Alert archive / Colorado / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 13, NWS Denver/Boulder, CO

May 2, 2021Adams County, Arapahoe County, Denver County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at May 2, 2021, 11:40 AM MDT for Adams County, Arapahoe County, Denver County, Colorado. It was in force for 50 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
May 2, 2021, 11:40 AM MDT (17:40 UTC)
Expired
May 2, 2021, 12:30 PM MDT
In force
50 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Hail
0.88 in
Wind
60.0 mph

Counties Adams County, CO, Arapahoe County, CO, Denver County, CO

The radar

The Denver radar (KFTG), 14 km from the middle of the area, began a volume at 17:43 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
May 2, 11:47 AM MDTTSTM WND GST 62Denver Intl Airport, CO
May 2, 11:50 AM MDTTSTM WND DMG2 N Manila Village, COREPORT FROM MPING: 1-INCH TREE LIMBS BROKEN; SHINGLES BLOWN OFF.

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 12:00Z, 5.7 hours before the alert went out and 126 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 2021-05-02Temperature 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 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 12:00Z on 2021-05-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -89 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
1976 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
-89 m²/s²
0-3 km storm-relative helicity
10 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

812 
WUUS55 KBOU 021740
SVRBOU
COC001-005-031-021830-
/O.NEW.KBOU.SV.W.0013.210502T1740Z-210502T1830Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Denver CO
1140 AM MDT Sun May 2 2021

The National Weather Service in Denver Colorado has issued a

* Severe Thunderstorm Warning for...
  Western Arapahoe County in northeastern Colorado...
  Northeastern Denver County in northeastern Colorado...
  Western Adams County in northeastern Colorado...

* Until 1230 PM MDT.

* At 1140 AM MDT, a severe thunderstorm was located 4 miles southwest
  of Barr Lake, or 14 miles north of Denver, moving east at 25 mph.

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

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Northeastern Denver, Aurora, eastern Thornton, Commerce City,
  Brighton, Denver International Airport, D.I.A Terminal and
  Concourses, Bennett, Manila Village, Buckley AFB, Watkins, Barr
  Lake, Todd Creek and Strasburg.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3976 10498 3999 10490 3999 10425 3957 10443
TIME...MOT...LOC 1740Z 288DEG 23KT 3992 10485 

HAIL...0.88IN
WIND...60MPH
 
$$

MEIER
1 follow-up statement
992 
WWUS55 KBOU 021821
SVSBOU

Severe Weather Statement
National Weather Service Denver CO
1221 PM MDT Sun May 2 2021

COC001-005-031-021830-
/O.EXP.KBOU.SV.W.0013.000000T0000Z-210502T1830Z/
Arapahoe CO-Denver CO-Adams CO-
1221 PM MDT Sun May 2 2021

...THE SEVERE THUNDERSTORM WARNING FOR WESTERN ARAPAHOE...
NORTHEASTERN DENVER AND WESTERN ADAMS COUNTIES WILL EXPIRE AT 1230 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 to 50 mph are still possible.

A Severe Thunderstorm Watch remains in effect until 700 PM MDT for
northeastern Colorado.

LAT...LON 3976 10498 3999 10490 3999 10425 3957 10443
TIME...MOT...LOC 1820Z 288DEG 23KT 3984 10454 

$$

MEIER

The office that day

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

IssuedProductOfficeCountiesLasted
May 1, 7:40 PM MDTSpecial Weather StatementBOUBroomfield35 min
May 2, 3:42 AM MDTWinter Storm WarningBOUBoulder, Clear Creek, Gilpin, Grand, Jackson, Jefferson and 3 more34 hr
May 2, 10:36 AM MDTSpecial Weather StatementBOUBoulder24 min
May 2, 11:01 AM MDTSpecial Weather StatementBOUBroomfield29 min
May 2, 1:17 PM MDTSevere Thunderstorm WarningBOUAdams, Logan, Morgan, Washington28 min
May 2, 2:13 PM MDTSevere Thunderstorm WarningBOULincoln32 min
May 2, 2:19 PM MDTWinter Weather AdvisoryBOUBoulder, Clear Creek, Douglas, Gilpin, Grand, Jackson and 3 more23 hr
May 2, 4:07 PM MDTFlash Flood WarningBOULarimer3 hr
May 2, 5:04 PM MDTSpecial Weather StatementBOUWeld41 min
May 2, 5:47 PM MDTAreal Flood AdvisoryBOUBoulder88 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.