Alert archive / Colorado / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 118, NWS Denver/Boulder, CO

August 7, 2021Lincoln County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Aug 7, 2021, 2:29 PM MDT for Lincoln County, Colorado. It was in force for 33 min. 1 report 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 7, 2021, 2:29 PM MDT (20:29 UTC)
Expired
Aug 7, 2021, 3:02 PM MDT
In force
33 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Lincoln County, CO

The radar

The Pueblo radar (KPUX), 85 km from the middle of the area, began a volume at 20:31 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
Aug 7, 2:30 PM MDTHAIL 1.256 W Boyero, CO

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, 8.5 hours before the alert went out and 108 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 2021-08-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 90 joules per kilogram.LCLLFCEL10008507005003002001001 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 2021-08-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 18 square meters per square second.19395878Sfc1 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
90 J/kg
Mixed-layer CIN
-282 J/kg
Mixed-layer LCL
2495 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
18 m²/s²
0-3 km storm-relative helicity
114 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

880 
WUUS55 KBOU 072029
SVRBOU
COC073-072115-
/O.NEW.KBOU.SV.W.0118.210807T2029Z-210807T2115Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Denver CO
229 PM MDT Sat Aug 7 2021

The National Weather Service in Denver Colorado has issued a

* Severe Thunderstorm Warning for...
  East central Lincoln County in east central Colorado...

* Until 315 PM MDT.

* At 229 PM MDT, a severe thunderstorm was located 8 miles west of
  Boyero, or 27 miles southeast of Limon, moving east at 25 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees. Hail damage to 
           vehicles is expected.

* Locations impacted include...
  Boyero.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3884 10351 3893 10353 3902 10346 3902 10332
      3897 10317 3872 10317
TIME...MOT...LOC 2029Z 291DEG 22KT 3893 10342 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

RJK
2 follow-up statements
249 
WWUS55 KBOU 072045
SVSBOU

Severe Weather Statement
National Weather Service Denver CO
245 PM MDT Sat Aug 7 2021

COC073-072115-
/O.CON.KBOU.SV.W.0118.000000T0000Z-210807T2115Z/
Lincoln CO-
245 PM MDT Sat Aug 7 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 315 PM MDT
FOR EAST CENTRAL LINCOLN COUNTY...

At 244 PM MDT, a severe thunderstorm was located over Boyero, or 28
miles south of Flagler, moving east at 30 mph.

HAZARD...Half dollar size hail.

SOURCE...Trained weather spotters.

IMPACT...Damage to vehicles is expected.

Locations impacted include...
Boyero.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3881 10331 3888 10337 3896 10335 3900 10328
      3897 10317 3878 10317
TIME...MOT...LOC 2044Z 286DEG 24KT 3891 10327 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.25 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...<50 MPH

$$

RJK
551 
WWUS55 KBOU 072102
SVSBOU

Severe Weather Statement
National Weather Service Denver CO
302 PM MDT Sat Aug 7 2021

COC073-072110-
/O.CAN.KBOU.SV.W.0118.000000T0000Z-210807T2115Z/
Lincoln CO-
302 PM MDT Sat Aug 7 2021

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL LINCOLN COUNTY IS
CANCELLED...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning has been cancelled.  The storm produced 1.25 
inch hail at 2:30 PM MDT 6 miles west of Boyero in Lincoln County.

LAT...LON 3881 10331 3888 10337 3896 10335 3900 10328
      3897 10317 3878 10317
TIME...MOT...LOC 2059Z 291DEG 22KT 3887 10315 

$$

RJK

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 6, 6:15 PM MDTSpecial Weather StatementBOULogan45 min
Aug 6, 6:24 PM MDTSpecial Weather StatementBOUJackson36 min
Aug 6, 6:53 PM MDTFlash Flood WarningBOULarimer2 hr
Aug 6, 7:36 PM MDTSpecial Weather StatementBOULarimer24 min
Aug 6, 7:58 PM MDTAreal Flood AdvisoryBOULarimer2 hr
Aug 6, 10:06 PM MDTAreal Flood AdvisoryBOULarimer84 min
Aug 7, 1:08 PM MDTSpecial Weather StatementBOULincoln52 min
Aug 7, 1:48 PM MDTSevere Thunderstorm WarningBOUElbert, Lincoln42 min

Nearby

Severe Thunderstorm Warnings in Colorado, 2021Every severe thunderstorm warning 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.