Severe Thunderstorm Warning 128, NWS Denver/Boulder, CO

Issued

Aug 19, 2021, 2:24 PM MDT (20:24 UTC)

Expired

Aug 19, 2021, 3:00 PM MDT

In force

36 min

Issued by

NWS Denver/Boulder, CO

Area

Storm-based polygon

Damage threat

Considerable

Hail

1.75 in

Wind

60.0 mph

Counties Boulder County, CO, Broomfield County, CO, Jefferson County, CO

The Denver radar (KFTG), 51 km from the middle of the area, began a volume at 20:28 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.

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

907 
WUUS55 KBOU 192024
SVRBOU
COC013-014-059-192100-
/O.NEW.KBOU.SV.W.0128.210819T2024Z-210819T2100Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Denver CO
224 PM MDT Thu Aug 19 2021

The National Weather Service in Denver Colorado has issued a

* Severe Thunderstorm Warning for...
  Southwestern Broomfield County in northeastern Colorado...
  Northeastern Jefferson County in central Colorado...
  Southeastern Boulder County in northeastern Colorado...

* Until 300 PM MDT.

* At 224 PM MDT, a severe thunderstorm was located over Arvada, or 14
  miles northwest of Denver, moving northeast at 15 mph.

  HAZARD...Golf ball size 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...
  southwestern Broomfield, Superior, Louisville, Westminster and 
  Lafayette.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Large hail and damaging winds and continuous cloud to ground
lightning is occurring with this storm. Move indoors immediately.
Lightning is one of nature's leading killers. Remember, if you can
hear thunder, you are close enough to be struck by lightning.

&&

LAT...LON 4001 10516 3992 10503 3991 10504 3991 10505
      3981 10505 3971 10520 3980 10535
TIME...MOT...LOC 2024Z 210DEG 12KT 3984 10518 

THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

RPK

980 
WWUS55 KBOU 192056 RRA
SVSBOU

Severe Weather Statement
National Weather Service Denver CO
256 PM MDT Thu Aug 19 2021

COC013-014-059-192106-
/O.EXP.KBOU.SV.W.0128.000000T0000Z-210819T2100Z/
Broomfield CO-Jefferson CO-Boulder CO-
256 PM MDT Thu Aug 19 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN BROOMFIELD...
NORTHEASTERN JEFFERSON AND SOUTHEASTERN BOULDER COUNTIES WILL EXPIRE
AT 300 PM MDT...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire.

A Severe Thunderstorm Watch remains in effect until 800 PM MDT for
northeastern Colorado.

LAT...LON 4001 10516 3992 10503 3991 10504 3991 10505
      3981 10505 3971 10520 3980 10535
TIME...MOT...LOC 2056Z 210DEG 12KT 3993 10511 

$$

RPK

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

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.