Alert archive / Colorado / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 126, NWS Denver/Boulder, CO

August 14, 2021Phillips County, Sedgwick County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Aug 14, 2021, 9:15 PM MDT for Phillips County, Sedgwick County, Colorado. It was in force for 14 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
Aug 14, 2021, 9:15 PM MDT (03:15 UTC)
Expired
Aug 14, 2021, 9:29 PM MDT
In force
14 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Hail
1.0 in
Wind
50.0 mph

Counties Phillips County, CO, Sedgwick County, CO

The radar

The Goodland radar (KGLD), 169 km from the middle of the area, began a volume at 03:18 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
Aug 14, 3:28 PM MDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Denver, CO (KDNR), launched 00:00Z, 3.3 hours before the alert went out and 111 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 2021-08-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 666 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 2021-08-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -22 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
666 J/kg
Mixed-layer CIN
-45 J/kg
Mixed-layer LCL
3335 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
-22 m²/s²
0-3 km storm-relative helicity
81 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.4

Open this sounding in Storm Lab

The text

As transmitted.

617 
WUUS55 KBOU 150315
SVRBOU
COC095-115-150400-
/O.NEW.KBOU.SV.W.0126.210815T0315Z-210815T0400Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Denver CO
915 PM MDT Sat Aug 14 2021

The National Weather Service in Denver Colorado has issued a

* Severe Thunderstorm Warning for...
  Northwestern Phillips County in northeastern Colorado...
  Southwestern Sedgwick County in northeastern Colorado...

* Until 1000 PM MDT.

* At 914 PM MDT, a severe thunderstorm was located near Marks Butte, 
  or 19 miles southwest of Julesburg, moving southwest at 20 mph.

  HAZARD...Quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Damage to vehicles is expected.

* Locations impacted include...
  Fairfield and Haxtun.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4089 10261 4084 10239 4058 10249 4059 10266
      4061 10267
TIME...MOT...LOC 0314Z 024DEG 18KT 4081 10254 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...<50 MPH

$$

BARJENBRUCH
1 follow-up statement
821 
WWUS55 KBOU 150329
SVSBOU

Severe Weather Statement
National Weather Service Denver CO
929 PM MDT Sat Aug 14 2021

COC095-115-150338-
/O.CAN.KBOU.SV.W.0126.000000T0000Z-210815T0400Z/
Phillips CO-Sedgwick CO-
929 PM MDT Sat Aug 14 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN PHILLIPS AND
SOUTHWESTERN SEDGWICK COUNTIES IS CANCELLED...
                
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 has been cancelled.

A Severe Thunderstorm Watch remains in effect until 1100 PM MDT for
northeastern Colorado.

LAT...LON 4089 10261 4084 10239 4058 10249 4059 10266
      4061 10267
TIME...MOT...LOC 0328Z 024DEG 18KT 4074 10258 

$$

BARJENBRUCH

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 14, 6:48 PM MDTFlash Flood WarningBOULarimer115 min
Aug 14, 7:15 PM MDTSpecial Weather StatementBOUSummit30 min
Aug 14, 7:38 PM MDTSevere Thunderstorm Warning Considerable damage threatBOUWeld52 min
Aug 14, 8:01 PM MDTSevere Thunderstorm Warning Considerable damage threatBOULogan44 min
Aug 14, 8:28 PM MDTSevere Thunderstorm WarningBOUWeld47 min
Aug 14, 8:29 PM MDTSevere Thunderstorm WarningBOUSedgwick46 min
Aug 14, 8:43 PM MDTSevere Thunderstorm Warning Considerable damage threatBOULogan, Washington47 min
Aug 14, 9:28 PM MDTSevere Thunderstorm WarningBOULogan, Washington47 min
Aug 14, 9:31 PM MDTSpecial Weather StatementBOUWeld44 min
Aug 15, 2:32 PM MDTAreal Flood AdvisoryBOUGrand88 min
Aug 15, 5:19 PM MDTSpecial Weather StatementBOULincoln41 min
Aug 15, 5:25 PM MDTSpecial Weather StatementBOUTeller65 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.