Alert archive / Colorado / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 59, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this severe thunderstorm warning at Jun 5, 2021, 7:04 PM MDT for Douglas County, Colorado. It was in force for 41 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
- Jun 5, 2021, 7:04 PM MDT (01:04 UTC)
- Expired
- Jun 5, 2021, 7:45 PM MDT
- In force
- 41 min
- Issued by
- NWS Denver/Boulder, CO
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 50.0 mph
County Douglas County, CO
The radar
The Denver radar (KFTG), 61 km from the middle of the area, began a volume at 01:08 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
| Time | Report | Where | Remark |
|---|---|---|---|
| Jun 5, 7:10 PM MDT | HAIL 1 | 2 S Castle Rock, CO | |
| Jun 5, 7:18 PM MDT | HAIL 0.75 | 1 Wsw Castle Rock, CO | MOST DIME SIZED OR SMALLER. |
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, 1.1 hours before the alert went out and 156 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.
- Mixed-layer CAPE
- 572 J/kg
- Mixed-layer CIN
- -13 J/kg
- Mixed-layer LCL
- 3368 m above ground
- 0-6 km bulk shear
- 7 kt
- 0-1 km storm-relative helicity
- -29 m²/s²
- 0-3 km storm-relative helicity
- -25 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
573
WUUS55 KBOU 060104
SVRBOU
COC035-060145-
/O.NEW.KBOU.SV.W.0059.210606T0104Z-210606T0145Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Denver CO
704 PM MDT Sat Jun 5 2021
The National Weather Service in Denver Colorado has issued a
* Severe Thunderstorm Warning for...
Central Douglas County in northeastern Colorado...
* Until 745 PM MDT.
* At 704 PM MDT, a severe thunderstorm was located near Castle Rock,
or 26 miles south of Denver, moving northeast at 5 mph.
HAZARD...Quarter size hail.
SOURCE...Radar indicated.
IMPACT...Damage to vehicles is expected.
* Locations impacted include...
Castle Rock and Perry Park.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 3926 10491 3926 10498 3931 10503 3940 10494
3942 10482 3932 10477
TIME...MOT...LOC 0104Z 246DEG 5KT 3934 10489
HAIL...1.00IN
WIND...<50MPH
$$
RJK2 follow-up statements
233
WWUS55 KBOU 060124
SVSBOU
Severe Weather Statement
National Weather Service Denver CO
724 PM MDT Sat Jun 5 2021
COC035-060145-
/O.CON.KBOU.SV.W.0059.000000T0000Z-210606T0145Z/
Douglas CO-
724 PM MDT Sat Jun 5 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 745 PM MDT
FOR EAST CENTRAL DOUGLAS COUNTY...
At 723 PM MDT, a severe thunderstorm was located over southwestern
Castle Rock, or 26 miles south of Denver, moving northeast at 5 mph.
The public reported 1 inch hail 2 miles south of Castle Rock at 7:10
PM MDT.
HAZARD...Quarter size hail.
SOURCE...Public.
IMPACT...Damage to vehicles is expected.
Locations impacted include...
Castle Rock.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 3926 10492 3933 10498 3940 10494 3942 10482
3932 10477
TIME...MOT...LOC 0123Z 246DEG 5KT 3935 10486
HAIL...1.00IN
WIND...<50MPH
$$
RJK344
WWUS55 KBOU 060140
SVSBOU
Severe Weather Statement
National Weather Service Denver CO
740 PM MDT Sat Jun 5 2021
COC035-060149-
/O.EXP.KBOU.SV.W.0059.000000T0000Z-210606T0145Z/
Douglas CO-
740 PM MDT Sat Jun 5 2021
...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL DOUGLAS COUNTY
WILL EXPIRE AT 745 PM MDT...
The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning will
be allowed to expire.
The public reported 1 inch hail 2 miles south of Castle Rock at 7:10
PM MDT.
LAT...LON 3926 10492 3933 10498 3940 10494 3942 10482
3932 10477
TIME...MOT...LOC 0139Z 246DEG 5KT 3936 10484
$$
RJKThe office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 5, 6:59 PM MDT | Special Weather Statement | BOU | Douglas | 46 min |
| Jun 6, 12:30 PM MDT | Areal Flood Advisory | BOU | Larimer | 90 min |
| Jun 6, 4:02 PM MDT | Severe Thunderstorm Warning | BOU | Morgan, Weld | 28 min |
| Jun 6, 4:08 PM MDT | Severe Thunderstorm Warning | BOU | Weld | 37 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.