heart
of the forecast area, including the Tri-Cities, could have
sensible weather that's just about anywhere in between. Agree
with recent hi-res data that shows iso-scat shwrs/weak storms
developing along the front Sat AM, with a gradual uptick in
intensity towards midday. Question will be just how much of an
increase we see, especially across Neb zones, given somewhat
lackluster heating and instability. While not a textbook case by
any means, wouldn't rule out some funnels/weak tornadoes in
south central NE given proximity to potential differential
heating and decent 0-3km CAPE that overlaps strong ambient low
level vorticity associated with the slow-moving front. Sometimes
this can support rapid low level stretching and weak tornadoes.

More likely scenario for robust convection will be new
development on the southern flank of existing convection into
north central Kansas in vicinity of a sfc low and associated
triple point during the mid to late afternoon. These areas could
support greater instability and MLCAPE of at least 1000 J/kg by
late afternoon. Deep layer shear would be strong enough, and
favorably oriented relative to dry line, to support supercells
with large hail. Have increased hail size potential in messaging
up to around golf ball size given potential storm mode, steep
mid level lapse rates, and large chunk of the CAPE being within
favored hail growth zone. Model UH tracks support a hard right
turn and a potential increase to already favorable low level
hodographs for tornadoes with any late aftn-early eve
supercells. Appears the main limiting factor to a more robust
tornado threat could be marginal BL moisture as TDs remain in
the 50s. Overall coverage of convection into north central and
central KS may be less than further north, but this would allow
what does develop to be more intense. Storms should clear the
area to the SE by around midnight.

Attention then turns to even better and more widespread shower
and storm chances on Sunday. Will start off by saying there is
considerable uncertainty in how things will play out. Model
differences are high and appears that increasing elevated
convection Sunday AM could throw a significant wrench into
afternoon destabilization potential. Also, the primary upper
trough/height falls appears a bit late for optimal overlap with
peak daytime heating - suggesting maybe the traditional late
afternoon and early evening window for severe weather could be
fairly quiet locally and focused further S/SE into axis of
greater instability. Really it will just depend on how
widespread AM elevated convection is and where any potential
outflow/differential heating boundaries set up. My personal
experience is that more often than not, early day convection is
more detrimental to severe aftn/eve storms than what models
suggest...especially in late April north of a warm front. Warm
air advection will be pretty strong Sat night-Sun AM with a
veering low level jet beneath a coupled upper jet. This should
be a pretty good opportunity for some widespread, much-needed
rainfall with perhaps a marginal severe hail threat, as well. If
this activity doesn't clear the area until mid to late afternoon
(as the 18Z HRRR shows), then the window to recover would just
be too small (in time and space) to recover. In this scenario,
the "main show" would be along and S of I-70.

Under this scenario, some of our highest severe chances might
actually be during the overnight Sun night with the arrival of
the main upper trough and northward surge of warm/moist airmass
on a strong low level jet. Obviously, a late night trough
passage isn't optimal for robust surface based severe storms,
but some elevated supercells with large hail could certainly be
in the realm of possibilities. This could perhaps coincide with
arrival of convection from the W that developed along the Front
Range and grew upscale into the strengthening low level jet.
Again...just a lot of uncertainty and potential scenarios and
even with the large coverage of the Enhanced Risk, don't want
people to think Sunday is a forgone conclusion of a classic
significant severe weather outbreak *for our area*. It still
could be, but I think the pattern/timing lends itself to one
where the greatest strong tornado threat lies along/S of I-70.

Regardless of exact details...think we're looking at three solid
chances for rain between Saturday afternoon and Monday AM. Feel
fairly comfortable in saying that most people should expect at
least a half inch over the weekend, and let's hope that at least
one of the elevated convection potentials (Sat night or Sun
night) pans out such that swaths of 1-1.5"+ also occur.

Rest of the forecast is seasonably cool with off and on rain
chances.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1239 PM CDT Sat Apr 25 2026

For KGRI/KEAR Airports:

Significant weather: Scattered thundershowers this afternoon,
then widespread IFR to perhaps LIFR conditions this evening
through Sunday morning.

Scattered showers and thunderstorms will gradually work W to E
across the terminals over the next several hours. Most of the
heavier cores are just E of EAR, and can't rule out some small
hail for GRI through ~21-22Z. Organized showers should shift E
by this evening, but it will remain damp/dreary under IFR CIGs
and at least MVFR VSBYs all night. Will likely deteriorate to
LIFR CIGs after midnight, and VSBYs could fall to IFR, but this
is more uncertain. The next chance for showers and embedded
t-storms looks to arrive from the W late Sun AM.

Winds will mainly be NE to N through the period, averaging
10-15kt sustained, with some occasional gusts around 20kt.
Confidence: Wind & CIGs - High, Timing of rain & VSBY - Med.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...None.
KS...None.

&&

UPDATE...Schuldt
DISCUSSION...Thies
AVIATION...Thies
Hazardous weather outlook, Apr 25, 3:17 PM CDT, 1 hour 25 minutes before
Hazardous Weather Outlook
National Weather Service Hastings NE
317 PM CDT Sat Apr 25 2026

KSZ005>007-017>019-NEZ039>041-046>049-060>064-072>077-082>087-
261200-
Phillips-Smith-Jewell-Rooks-Osborne-Mitchell-Valley-Greeley-Nance-
Sherman-Howard-Merrick-Polk-Dawson-Buffalo-Hall-Hamilton-York-
Gosper-Phelps-Kearney-Adams-Clay-Fillmore-Furnas-Harlan-Franklin-
Webster-Nuckolls-Thayer-
317 PM CDT Sat Apr 25 2026

This Hazardous Weather Outlook is for south central Nebraska and
portions of north central Kansas.

.DAY ONE...This Afternoon and Tonight.

Severe thunderstorms are possible this afternoon and evening,
mainly for areas south and east of Hastings where a Severe
Thunderstorm Watch is in effect. Large hail up to around half
dollar size and wind gusts up to around 60 MPH are the main
threats.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

There is a marginal to enhanced risk of severe storms Sunday.
There is still considerable uncertainty with regards to exact
timing, location, and magnitude of severe threat, which is further
complicated by the possibility there could be more than one round
of thunderstorms. At this time, it appears there could be at least
a few strong to severe storms with a round of storms in the
afternoon, with perhaps another, possibly more intense, round
during the late evening and overnight. Both rounds favor areas
along and south of the state line for the greatest severe threat
in both coverage and magnitude. Very large hail to golf ball size,
or larger, damaging wind gusts of 60 to 70 MPH, and a few
tornadoes will be possible.

Non-severe thunderstorms could linger into Monday morning.

Frost and freeze concerns may return to much of the area each
night/morning next week as low temperatures drop into at least
the low to mid 30s.

.SPOTTER INFORMATION STATEMENT...
Spotters are encouraged to report any hail and/or damaging wind
gusts.

&&

More information may be obtained at the following web page:
   https://www.weather.gov/hastings

Thies

In the hours before

Special weather statement, Apr 25, 3:58 PM CDT, 44 minutes before
Special Weather Statement
National Weather Service Hastings NE
358 PM CDT Sat Apr 25 2026

NEZ063-064-252145-
Hamilton NE-York NE-
358 PM CDT Sat Apr 25 2026

...A STRONG THUNDERSTORM WILL IMPACT WESTERN YORK AND HAMILTON
COUNTIES THROUGH 445 PM CDT...

At 358 PM CDT, Doppler radar was tracking a strong thunderstorm near
Giltner, or 18 miles southeast of Grand Island, moving east at 25
mph.

HAZARD...Wind gusts up to 50 mph and penny size hail.

SOURCE...Radar indicated.

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

This strong thunderstorm will be near...
  Aurora around 410 PM CDT.

Other locations in the path of this storm include Hampton, Henderson
and Bradshaw.

This includes Interstate 80 between mile markers 320 and 351.

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.

&&

LAT...LON 4070 9805 4070 9825 4082 9824 4105 9780
      4076 9758
TIME...MOT...LOC 2058Z 249DEG 23KT 4077 9808

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...50 MPH

Mangels
Local storm report, Apr 25, 4:10 PM CDT, 32 minutes before
Preliminary Local Storm Report
National Weather Service Hastings NE
410 PM CDT Sat Apr 25 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0345 PM     Tstm Wnd Gst     3 SW Henderson          40.75N 97.85W
04/25/2026  M55 MPH          Hamilton           NE   Mesonet

            Wunderground station KNEHENDE4.

&&

Mangels
Local storm report, Apr 25, 4:16 PM CDT, 26 minutes before
Preliminary Local Storm Report
National Weather Service Hastings NE
416 PM CDT Sat Apr 25 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0346 PM     Tstm Wnd Gst     1 WNW Henderson         40.79N 97.84W
04/25/2026  M54 MPH          Hamilton           NE   Mesonet

            KNEHENDE5.

&&

Mangels
Local storm report, Apr 25, 4:20 PM CDT, 22 minutes before
Preliminary Local Storm Report
National Weather Service Hastings NE
420 PM CDT Sat Apr 25 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0338 PM     Hail             5 NE Harlan             39.65N 98.70W
04/25/2026  E1.00 Inch       Smith              KS   Trained Spotter

            Hail covering the ground. Reported nickel
            size or slightly larger. Time estimated from
            radar.

&&

Mangels
Special weather statement, Apr 25, 4:25 PM CDT, 17 minutes before
Special Weather Statement
National Weather Service Hastings NE
425 PM CDT Sat Apr 25 2026

NEZ049-064-252215-
York NE-Polk NE-
425 PM CDT Sat Apr 25 2026

...A STRONG THUNDERSTORM WILL IMPACT YORK AND SOUTHERN POLK COUNTIES
THROUGH 515 PM CDT...

At 425 PM CDT, Doppler radar was tracking a strong thunderstorm near
York, moving northeast at 35 mph.

HAZARD...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. Minor hail damage to vegetation is
         possible.

This strong thunderstorm will be near...
  York around 430 PM CDT.

Other locations in the path of this storm include Gresham.

This includes Interstate 80 between mile markers 348 and 365.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4076 9766 4101 9783 4109 9783 4119 9737
      4077 9737
TIME...MOT...LOC 2125Z 243DEG 29KT 4089 9767

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

Mangels
Local storm report, Apr 25, 4:37 PM CDT, 5 minutes before
Preliminary Local Storm Report
National Weather Service Hastings NE
437 PM CDT Sat Apr 25 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0431 PM     Non-Tstm Wnd Gst York Airport            40.89N 97.62W
04/25/2026  M68 MPH          York               NE   AWOS

            Report from York Airport. Exact time
            estimated from radar.

&&

Mangels

The office that day

Everything else NWS Hastings, NE issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 25, 3:07 PM CDTSevere Thunderstorm WarningGIDSmith23 min
Apr 25, 3:25 PM CDTSevere Thunderstorm WarningGIDOsborne, Smith35 min
Apr 25, 3:54 PM CDTSevere Thunderstorm WarningGIDJewell, Mitchell, Osborne, Smith51 min
Apr 25, 5:17 PM CDTSevere Thunderstorm WarningGIDJewell, Mitchell43 min
Apr 25, 5:59 PM CDTSpecial Weather StatementGIDMitchell31 min
Apr 25, 6:14 PM CDTSevere Thunderstorm WarningGIDMitchell31 min

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; radar from the NEXRAD Level II archive.