Alert archive / Colorado / Tornado Warnings in 2021

Tornado Warning 31, NWS Denver/Boulder, CO

June 19, 2021Adams County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at Jun 19, 2021, 2:52 PM MDT for Adams County, Colorado. It was in force for 23 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jun 19, 2021, 2:52 PM MDT (20:52 UTC)
Expired
Jun 19, 2021, 3:15 PM MDT
In force
23 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Tornado
Radar indicated
Hail
1.0 in

County Adams County, CO

The radar

The Denver radar (KFTG), 59 km from the middle of the area, began a volume at 20:55 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.

The watch it was issued in

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

IssuedProductOfficeLasted
Jun 19, 1:44 PM MDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 8.9 hours before the alert went out and 55 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 2021-06-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 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 2021-06-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -23 square meters per square second.193958Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2627 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
-23 m²/s²
0-3 km storm-relative helicity
44 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

281 
WFUS55 KBOU 192052
TORBOU
COC001-192115-
/O.NEW.KBOU.TO.W.0031.210619T2052Z-210619T2115Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Denver CO
252 PM MDT Sat Jun 19 2021

The National Weather Service in Denver Colorado has issued a

* Tornado Warning for...
  Northeastern Adams County in northeastern Colorado...

* Until 315 PM MDT.
    
* At 251 PM MDT, a severe thunderstorm capable of producing a tornado
  was located near Shamrock, or 27 miles south of Fort Morgan, moving
  northeast at 15 mph.

  HAZARD...Tornado and quarter size hail.

  SOURCE...Radar indicated rotation.

  IMPACT...Expect damage to mobile homes, roofs, and vehicles.

* Locations impacted include...
  Shamrock.

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 3979 10396 4000 10401 4000 10371 3979 10371
TIME...MOT...LOC 2051Z 222DEG 13KT 3987 10387 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

RPK
2 follow-up statements
047 
WWUS55 KBOU 192104
SVSBOU

Severe Weather Statement
National Weather Service Denver CO
304 PM MDT Sat Jun 19 2021

COC001-192115-
/O.CON.KBOU.TO.W.0031.000000T0000Z-210619T2115Z/
Adams CO-
304 PM MDT Sat Jun 19 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 315 PM MDT FOR
NORTHEASTERN ADAMS COUNTY...
    
At 304 PM MDT, a severe thunderstorm capable of producing a tornado
was located over Shamrock, or 24 miles south of Fort Morgan, moving
east at 15 mph.

HAZARD...TORNADO and quarter size hail.

SOURCE...Radar indicated rotation.

IMPACT...Expect damage to mobile homes, roofs, and vehicles.

Locations impacted include...
Shamrock.

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 3982 10396 4000 10396 4000 10371 3982 10371
TIME...MOT...LOC 2104Z 252DEG 11KT 3990 10383 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

RPK
606 
WWUS55 KBOU 192111 RRA
SVSBOU

Severe Weather Statement
National Weather Service Denver CO
311 PM MDT Sat Jun 19 2021

COC001-192121-
/O.EXP.KBOU.TO.W.0031.000000T0000Z-210619T2115Z/
Adams CO-
311 PM MDT Sat Jun 19 2021

...THE TORNADO WARNING FOR NORTHEASTERN ADAMS COUNTY WILL EXPIRE AT
315 PM MDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning will be allowed to expire.  However small
hail, gusty winds and heavy rain are still possible with this
thunderstorm.

A Severe Thunderstorm Watch remains in effect until 900 PM MDT for
northeastern Colorado.

LAT...LON 3982 10396 4000 10396 4000 10371 3982 10371
TIME...MOT...LOC 2111Z 222DEG 13KT 3991 10381 

$$

RPK

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 18, 8:57 PM MDTSevere Thunderstorm WarningBOUWeld33 min
Jun 19, 11:54 AM MDTFire Weather WatchBOUGrand, Jackson, Summit15 hr
Jun 19, 1:25 PM MDTSpecial Weather StatementBOUArapahoe35 min
Jun 19, 1:57 PM MDTSpecial Weather StatementBOUDenver33 min
Jun 19, 2:09 PM MDTTornado Warning Tornado observedBOUAdams36 min
Jun 19, 2:40 PM MDTTornado WarningBOUMorgan35 min
Jun 19, 2:54 PM MDTTornado WarningBOUElbert21 min
Jun 19, 3:14 PM MDTSevere Thunderstorm WarningBOUWeld31 min
Jun 19, 3:26 PM MDTSevere Thunderstorm WarningBOUAdams, Washington34 min
Jun 19, 3:33 PM MDTSevere Thunderstorm WarningBOUWashington27 min
Jun 19, 3:35 PM MDTSpecial Weather StatementBOUWashington55 min
Jun 19, 3:41 PM MDTSevere Thunderstorm WarningBOUElbert, Lincoln49 min
Jun 19, 3:55 PM MDTSevere Thunderstorm WarningBOUWashington50 min
Jun 19, 4:04 PM MDTSevere Thunderstorm WarningBOULogan41 min
Jun 19, 4:09 PM MDTSevere Thunderstorm WarningBOULincoln51 min
Jun 19, 4:12 PM MDTTornado WarningBOUWashington33 min
Jun 19, 4:15 PM MDTTornado WarningBOULogan30 min
Jun 19, 4:37 PM MDTSevere Thunderstorm WarningBOUWashington38 min
Jun 19, 4:49 PM MDTSevere Thunderstorm WarningBOULogan, Phillips, Sedgwick41 min
Jun 19, 4:57 PM MDTSevere Thunderstorm WarningBOULincoln33 min
Jun 19, 5:16 PM MDTSevere Thunderstorm WarningBOUPhillips, Sedgwick29 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.