Alert archive / Colorado / Tornado Warnings in 2001

Tornado Warning 30, NWS Denver/Boulder, CO

June 20, 2001Arapahoe County, Elbert County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at Jun 20, 2001, 8:08 PM MDT for Arapahoe County, Elbert County, Colorado. It was in force for 37 min. 3 reports came from inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties, with what was reported inside it.

The facts

Issued: Jun 20, 2001, 8:08 PM MDT (02:08 UTC)
Expired: Jun 20, 2001, 8:45 PM MDT
In force: 37 min
Issued by: NWS Denver/Boulder, CO
Area: Whole counties; the outline is the Mesonet’s reconstruction

Counties Arapahoe County, CO, Elbert County, CO

The radar

The Denver radar (KFTG), 36 km from the middle of the area, began a volume at 02:09 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
Jun 20, 8:10 PM MDT	Tornado F0	Kiowa, CO	A tornado touched down briefly. Bark was ripped off trees and several large limbs were snapped off. An alfalfa field was also damaged. The combination of strong winds and hail caused extensive damage to the siding of a nearby house. One of the windows was
Jun 20, 8:32 PM MDT	Hail 1.75	Kiowa, CO
Jun 20, 8:35 PM MDT	Hail 2.5	Kiowa, CO

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The watch it was issued in

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

Issued	Product	Office	Lasted
Jun 20, 3:30 PM MDT	Tornado Watch	SPC	6 hr

The nearest sounding before it

Denver, CO (KDNR), launched 00:00Z, 2.1 hours before the alert went out and 114 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: 484 J/kg
Mixed-layer CIN: -46 J/kg
Mixed-layer LCL: 1925 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: -40 m²/s²
0-3 km storm-relative helicity: 207 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 2.5

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WFUS55 KBOU 210211
TORDEN

COC005-039-210245-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DENVER CO
808 PM MDT WED JUN 20 2001

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHWESTERN ELBERT COUNTY IN EAST CENTRAL COLORADO
  SOUTH CENTRAL ARAPAHOE COUNTY IN NORTHEAST COLORADO

* UNTIL 845 PM MDT

* AT 808 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  THUNDERSTORM WITH A POSSIBLE TORNADO OVER SOUTH CENTRAL ARAPAHOE   
  COUNTY...OR ABOUT 26 MILES EAST OF DENVER...MOVING SOUTH AT 30 MPH.

THIS WARNING REPLACES THE EARLIER WARNING FOR ADAMS AND ARAPAHOE 
COUNTY.  THIS IS A DANGEROUS SITUATION WITH EXTREMELY LARGE HAIL AND 
A POSSIBLE LARGE AND DAMAGING TORNADO.  

THE SAFEST PLACE TO BE DURING A TORNADO IS IN A BASEMENT. GET UNDER A
WORKBENCH OR OTHER PIECE OF STURDY FURNITURE. IF NO BASEMENT IS
AVAILABLE...SEEK SHELTER ON THE LOWEST FLOOR OF THE BUILDING IN AN
INTERIOR HALLWAY OR ROOM SUCH AS A CLOSET. USE BLANKETS OR PILLOWS TO
COVER YOUR BODY AND ALWAYS STAY AWAY FROM WINDOWS.

IF IN MOBILE HOMES OR VEHICLES...EVACUATE THEM AND GET INSIDE A
SUBSTANTIAL SHELTER. IF NO SHELTER IS AVAgILABLE...LIE FLAT IN THE
NEAREST DITCH OR OTHER LOW SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

LAT...LON 3939 10458 3936 10419 3961 10429 3961 10462

The office that day

Everything else NWS Denver/Boulder, CO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 20, 6:25 PM MDT	Tornado Warning	BOU	Lincoln	35 min
Jun 20, 6:32 PM MDT	Severe Thunderstorm Warning	BOU	Weld	43 min
Jun 20, 7:02 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Denver	43 min
Jun 20, 7:02 PM MDT	Severe Thunderstorm Warning	BOU	Weld	43 min
Jun 20, 7:11 PM MDT	Tornado Warning	BOU	Adams, Denver	34 min
Jun 20, 7:15 PM MDT	Severe Thunderstorm Warning	BOU	Lincoln	45 min
Jun 20, 7:32 PM MDT	Tornado Warning	BOU	Adams, Arapahoe, Denver	28 min
Jun 20, 7:47 PM MDT	Tornado Warning	BOU	Adams, Arapahoe, Denver	33 min
Jun 20, 8:33 PM MDT	Tornado Warning	BOU	Elbert	37 min
Jun 20, 9:11 PM MDT	Severe Thunderstorm Warning	BOU	Elbert	29 min

Nearby

Tornado Warnings in Colorado, 2001 Every tornado warning in 2001 Tornadoes in 2001

Sources

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