Alert archive / Colorado / Tornado Warnings in 2021

Tornado Warning 28, NWS Denver/Boulder, CO

June 7, 2021Weld County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at Jun 7, 2021, 5:24 PM MDT for Weld County, Colorado. It was in force for 36 min. 2 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
Jun 7, 2021, 5:24 PM MDT (23:24 UTC)
Expired
Jun 7, 2021, 6:00 PM MDT
In force
36 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Tornado
Observed
Hail
0.0 in

County Weld County, CO

The radar

The Denver radar (KFTG), 55 km from the middle of the area, began a volume at 23:27 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

TimeReportWhereRemark
Jun 7, 5:24 PM MDTTORNADO3 Wsw Platteville, COTORNADO DAMAGE AT HIGHWAY 66 AND WELD COUNTY ROAD 21. POWER LINES AND POWER POLES DOWN. STRUCTURE FIRE DUE TO DOWNED POWER LINES.
Jun 7, 5:32 PM MDTTORNADO3 Nw Of Platteville, COTORNADO DISSIPATED AT THIS TIME.

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

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 11.4 hours before the alert went out and 144 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-pSkew-T log-p diagram, Denver, CO at 12:00Z on 2021-06-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 17 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 12:00Z on 2021-06-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -1 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
17 J/kg
Mixed-layer CIN
-372 J/kg
Mixed-layer LCL
2991 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
-1 m²/s²
0-3 km storm-relative helicity
-2 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

000 
WFUS55 KBOU 072324
TORBOU
COC123-080000-
/O.NEW.KBOU.TO.W.0028.210607T2324Z-210608T0000Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Denver CO
524 PM MDT Mon Jun 7 2021

The National Weather Service in Denver Colorado has issued a

* Tornado Warning for...
  Southwestern Weld County in northeastern Colorado...

* Until 600 PM MDT.

* At 524 PM MDT, a confirmed tornado was located near Platteville, or
  15 miles southwest of Greeley, moving northeast at 10 mph.

  HAZARD...Damaging tornado.

  SOURCE...Weather spotters confirmed tornado.

  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...
  Firestone, Milliken, Mead, Platteville and Gilcrest. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To repeat, a tornado is on the ground. 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 4013 10492 4024 10497 4029 10492 4032 10480
      4024 10476 4016 10474
TIME...MOT...LOC 2324Z 203DEG 8KT 4022 10487 

TORNADO...OBSERVED
HAIL...0.00IN

$$

RJK
2 follow-up statements
828 
WWUS55 KBOU 072349
SVSBOU

Severe Weather Statement
National Weather Service Denver CO
549 PM MDT Mon Jun 7 2021

COC123-080000-
/O.CON.KBOU.TO.W.0028.000000T0000Z-210608T0000Z/
Weld CO-
549 PM MDT Mon Jun 7 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 600 PM MDT FOR
SOUTHWESTERN WELD COUNTY...
    
At 548 PM MDT, radar was indicating a possible tornado located 4 
miles northwest of Platteville, or about 10 miles southwest of 
Greeley, moving northeast at 10 mph.

This storm has produced a tornado but it has lifted at the current 
time.  A tornado is still possible with this storm so the warning 
still remains in effect until 600 PM MDT.

HAZARD...Damaging tornado.

SOURCE...Weather spotters confirmed tornado.

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...
Milliken, Mead, Platteville and Gilcrest. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To repeat, a tornado is on the ground. 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 4017 10492 4024 10497 4029 10492 4032 10480
      4024 10476 4017 10478
TIME...MOT...LOC 2345Z 203DEG 7KT 4025 10485 

TORNADO...OBSERVED
HAIL...0.00IN

$$

RJK
901 
WWUS55 KBOU 080003
SVSBOU

Severe Weather Statement
National Weather Service Denver CO
603 PM MDT Mon Jun 7 2021

COC123-080010-
/O.EXP.KBOU.TO.W.0028.000000T0000Z-210608T0000Z/
Weld CO-
603 PM MDT Mon Jun 7 2021

...THE TORNADO WARNING FOR SOUTHWESTERN WELD COUNTY HAS EXPIRED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning has been allowed to expire.

The only reports of damage from the tornado, so far, were power 
poles down 3 miles west-southwest of Platteville near highway 66 and 
Weld county Road 21.    

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Denver Colorado.

LAT...LON 4017 10492 4024 10497 4029 10492 4032 10480
      4024 10476 4017 10478
TIME...MOT...LOC 0000Z 208DEG 10KT 4029 10482 

$$

RJK

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 7, 5:07 PM MDTTornado WarningBOUWeld23 min

Nearby

Tornado Warnings in Colorado, 2021Every tornado warning in 2021Tornadoes 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.