Alert archive / Colorado / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 100, NWS Denver/Boulder, CO

July 3, 2021Washington County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Jul 3, 2021, 5:56 PM MDT for Washington County, Colorado. It was in force for 34 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
Jul 3, 2021, 5:56 PM MDT (23:56 UTC)
Expired
Jul 3, 2021, 6:30 PM MDT
In force
34 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Hail
2.0 in
Wind
60.0 mph

County Washington County, CO

The radar

The Goodland radar (KGLD), 119 km from the middle of the area, began a volume at 23:56 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
Jul 3, 6:01 PM MDTTSTM WND GST 609 E Elba, COWA159, BRANCHES BREAKING.

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

The watch it was issued in

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

IssuedProductOfficeLasted
Jul 3, 3:33 PM MDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 11.9 hours before the alert went out and 32 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 2021-07-03Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 12:00Z on 2021-07-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 26 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
2605 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
26 m²/s²
0-3 km storm-relative helicity
31 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

128 
WUUS55 KBOU 032356
SVRBOU
COC121-040030-
/O.NEW.KBOU.SV.W.0100.210703T2356Z-210704T0030Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Denver CO
556 PM MDT Sat Jul 3 2021

The National Weather Service in Denver Colorado has issued a

* Severe Thunderstorm Warning for...
  Southeastern Washington County in northeastern Colorado...

* Until 630 PM MDT.

* At 556 PM MDT, a severe thunderstorm was located 14 miles north of
  Arickaree School, or 17 miles southwest of Yuma, moving southeast
  at 15 mph.

  HAZARD...Two inch hail and 60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees. People and 
           animals outdoors will be injured. Expect hail damage to 
           roofs, siding, windows, and vehicles.

* Locations impacted include...
  Arickaree School.

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 4000 10280 3998 10281 3980 10280 3973 10305
      4000 10314 4008 10280 4000 10279
TIME...MOT...LOC 2356Z 335DEG 12KT 3994 10294 

HAIL...2.00IN
WIND...60MPH
 
$$

RPK
1 follow-up statement
906 
WWUS55 KBOU 040026
SVSBOU

Severe Weather Statement
National Weather Service Denver CO
626 PM MDT Sat Jul 3 2021

COC121-040036-
/O.EXP.KBOU.SV.W.0100.000000T0000Z-210704T0030Z/
Washington CO-
626 PM MDT Sat Jul 3 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN WASHINGTON COUNTY
WILL EXPIRE AT 630 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 small
hail, gusty winds and heavy rain are still possible with this
thunderstorm.

A Severe Thunderstorm Watch remains in effect until 1000 PM MDT for
northeastern Colorado.

LAT...LON 4000 10280 3998 10281 3980 10280 3973 10305
      4000 10314 4008 10280 4000 10279
TIME...MOT...LOC 0026Z 335DEG 12KT 3986 10289 

$$

RPK

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 2, 6:36 PM MDTSpecial Weather StatementBOUDenver24 min
Jul 2, 6:42 PM MDTSevere Thunderstorm WarningBOUAdams, Weld33 min
Jul 2, 7:11 PM MDTAreal Flood AdvisoryBOUAdams47 min
Jul 2, 7:13 PM MDTSpecial Weather StatementBOUDenver32 min
Jul 2, 7:17 PM MDTAreal Flood AdvisoryBOULarimer88 min
Jul 3, 2:03 PM MDTAreal Flood AdvisoryBOULarimer87 min
Jul 3, 2:22 PM MDTSpecial Weather StatementBOUWeld38 min
Jul 3, 3:11 PM MDTSpecial Weather StatementBOUWeld34 min
Jul 3, 3:23 PM MDTSevere Thunderstorm WarningBOUWeld37 min
Jul 3, 3:57 PM MDTSevere Thunderstorm WarningBOUMorgan, Weld33 min
Jul 3, 4:25 PM MDTSpecial Weather StatementBOULogan20 min
Jul 3, 4:34 PM MDTSpecial Weather StatementBOULogan26 min
Jul 3, 4:45 PM MDTSpecial Weather StatementBOUMorgan30 min
Jul 3, 4:53 PM MDTSevere Thunderstorm WarningBOUWashington37 min
Jul 3, 4:59 PM MDTSevere Thunderstorm WarningBOULogan31 min
Jul 3, 5:05 PM MDTSevere Thunderstorm WarningBOULogan25 min
Jul 3, 5:14 PM MDTSpecial Weather StatementBOUElbert31 min
Jul 3, 5:20 PM MDTSevere Thunderstorm WarningBOUElbert25 min
Jul 3, 5:29 PM MDTSevere Thunderstorm WarningBOUWashington31 min
Jul 3, 5:38 PM MDTAreal Flood AdvisoryBOULogan82 min
Jul 3, 5:40 PM MDTAreal Flood AdvisoryBOUElbert95 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.