Alert archive / Nebraska / Tornado Warnings in 2021

Tornado Warning 9, NWS Omaha, NE

August 20, 2021Jefferson County, Nebraska

NWS Omaha, NE issued this tornado warning at Aug 20, 2021, 5:41 PM CDT for Jefferson County, Nebraska. It was in force for 34 min. 4 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Aug 20, 2021, 5:41 PM CDT (22:41 UTC)
Expired: Aug 20, 2021, 6:15 PM CDT
In force: 34 min
Issued by: NWS Omaha, NE
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

County Jefferson County, NE

The radar

The Grand Island radar (KUEX), 104 km from the middle of the area, began a volume at 22:41 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.

What was reported inside it

Time	Report	Where	Remark
Aug 20, 5:47 PM CDT	FUNNEL CLOUD	6 Nnw Fairbury, NE	DELAYED REPORT: STANDING AT THE CORNER OF 565TH AVE AND 717TH ROAD... LOOKING SOUTHWEST. SAW A FUNNEL ABOUT HALFWAY DOWN TO THE GROUND. IT NEVER DID TOUCH DOWN.
Aug 20, 5:53 PM CDT	TSTM WND GST 50	1 Wnw Fairbury, NE	50 MPH MEASURED BY EMERGENCY MANAGER.
Aug 20, 5:59 PM CDT	TSTM WND GST 54	2 Wsw Fairbury, NE	MESONET STATION CW6705 FAIRBURY.
Aug 20, 6:01 PM CDT	HAIL 0.7	1 Wnw Fairbury, NE	PEA TO DIME SIZED.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

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

Issued	Product	Office	Lasted
Aug 20, 4:39 PM CDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 10.7 hours before the alert went out and 152 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 950 J/kg
Mixed-layer CIN: -4 J/kg
Mixed-layer LCL: 534 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 121 m²/s²
0-3 km storm-relative helicity: 99 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

733 
WFUS53 KOAX 202241
TOROAX
NEC095-202315-
/O.NEW.KOAX.TO.W.0009.210820T2241Z-210820T2315Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Omaha/Valley Nebraska
541 PM CDT Fri Aug 20 2021

The National Weather Service in Omaha has issued a

* Tornado Warning for...
  Southwestern Jefferson County in southeastern Nebraska...

* Until 615 PM CDT.
    
* At 540 PM CDT, a severe thunderstorm capable of producing a tornado
  was located near Gilead, or 27 miles northwest of Washington,
  moving east at 20 mph.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* This dangerous storm will be near...
  Fairbury around 555 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4004 9737 4023 9737 4025 9706 4004 9703
TIME...MOT...LOC 2240Z 271DEG 34KT 4015 9733 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

Mead

2 follow-up statements

754 
WWUS53 KOAX 202254
SVSOAX

Severe Weather Statement
National Weather Service Omaha/Valley Nebraska
554 PM CDT Fri Aug 20 2021

NEC095-202315-
/O.CON.KOAX.TO.W.0009.000000T0000Z-210820T2315Z/
Jefferson NE-
554 PM CDT Fri Aug 20 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 615 PM CDT FOR
SOUTHWESTERN JEFFERSON COUNTY...
    
At 554 PM CDT, a severe thunderstorm capable of producing a tornado
was located over Fairbury, or 24 miles northwest of Washington,
moving east at 20 mph.

HAZARD...Tornado and golf ball size hail.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

Locations impacted include...
Fairbury, Endicott, Jansen, Reynolds, Crystal Springs Campground,
Buckley Creek Recreational Area, Camp Jefferson, Alexandria State
Recreation Area and Rock Creek Station State Historical Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4004 9737 4023 9737 4025 9706 4004 9703
TIME...MOT...LOC 2254Z 270DEG 30KT 4015 9723 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...1.75 IN

$$

Mead

946 
WWUS53 KOAX 202310
SVSOAX

Severe Weather Statement
National Weather Service Omaha/Valley Nebraska
610 PM CDT Fri Aug 20 2021

NEC095-202319-
/O.EXP.KOAX.TO.W.0009.000000T0000Z-210820T2315Z/
Jefferson NE-
610 PM CDT Fri Aug 20 2021

...THE TORNADO WARNING FOR SOUTHWESTERN JEFFERSON COUNTY WILL EXPIRE
AT 615 PM CDT...
    
The tornado threat has diminished and the Tornado Warning has been
cancelled. However, large hail and damaging winds remain likely and a
Severe Thunderstorm Warning remains in effect for the area.

A Severe Thunderstorm Watch remains in effect until 1100 PM CDT for
southeastern Nebraska.

Remember, a Severe Thunderstorm Warning still remains in effect for 
parts of Jefferson County until 645 PM CDT.

LAT...LON 4004 9737 4023 9737 4025 9706 4004 9703
TIME...MOT...LOC 2309Z 271DEG 34KT 4015 9706 

$$

Mead

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 20, 6:08 PM CDT	Severe Thunderstorm Warning	OAX	Jefferson	21 min
Aug 20, 6:27 PM CDT	Special Weather Statement	OAX	Gage	33 min

Nearby

Tornado Warnings in Nebraska, 2021 Every tornado warning in 2021 Tornadoes in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.