An very anomalous storm system produced a squall line with embedded supercells on 12/15. The squall line impacted our entire CWA and caused widespread wind damage.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS TOP wrote it up.
An very anomalous storm system produced a squall line with embedded supercells on 12/15. The squall line impacted our entire CWA and caused widespread wind damage. Winds were reported as high as 100 mph with the line of storms, which is now referred to as a serial derecho. No tornadoes were confirmed.
The local office's own words before the first event, 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 the first event at Dec 15, 11:45 AM CST, 2 hours 43 minutes earlier.
Area Forecast Discussion
National Weather Service Topeka KS
1145 AM CST Wed Dec 15 2021
...Update to aviation forecast discussion...
.DISCUSSION...
Issued at 330 AM CST Wed Dec 15 2021
Key Points:
-Extremely Dangerous Fire Weather Conditions Today
-Very Strong Winds Today
-Isolated Severe Thunderstorms Possible Today
-Record High Temperatures Today
A historic storm system will impact the area today.
For fire weather information see the fire weather discussion
below.
Winds...
An anomalous surface/upper-level low pressure system will eject
into the central Plains today. Model guidance is in good agreement
with the track of the low. It is expected to propagate through
northwest Kansas early this afternoon and into east central
Nebraska by this evening. An incredibly strong wind field is
expected to overspread the Plains as the low rapidly deepens.
Forecast soundings continue to highlight an 850 mb jet of 60+ MPH
through the day today. It remains likely we will mix down these
higher winds. The strongest winds are likely across portions of
central and north central Kansas this afternoon where the low,
mid and upper-level jets will all be co-located and maximized.
There are indications that 70-80 MPH wind gusts will extend down
to the surface across the area. Across eastern Kansas, slightly
less wind is expected with gusts in the 60-70 MPH range.
Regardless, it will be a very windy and hazardous day. Winds will
begin to diminish around 9 PM tonight and evermore noticeably so
after midnight.
Thunderstorms...
The greatest uncertainty regarding today's forecast is the
development of thunderstorms. All ingredients should be in place
by this afternoon for thunderstorm development, however, a robust
EML will likely be in place for most of the day and could limit
convective development. There are indications that the EML will
erode enough, or that ascent along the dry line will be high
enough, to allow a narrow line of thunderstorms to develop along
the dry line as it surges across eastern Kansas. If thick cloud
cover remains over the area and temperatures fall on the low end
of expectations, then the EML may remain strong enough to inhibit
convective development. However, if everything comes together as
the CAMs suggest they will, then there is the potential for rapid
development and intensification of storms as there should be ample
instability (~1000 J/kg ML CAPE) and shear (70+ knots bulk shear)
available. Additionally, the strong low-level wind fields would
be supportive of rapidly rotating storms and therefore, there is
at least a small tornado risk should isolated storms or embedded
super-cellular structures develop. The best chance for storms
appears to be late this afternoon or early evening across eastern
Kansas and the threat window will be confined to only a couple of
hours as the dry line is expected to rapidly surge eastward and
storm motion of 60+ knots is favored.
Temperatures...
Record high temperatures are likely today (see record information
in the Climate section below). Strong warm air advection is
ongoing across the area. We likely hit our low temperature for
the night several hours ago. Temperatures have already increased
into the mid 60s across a good portion of central and eastern
Kansas. There is some uncertainty today in how much cloud cover
will be overhead and how that will impact temperatures, but there
is high confidence that we will at least see temperatures rise
into the low to mid 70s. If cloud cover is not as prevalent then
temperatures could easily climb into the upper 70s to low 80s.
The remainder of the forecast appears quiet and seasonable with
highs generally in the 50s and lows in the 20s and 30s.
&&
.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1145 AM CST Wed Dec 15 2021
Cigs between 3000-3500ft will persist into the afternoon along
with very strong south winds. Winds switch to the southwest this
evening and then to the northwest overnight as a couple of surface
boundaries move through. A quick moving line of storms looks to
impact terminals this evening with wind gusts of 60-70kts possible
as the storms move through. Skies will clear behind the storms
with winds weakening Thursday morning.
&&
.FIRE WEATHER...
Issued at 330 AM CST Wed Dec 15 2021
Critical fire weather conditions are likely today!
An extremely dangerous fire situation is likely to develop today across
most of the area. Very strong winds, sustained 30-40 mph with gusts to
70 mph are likely to combine with very low relative humidity, as low as
10 percent, behind a passing dry line. As the dry line passes from
west to east late this afternoon relative humidity will dramatically
fall behind the line. Later this evening, a cold front will swing through
from northwest to southeast. This will bring a slight recovery to humidity
and cooler temperatures. Winds will begin slowly decreasing around 9pm and
significantly wane after midnight.
&&
.CLIMATE...
Issued at 330 AM CST WED Dec 15 2021
Record Temperature Information
All-Time Record High for Dec at Topeka: 77 (1939)
All-Time Record High for Dec at Concordia: 82 (1964
All-Time Record Warm Low for Dec at Topeka: 62 (1984)
All-Time Record Warm Low for Dec at Concordia: 59 (1984)
_____________________________________
DECEMBER 15:
FORECAST LOW.....RECORD WARM LOW
Concordia 53 41 (1946)
Topeka 57 49 (1888)
FORECAST HIGH....RECORD HIGH
Concordia 71 70 (2002)
Topeka 74 70 (2002)
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
High Wind Warning until 9 PM CST this evening for KSZ008>012-
020>024-026-034>040-054>056-058-059.
Red Flag Warning until 9 PM CST this evening for KSZ008>012-
020>024-026-034>040-054-055-058.
&&
DISCUSSION...Jones
AVIATION...Flanagan
FIRE WEATHER...Jones
CLIMATE...JonesHazardous Weather Outlook National Weather Service Topeka KS 323 AM CST Wed Dec 15 2021 KSZ008>012-020>024-026-034>040-054>056-058-059-160930- Republic-Washington-Marshall-Nemaha-Brown-Cloud-Clay-Riley- Pottawatomie-Jackson-Jefferson-Ottawa-Dickinson-Geary-Morris- Wabaunsee-Shawnee-Douglas-Lyon-Osage-Franklin-Coffey-Anderson- 323 AM CST Wed Dec 15 2021 This hazardous weather outlook is for east central...north central and northeast Kansas. .DAY ONE...Today and Tonight Very strong winds, with gusts up to 70 mph, are likely today. Dangerous fire conditions are likely late this afternoon and early evening behind a passing dry line. A few severe storms are possible this afternoon and evening across eastern Kansas. If storms develop, they could produce damaging winds and possibly a tornado. See weather.gov/top for more details. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday. No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... Spotter activation may be needed late this afternoon or early this evening. && More detailed information can be accessed at... http://www.weather.gov/media/top/DssPacket.pdf AJ
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TOPEKA KS
1252 PM CST WED DEC 15 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1245 PM NON-TSTM WND GST 2 E CLAY CENTER 39.38N 97.09W
12/15/2021 M66 MPH CLAY KS MESONET
MESONET STATION EW5822 CLAY CENTER.
&&
JPPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TOPEKA KS
105 PM CST WED DEC 15 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1252 PM NON-TSTM WND GST 2 NE OGDEN 39.13N 96.68W
12/15/2021 M59 MPH RILEY KS ASOS
ASOS STATION KMHK MANHATTAN.
&&
CPPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TOPEKA KS
138 PM CST WED DEC 15 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0122 PM NON-TSTM WND GST 1 ENE LATIMER 38.74N 96.82W
12/15/2021 M58 MPH MORRIS KS MESONET
MESONET STATION UP349 1.2 E LATIMER (UPR).
&&
CPPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TOPEKA KS
200 PM CST WED DEC 15 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0152 PM NON-TSTM WND GST 2 NE OGDEN 39.13N 96.68W
12/15/2021 M61 MPH RILEY KS ASOS
&&
JPPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TOPEKA KS
204 PM CST WED DEC 15 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0153 PM NON-TSTM WND GST 1 WSW BERRYTON 38.93N 95.65W
12/15/2021 M55 MPH SHAWNEE KS ASOS
ASOS STATION KFOE TOPEKA FORBES.
&&
JPPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TOPEKA KS
227 PM CST WED DEC 15 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0202 PM NON-TSTM WND DMG ENTERPRISE 38.90N 97.12W
12/15/2021 DICKINSON KS PUBLIC
FENCE DAMAGE, 1-INCH TREE LIMBS DOWN, AND
SHINGLE DAMAGE TO A FEW HOUSES. REPORT VIA
SOCIAL MEDIA.
&&
CPThe Grand Island radar (KUEX), 75 km away, was scanning. The volume nearest the first event began at 20:25 UTC.
62 thunderstorm wind, 10 hail. Local standard time, as filed.
Large ash tree blown down and a metal basketball pole was bent in half.
Asos at kcnk recorded 67 mph wind gust.
Report of 4 inch diameter tree limbs down.
Semi truck blown over at mile marker 183 on US-81.
Asos at kcnk recorded 75 mph wind gust.
Power lines and transformer blown down.
Recroded at mesonet station k5cnc us-81.
Trained spotter reported 70 mph wind gust.
Tin roof rolled back on a building, 6 inch diameter tree limbs and a fence blown down.
Semi truck blown over at mile marker 165 on US-81.
Pea sized hail and 8 inch diameter tree blown down. Near zero visibility due to blowing dust and dirt.
Trained spotter reported a 75 mph wind gust.
Measured at mesonet station ew5822 clay center.
Two large tree limbs 8 inches in diameter blown down.
Measured at awos station kk78 Abilene.
Dead trees knocked over, 12 inches in diameter.
Damage to metal grain bins.
Measured at awos station kfri at fort riley.
Measured at mesonet station up824, 4.8 miles east of Chapman.
Report via social media picture of half of a 12 inch diameter tree blown down.
Report from public of metal signs bent, siding blown off buildings, and damage to hangers at the Junction City Airport.
Reports of severe damage from emergency manager, including motel roof blown off and into other buildings, and power outages.
Measured at asos station kmhk in Manhattan.
Report of 7 inch tree limb down.
A resident in east Manhattan shared pictures on social media of large tree braches down and reported roof shingles blown off.
Tree limbs 3 inches in diameter broken, power poles broken.
Measured at asos station kmyz at Marysville.
Measured at awos station kfri at Fort Riley.
Trees uprooted or snapped, roof blown off structure.
Report of 3 foot diameter tree blown down with the top half snapped.
Measured at mesonet station ur408, 5.5 miles northwest of Frankfort.
Roofs peeled off building, side of metal building got blown out.
Trained spotter reports 75 mph wind gust.
Trained spotted reports 70 mph wind gust.
Measured at mesonet station k5fvw us-36 at Delaware Road in Sabetha.
Tree limbs 1 inch in diameter broken, shingles blown off roof.
Report of 70 mph wind gust.
Metal pole barn blown down and completely destroyed.
Softball sized hail reported at mile marker 137 on I-35.
Quarter sized hail reported.
Tree limbs 1 inch in diameter broken, shingles blown off roof.
Tennis ball sized hail reported at I-35 and R1 east of Emporia.
Quarter sized hail.
Golf ball sized hail reported at Fanestil original plant on K-99.
Measured at kemp asos in Emporia.
Tree limbs 1 inch in diameter blown down, shingles blown off roof.
Report of several power poles snapped.
Trained spotter reported a 65 mph wind gust.
Tree limb 8 inches in diameter blown down.
Apricot sized hail reported.
Tree limbs 3 inches in diameter broken, power poles broken.
Tree limbs 3 inches in diameter broken, power poles broken.
Measured at ktop asos in Topeka.
An NWS storm survey found damage to a large farm outbuilding including partial roof and wall collapse on the structure. The survey concluded that downburst winds or 90 to 100 mph caused the damage.
Mesonet station k5006 I-470 bridge over US-75.
Tree limbs 3 inches in diameter broken, power lines broken.
EM reported 80 mph wind gust.
Mesonet station fw2032 valley falls.
Multiple power poles down, large barn blown down at Topeka and Union Street.
Large tree completely blocking road at 122nd road, one-half mile east of K4 highway.
Hen egg sized hail from photo on social media.
Golf ball sized hail reported.
Multiple power poles down, tree damage across the city of Perry.
Golf ball sized hail reported.
EM reports quarter sized hail at 4104 Delaware Rd near Pomona.
Measured at mesonet station k5007 I-70 bridge over Edgewood Road.
Report of a roof blown off of a trailer.
Small branches down, around 1 to 2 inches in diameter. Many heavy unsecured outdoor objects blown around. Power lines briefly arced together, causing quick cut to power which restored itself.
Measured at awos station kowi in Ottawa.
Measured at mesonet station up091, 1.9 miles east of Williamstown (upr).
Large tree 1 foot in diameter snapped.
Trained spotter reported 70 mph wind gust.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Kansas in 2021Every state in 2021This day in weather historyWarnings in Kansas, December 2021
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 994903, 994904, 994908, 994910, 994911, 994913, 994914, 994915, 994916, 994920, 994921, 994923, 996328, 996329, 998029, 996330, 996331, 996332, 998032, 996333, 996334, 996335, 996336, 996338, 996339, 996595, 998033, 998034, 996341, 998036, 998035, 996596, 996597, 996598, 998053, 996599, 996600, 996601, 996602, 996603, and more.