Alert archive / Colorado / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 235, NWS Goodland, KS

September 12, 2021Cheyenne County, Colorado

NWS Goodland, KS issued this severe thunderstorm warning at Sep 12, 2021, 6:37 PM MDT for Cheyenne County, Colorado. It was in force for 53 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
Sep 12, 2021, 6:37 PM MDT (00:37 UTC)
Expired
Sep 12, 2021, 7:30 PM MDT
In force
53 min
Issued by
NWS Goodland, KS
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Cheyenne County, CO

The radar

The Goodland radar (KGLD), 95 km from the middle of the area, began a volume at 00:41 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

TimeReportWhereRemark
Sep 12, 6:44 PM MDTTSTM WND GST 532 Sw Firstview, CO
Sep 12, 6:55 PM MDTHAIL 0.251 W Cheyenne Wells, COSPOTTER REPORTED PEA SIZE HAIL AND HEAVY RAIN.

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 00:00Z, 0.6 hours before the alert went out and 123 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 00:00Z on 2021-09-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1 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 00:00Z on 2021-09-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -12 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
1 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2604 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
-12 m²/s²
0-3 km storm-relative helicity
74 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

360 
WUUS53 KGLD 130037
SVRGLD
COC017-130130-
/O.NEW.KGLD.SV.W.0235.210913T0037Z-210913T0130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Goodland KS
637 PM MDT Sun Sep 12 2021

The National Weather Service in Goodland has issued a

* Severe Thunderstorm Warning for...
  Cheyenne County in east central Colorado...

* Until 730 PM MDT.

* At 637 PM MDT, a severe thunderstorm was located 12 miles northeast
  of Kit Carson, or 13 miles west of Cheyenne Wells, moving east at
  40 mph.

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

  SOURCE...Radar indicated.

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

* This severe thunderstorm will be near...
  Cheyenne Wells around 655 PM MDT.

This includes Highway 385 between mile markers 136 and 169.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3904 10295 3905 10205 3862 10205 3862 10300
TIME...MOT...LOC 0037Z 265DEG 36KT 3885 10260 

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

$$

TT
4 follow-up statements
459 
WWUS53 KGLD 130052
SVSGLD

Severe Weather Statement
National Weather Service Goodland KS
652 PM MDT Sun Sep 12 2021

COC017-130130-
/O.CON.KGLD.SV.W.0235.000000T0000Z-210913T0130Z/
Cheyenne CO-
652 PM MDT Sun Sep 12 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 730 PM MDT
FOR CHEYENNE COUNTY IN EAST CENTRAL COLORADO...

At 652 PM MDT, a severe thunderstorm was located near Cheyenne Wells,
moving east at 35 mph.

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

SOURCE...Radar indicated.

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

This severe thunderstorm will remain over mainly rural areas of
Cheyenne County in east central Colorado, including the following
locations... Arapahoe and Firstview.

This includes Highway 385 between mile markers 136 and 169.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3904 10281 3905 10205 3862 10205 3862 10289
TIME...MOT...LOC 0052Z 273DEG 32KT 3882 10231 

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

$$

TT
467 
WWUS53 KGLD 130105
SVSGLD

Severe Weather Statement
National Weather Service Goodland KS
705 PM MDT Sun Sep 12 2021

COC017-130130-
/O.CON.KGLD.SV.W.0235.000000T0000Z-210913T0130Z/
Cheyenne CO-
705 PM MDT Sun Sep 12 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 730 PM MDT
FOR EASTERN CHEYENNE COUNTY IN EAST CENTRAL COLORADO...

At 704 PM MDT, a severe thunderstorm was located 10 miles west of
Weskan, or 10 miles east of Cheyenne Wells, moving east at 40 mph.

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

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Cheyenne Wells, Arapahoe and Firstview. 

This includes Highway 385 between mile markers 136 and 160.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3890 10257 3905 10205 3862 10205 3862 10274
TIME...MOT...LOC 0104Z 265DEG 36KT 3883 10215 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

TT
088 
WWUS53 KGLD 130119
SVSGLD

Severe Weather Statement
National Weather Service Goodland KS
719 PM MDT Sun Sep 12 2021

COC017-130130-
/O.CON.KGLD.SV.W.0235.000000T0000Z-210913T0130Z/
Cheyenne CO-
719 PM MDT Sun Sep 12 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 730 PM MDT
FOR SOUTHEASTERN CHEYENNE COUNTY IN EAST CENTRAL COLORADO...

At 718 PM MDT, a severe thunderstorm was located 13 miles northwest
of Towner, or 15 miles southeast of Cheyenne Wells, moving southeast
at 35 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Cheyenne Wells and Arapahoe. 

This includes Highway 385 between mile markers 136 and 154.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3883 10248 3899 10205 3862 10205 3862 10265
TIME...MOT...LOC 0118Z 317DEG 32KT 3864 10219 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

TT
704 
WWUS53 KGLD 130126
SVSGLD

Severe Weather Statement
National Weather Service Goodland KS
726 PM MDT Sun Sep 12 2021

COC017-130135-
/O.EXP.KGLD.SV.W.0235.000000T0000Z-210913T0130Z/
Cheyenne CO-
726 PM MDT Sun Sep 12 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN CHEYENNE COUNTY
IN EAST CENTRAL COLORADO WILL EXPIRE AT 730 PM MDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However gusty
winds are still possible with this thunderstorm.

LAT...LON 3883 10248 3899 10205 3862 10205 3862 10265
TIME...MOT...LOC 0125Z 265DEG 36KT 3865 10211 

$$

TT

The office that day

Everything else NWS Goodland, KS issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 12, 7:07 PM MDTSpecial Weather StatementGLDKit Carson23 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.