EF0 tornado, Newark to Gibbon, Nebraska, December 15, 2021

1. EF065 to 85 mphthis tornado

   Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

2. EF186 to 110 mph

   Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

3. EF2111 to 135 mph

   Considerable damage. Roofs torn off well-built houses, frame homes shifted on their foundations, mobile homes destroyed, large trees snapped or uprooted, cars lifted off the ground.

4. EF3136 to 165 mph

   Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

5. EF4166 to 200 mph

   Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

6. EF5over 200 mph

   Incredible damage. Strong frame houses swept off their foundations, car-sized missiles thrown more than 100 meters, steel-reinforced concrete badly damaged, high-rise buildings deformed.

7. Unrated

   The survey recorded a tornado but could not put a number on it, most often because it crossed open country and damaged nothing a rating can be read from.

Rating

EF0

Date

December 15, 2021

Touchdown

1:27 PM CST (19:27 UTC)

Lifted

1:38 PM CST (19:38 UTC)

On the ground

11 minutes

Path length

11.0 miles (17.7 km)

Path width

150 yards (137 m)

Deaths

0

Injuries

0

Property damage

$700,000

Counties

Kearney and Buffalo counties

Touchdown point

40.583, -98.939

Lift-off point

40.730, -98.860

Record number

2112151327-01

18 damage points were recorded along this path by NWS GID, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 85 mph.

• Pivot 1/4 mile east-several towers
• Pivot 1/4 mile southeast. Hays bales rolled to northeast on path.
• Entire pivot turned over. Right on path.
• Pivot 1/4 mile north. Appears to a bit of fresh tree damage in tree line. Minor in nature.

Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.

A historic onslaught of swift moving severe thunderstorms with embedded tornadoes, followed by several hours of severe gradient winds and areas of blowing dust/smoke (and even a touch of wind-whipped snow) unfolded within South Central Nebraska on this Wednesday afternoon-evening, with the local area serving as the initiation zone of what would not only end up being the most impactful convective event on record during the month of December for the state of Nebraska (far eclipsing Christmas Day 2016), but also for other nearby states including IA/MN. In fact, the nearly continuous swath of damaging winds that stretched from south central NE/north central KS northeastward into southeast MN/western WI was officially declared a serial derecho...the first December derecho on record in the United States. Including nine confirmed tornadoes in South Central Nebraska (and 19 others that occurred in eastern NE), there were 28 confirmed tornadoes within the state...a remarkable fact considering that prior to this day only five Nebraska tornadoes had occurred in December since 1950! Focusing exclusively on the local South Central NE area going forward, the nine tornadoes consisted of five rated EF-1 and four rated EF-0. There were also dozens of measured reports of damaging winds in the 60-80+ MPH range (both thunderstorm/non-thunderstorm), including a peak thunderstorm gust of 85 MPH at Central Nebraska Regional Airport in Grand Island and a peak non-thunderstorm gust of 77 MPH by an unofficial mesonet in southwestern Clay County. Fortunately, there were no reported injuries, despite countless instances of damage primarily to irrigation pivots, outbuildings, power lines/poles and trees. ||Breaking down event evolution/timing for the local area, first of all, even before convection flared up it was already an unusual/noteworthy December weather day given unseasonable warmth/humidity being pumped into the area on strong south winds. By late morning-early afternoon, southerly gusts were commonly 35-50 MPH as temperatures soared into the mid-60s to low-70s F (setting new Dec. 15th records in Grand Island/Hastings), accompanied by dewpoints surging at least briefly into the 50s F (mainly near/east of Highway 281). This set the stage for severe convection/tornadoes during the early-mid afternoon, as the squall line that eventually impacted all but a few far western local counties raced through South Central NE at an incredible average forward motion of 65-75 MPH. The squall line, which was still in its infant stages as it entered Harlan County out of Kansas shortly before 1 p.m., rapidly intensified/expanded in scope while reaching the Highway 281 corridor by 2 p.m., and then in the blink of an eye had all-but-exited the extreme eastern fringes of the local area (Highway 81 counties) by 3 p.m....wrapping up a brief-but-wild two hours of weather. As for the nine confirmed South Central NE tornadoes, they all occurred between 1:27-2:43 p.m. and had at-times-intermittent path lengths between 7-15 miles. The tornadoes concentrated within counties mainly situated between the Highway 92 and Highway 6 corridors, touching down as far west as eastern Kearney/Franklin counties and as far east-northeast as Hamilton/Polk counties. The circulations were firmly embedded within the aforementioned squall line, making these quasi linear convective system (QLCS) tornadoes with often-intermittent damage paths. As is typical of such tornadoes, there was little in the way of clear cut photographic/video evidence, with the main exception consisting of a more classic looking photo of an EF-1 near Marquette. Although specific details regarding each of the nine tornadoes can be found in their respective event narratives, the vast majority of damage occurred to irrigation pivots, power poles/lines and a handful of outbuildings/grain bins, including a few fairly large metal outbuildings that were partially or completely demolished within only a few miles of communities such as Hastings, Marquette and Polk. Fortunately, no homes suffered major damage, although a few sustained relatively minor roof/siding issues. And although there were no reported injuries, one family north of Hastings had a fairly close call as their sport utility vehicle had several windows blown out of it only about one minute after they arrived home and sought shelter. Although straight-line thunderstorm winds along the surging line took a publicity backseat to the tornadoes, there were dozens of reported measured/estimated gusts of at least 60-70 MPH, and a handful of measured gusts as high as 75-85 MPH, highlighted by 85 MPH at Central Nebraska Regional Airport (official) and unofficial mesonet gusts of 84 MPH near Shickley, 83 MPH near Davenport and 81 MPH near Oxford. As just a sampling of damage attributed to convective winds: a blown-over semi truck on Highway 6 near Hastings; an overturned pickup truck and trailer along I-80 near Grand Island; significant roof and siding damage to a brick building in downtown Giltner; a metal outbuilding largely destroyed near Fullerton; a carport lofted into power lines in Bruning. Lastly in the convective department, hail was a minimal issue for the vast majority of South Central Nebraska. However, stones up to golf ball size significantly damaged a home near Marquette, while slightly smaller, wind-driven hail up to quarter size was reported in the Grand Island and Hastings areas, including a report of considerable damage to siding, fences and shingles in the Lake Hastings area.||Turning to non-convective severe winds, for the majority of South Central Nebraska they peaked in intensity a few hours after the passage of the squall line (and also impacted those few far western counties that were spared by convection), ramping up initially from the southwest and eventually west-northwest behind a surging composite cold front/dryline. Generally speaking, roughly the southwestern half of the local area observed its strongest non-convective winds between 2-7 p.m., while the northeastern half of the area peaked more so 4-9 p.m. However, the entire area endured at least a few hours of sustained speeds commonly 30-45 MPH and sporadic gusts of 50-70 MPH, including official peak gusts of 73 MPH at Hastings and Ord airports, and unofficial peak mesonet gusts of 77 MPH near Glenvil, 76 MPH near Davenport and 75 MPH near Norman. Although these non-convective winds undoubtedly caused considerable minor damage and/or exacerbated damage already done by earlier convective winds, specific reports were actually quite limited. However, one unique highlight of these southwesterly-turning-westerly winds is that they shrouded much of the local area a under an eerie pall for a few hours during the mid-late afternoon...a combination of blowing dust (emanating off the western High Plains) and also smoke (from large wildfires in northern KS) that reduced visibility to under a mile in some spots. Fortunately, no wildfires were sparked within South Central NE itself, despite favorable conditions for large fire growth behind the dryline (especially in southwestern counties). The final severe-criteria gust of the evening (59 MPH) occurred in Nance County shortly after 7 p.m., and gusts eased down to only 30-40 MPH within most of South Central NE by 10 p.m.||The last weather element of this multi-faceted event (and ironically of least-overall impact for December) was snow, as far western/northwest portions of the local area observed roughly a one-hour period of wind-whipped snow between 3:30-5:30 p.m. as a weakening deformation zone on the backside of the system clipped parts of mainly Dawson, Sherman, Valley and far western Buffalo counties. Although total accumulations were mainly at-or-below one-half inch and there were no reports of significant travel impacts, the fact that this snow band prompted brief, greatly-reduced visibility reductions along Interstate 80 prompted the first-ever Snow Squall Warning issuance within South Central NE.||Examining the meteorology behind this event, this would have been considered a powerhouse setup for severe convection/high winds during the more typical spring season usually associated with this type of system, let alone in mid-December. In the mid-upper levels, not only was the parent, negatively-tilted shortwave trough notably intense as it slammed across the central United States, but it was also notably fast. At daybreak, its vorticity maximum was just passing by the Four Corners, but by mid-day it had already reached the NE/CO/KS border area and by sunset had advanced into far northeast NE. At the 500-millibar level, a stout jet streak of 100+ knots nosed into South Central NE from the south-southwest during the afternoon, while lower in the column a potent southerly low level jet (evident at 850 millibars) ramped up to 40-60 knots. At the surface, a vigorous low pressure center sliced across the heart of Nebraska from southwest-to-northeast during the afternoon, deepening to around 984 millibars along the way and driving a sharp dryline/cold frontal combo eastward through the area. As mentioned, surface dewpoints climbed into the 50s F across much of the area prior to convective initiation, fostering a corridor of mixed-layer CAPE up to 500-1000 J/kg. Although somewhat modest instability values by warmer-season standards, in this case it was more than enough to promote robust severe convection in the presence of extreme wind fields, with embedded QLCS tornadoes no surprise given 0-1 kilometer bulk shear around 40 knots and effective storm-relative helicity (SRH) around 200-300 m2/s2. In the wake of the squall line, the ensuing non-convective wind event corresponded to a zone of deep subsidence (likely associated with a sting jet) and a pronounced surface pressure gradient on the backside of the departing low, with a 16-millibar gradient noted across South Central NE at 6 p.m. (ranging from 988 mb at Columbus to 1004 mb at McCook).||Closing with some comments about official NWS forecasts leading up to this historic event, there was excellent awareness several days in advance regarding the likelihood of powerful non-convective winds both ahead of (southerlies) and behind (westerlies) the intense surface low pressure system. An area-wide High Wind Watch was issued early on the 13th (48-60 hours in advance) and was subsequently upgraded to a High Wind Warning early on the 14th. However, what was not as well anticipated (both at the local and national forecast level) was how great of a convective/tornado threat South Central NE would face, as the fast-tracking squall line ended up forming slightly earlier and several counties farther west than most model data suggested (especially 12+ hours out). As a result, there was a noticeable ramp-up of convective threat categories within South Central NE on Dec. 15th SPC Day 1 Outlooks, progressing from the initial 06Z outlook that barely brushed the far eastern fringes of the area with a Marginal Risk (level 1 of 5), to the 1630Z outlook that correctly shifted Slight (level 2) and Enhanced (level 3) categories westward into several counties along/east of Highway 281.

This tornado started in Kearney County north of Minden and crossed into Buffalo County, lifting near Gibbon. This tornado was typical for the day, likely intermittent with regard to ground circulation and impacting rural areas. Much of the path damage can be traced to center irrigation pivots either partially or fully overturned. The tornado damaged a couple power poles and peeled back some roofing material at the Rowe Sanctuary. A measured wind gust 83 MPH was recorded at the sanctuary as the storm passed. Damage was a bit sparse north of the river. The tornadic circulation likely crossed Interstate 80 about three miles west of the Gibbon interchange before knocking over a couple more pivots and lifting just southwest of Gibbon. The maximum estimated speed of 85 MPH was based upon the measured wind gust at the sanctuary and damage to nearby power poles.

This tornado is a continuation of the tornado that touched down in Kearney County, north of Minden. This tornado was typical for the day, likely intermittent with regard to ground circulation and impacting rural areas. Much of the path damage can be traced to center irrigation pivots either partially or fully overturned. The tornado damaged a couple power poles and peeled back some roofing material at the Rowe Sanctuary. A measured wind gust 83 MPH was recorded at the sanctuary as the storm passed. Damage was a bit sparse north of the river. The tornadic circulation likely crossed Interstate 80 about three miles west of the Gibbon interchange before knocking over a couple more pivots and lifting just southwest of Gibbon. The maximum estimated speed of 85 MPH was based upon the measured wind gust at the sanctuary and damage to nearby power poles.

This shorter path tornado started east of Lowell in Kearney County and traveled north-northeast across the Platte River into Buffalo County. Damage was sparse, but a few center irrigation pivots and minor tree damage was found. The tornadic circulation likely crossed Interstate 80 about 2.5 miles west of the Shelton interchange. The tornado moved across one farmstead where a garage was completely destroyed. Minor tree damage was also noted. The damage to the garage was the primary basis for the 80 MPH maximum wind speed estimate. The tornado tipped one more pivot before lifting just northeast of the farmstead.

This tornado is a continuation of the tornado that touched down east of Lowell in Kearney County and traveled north-northeast across the Platte River into Buffalo County, lifting near Shelton. Damage was sparse, but a few center irrigation pivots and minor tree damage was found. The tornadic circulation likely crossed Interstate 80 about 2.5 miles west of the Shelton interchange. The tornado moved across one farmstead where a garage was completely destroyed. Minor tree damage was also noted. The damage to the garage was the primary basis for the 80 MPH maximum wind speed estimate. The tornado tipped one more pivot before lifting just northeast of the farmstead.

From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down.

Every warning and watch covering the touchdown point that day, from the Iowa Environmental Mesonet's archive of National Weather Service products. Lead time is measured from the issue of the warning in force to the touchdown time in the database, both of which were recorded to the minute by different people.

The Storm Prediction Center had this point in a General Thunderstorms Risk. The outlook in force was issued at 16:25 UTC.

SPC's Day 1 convective outlook as it stood when the tornado began, read at the touchdown point. The same archive is on the radar archive.

NWS Hastings, NE wrote its last area forecast discussion before the tornado touched down at Dec 15, 12:15 PM CST, 1 hour 12 minutes earlier.

AREA FORECAST DISCUSSION
National Weather Service Hastings NE
1215 PM CST Wed Dec 15 2021

.DISCUSSION...(Today through Tuesday)
Issued at 312 AM CST Wed Dec 15 2021

Here we go. The main event and focus of the forecast is today
with winds expected to rapidly increase later this morning to
potentially historic levels. Currently, southerly winds are
already beginning to increase early this morning as a very strong
low pressure system crosses the Rockies and deepens. By midday
today, sustained southerly winds of 40 to 50 mph with gusts to 70
mph or greater will be experienced across Nebraska and Kansas.
This will continue through the afternoon and into the evening,
with winds switching to southwesterly and westerly this afternoon
and northwesterly later this evening as the front passes through.
As such, a High Wind Warning is in effect from 9AM to 9PM today.
With most of north central Kansas still dry and avoiding much
moisture from previous systems, elected to add the possibility of
blowing dust to the forecast for that area, especially as the
strongest wind gusts are expected to occur there. It is best to
stay inside during this event but if you MUST be outdoors, use
extreme caution as these winds can easily blow down trees and
power poles. Widespread power outages are also very possible.

In addition, with the southerly winds today, there will be enough
moisture to see isolated thunderstorms today, mainly along and
east of Highway 14. With a few hundred joules of CAPE, cannot rule
out a strong storm as the instability will be combined with decent
shear and a strengthening low. Any possible threat here should be
limited as the instability will move to the east of the area
during the afternoon.

Warmer temperatures will also come out of these strong southerly
winds. Ahead of the front, expect record or near record high
temperatures today. There will be very strong warm air advection,
which supports the idea of record temperatures but also brings
very low dewpoints and generally dangerous fire weather conditions.
With this, we are very confident in the Red Flag Warning that is
in effect through the evening.

Behind the cold front this evening as winds diminish some and
switch to the northwest, there is a chance for some light snow
across portions of south central Nebraska tonight. This should be
short-lived and no accumulation is expected.

Thursday onward, temperatures return to near normal for the next
several days. The next system anywhere near our area will be
associated with a low expected to pass just to our north Friday
night. However, this will push off to the northeast, keeping
precipitation well to our north, leaving our area with potentially
breezy conditions Friday evening into Saturday morning. Otherwise,
weather is expected to be much quieter for the remainder of the
forecast period starting Thursday.

&&

.AVIATION...(For the 18Z KGRI/KEAR TAFS through 18Z Thursday)
Issued at 1206 PM CST Wed Dec 15 2021

Biggest issue by far will be wind speeds. Exceptionally strong
wind speeds are expected with a dynamic system moving through.
High confidence with strong wind gusts as historically strong wind
gusts are forecast by hi-resolution models. Dust could be an issue
with visibility today, and we may need to lower to at least MVFR.
Also KEAR could be on the far south end of some falling snow,
driven by very strong wind which could also lower visibility near
and shortly after 00Z. LLWS is possible at the beginning of the
forecast before surface winds start to really ramp up. Slow
decrease to wind gusts into the overnight.

&&

.FIRE WEATHER...
Issued at 312 AM CST Wed Dec 15 2021

The combination of strong winds and low relative humidity
values will result in dangerous fire weather conditions across
the local area today. In addition to the strong winds, a change
in wind direction from the south southwest to the northwest with
the associated cold front this afternoon and evening will make any
fire that develops difficult. Avoid engaging in activities that
could lead to fire ignition today.

&&

.CLIMATE...
Issued at 359 PM CST Mon Dec 13 2021

..Regarding Potential Record High Temperatures Wed. Dec. 15 at
Grand Island/Hastings (our two primary climate records sites)..

WEDNESDAY (Dec. 15):
Although still subject to at least minor change, we are CURRENTLY
forecasting record or near record high temps for today...

                   Record Current       Forecast
Grand Island         67 in 2002          67 (tie)
Hastings             67 in 2002          67 (tie)

PLEASE NOTE: Although morning lows Wednesday may also "appear" to
threaten Dec. 15 records for warmest minimum temperature, keep in
mind that daily records are based off the FULL calendar day, and
at this time we expect temperatures to fall far enough this
evening (prior to midnight) to keep existing warm minimum temp
records intact (current records 35 at GRI/39 at HSI).

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...High Wind Warning until 9 PM CST this evening for NEZ039>041-
     046>049-060>064-072>077-082>087.

     Red Flag Warning until 9 PM CST this evening for NEZ048-049-
     062>064-075>077-084>087.

KS...High Wind Warning until 9 PM CST this evening for KSZ005>007-
     017>019.

     Red Flag Warning until 9 PM CST this evening for KSZ005>007-
     017>019.

&&

DISCUSSION...Hickford
AVIATION...Heinlein
FIRE WEATHER...Hickford
CLIMATE...Hickford

Hazardous Weather Outlook
National Weather Service Hastings NE
1130 AM CST Wed Dec 15 2021

KSZ005>007-017>019-NEZ039>041-046>049-060>064-072>077-082>087-
161200-
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-
1130 AM CST Wed Dec 15 2021

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

.DAY ONE...This Afternoon and Tonight.

An unusually high risk for hazardous weather is expected today
and this evening from multiple concurrent hazards.

Exceptionally strong winds are expected today, especially during
the afternoon through evening hours. These winds will start the
day out of the south, before turning to the west, then northwest
behind a passing cold front. Widespread wind gusts of 70 mph or
more are possible. A High Wind Warning is in effect for the
entire area morning through 9 PM this evening. Please refer to
the latest High Wind Warning message for additional information.

These strong winds, combined with low relative humidity, are also
expected to result in critical fire weather conditions for
portions of the area this afternoon. As a result...a Red Flag
Warning will be in effect for areas southeast of a line from
Columbus Nebraska to Grand Island to Phillipsburg Kansas from
Noon through 9 PM today. Please refer to the latest Red Flag
warning message for additional information.

There is potential for severe thunderstorms this early to mid
afternoon especially for areas along and east of Highway 281. A
marginal to slight severe risk of storms is possible for this
area much of this area and an enhanced risk for the Highway 81
corridor, mainly between the noon and 4 PM. Thunderstorm wind
gusts of 70-80 mph are the main potential threat, but an isolated
tornado cannot be ruled out.

With such exceptionally strong winds expected, visibility could
be reduced at times today due to blowing dust, and in some areas,
from falling snow.

Blowing dust will be possible for the entire outlook area,
especially for areas of north central Kansas all day today and
into this evening, and could reduce visibility to near zero for
some areas at times.

Falling snow combined with strong northwest wind gusts could
reduce visibility to less than a quarter mile for areas mainly
northwest of a line from Elwood to Kearney to Fullerton, Nebraska
late this afternoon and into the evening mainly between 5 PM and
9 PM.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Any reports of any wind damage from this event are appreciated.

&&

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

Heinlein

In the hours before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HASTINGS NE
116 PM CST WED DEC 15 2021

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

0100 PM     TSTM WND GST     7 ESE OXFORD            40.23N 99.50W
12/15/2021  M77 MPH          HARLAN             NE   MESONET

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HASTINGS NE
118 PM CST WED DEC 15 2021

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

0115 PM     TSTM WND GST     HOLDREGE AIRPORT        40.45N 99.34W
12/15/2021  M66 MPH          PHELPS             NE   AWOS

&&

PFANNKUCH

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HASTINGS NE
119 PM CST WED DEC 15 2021

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

0115 PM     TSTM WND GST     1 E WILCOX              40.36N 99.15W
12/15/2021  M72 MPH          KEARNEY            NE   MESONET

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HASTINGS NE
120 PM CST WED DEC 15 2021

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

0115 PM     TSTM WND GST     HUNTLEY                 40.21N 99.29W
12/15/2021  M60 MPH          HARLAN             NE   MESONET

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HASTINGS NE
124 PM CST WED DEC 15 2021

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

0124 PM     NON-TSTM WND GST 3 N GLEN ELDER          39.54N 98.31W
12/15/2021  M60 MPH          MITCHELL           KS   MESONET

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HASTINGS NE
127 PM CST WED DEC 15 2021

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

0111 PM     TSTM WND GST     4 E RAGAN               40.30N 99.21W
12/15/2021  M76 MPH          HARLAN             NE   MESONET

&&

The radiosonde launches on either side of the tornado, from the nearest station that was launching then, drawn and analyzed the way Storm Lab does: the same diagram, the same parcel and shear definitions SPC's mesoanalysis uses.

Kearney Municipal (EAR), 12 km from the path, in the two hours either side.

From the Iowa Environmental Mesonet's archive of airport observations.

The Grand Island radar (KUEX), 54 km away, was scanning. The volume nearest the touchdown began at 19:26 UTC.

Open the radar archive at this moment, over the track

Reflectivity and velocity, decoded from the Level II archive in the browser. Volumes take a few seconds to open the first time.

Local storm reports within 60 km of the path, in the three hours either side.

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

The live radar over the trackEvery 2021 tornado in NebraskaEvery tornado in Nebraska since 1950Warnings in force in Nebraska nowThe forecast where you are

124 more were confirmed in the United States that day.

All 125 of them

Ratings are the survey's, read off the damage rather than measured; the rating scale is above. Tornado counts rise through the record as reporting improved, so a year in the 1950s is not comparable with one today except for the strongest tornadoes, which were always noticed.

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.