Alert archive / Colorado / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 14, NWS Denver/Boulder, CO

May 2, 20214 counties in Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at May 2, 2021, 1:17 PM MDT for 4 counties in Colorado. It was in force for 28 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
May 2, 2021, 1:17 PM MDT (19:17 UTC)
Expired
May 2, 2021, 1:45 PM MDT
In force
28 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Adams County, CO, Logan County, CO, Morgan County, CO, Washington County, CO

The radar

The Denver radar (KFTG), 105 km from the middle of the area, began a volume at 19:21 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
May 2, 11:45 AM MDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 7.3 hours before the alert went out and 42 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.

771 
WUUS55 KBOU 021917
SVRBOU
COC001-075-087-121-021945-
/O.NEW.KBOU.SV.W.0014.210502T1917Z-210502T1945Z/

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

The National Weather Service in Denver Colorado has issued a

* Severe Thunderstorm Warning for...
  Eastern Morgan County in northeastern Colorado...
  Western Washington County in northeastern Colorado...
  Southwestern Logan County in northeastern Colorado...
  Eastern Adams County in northeastern Colorado...

* Until 145 PM MDT.

* At 116 PM MDT, severe thunderstorms were located along a line
  extending from 5 miles north of Antelope Springs to 7 miles north
  of Cottonwood Valley, or along a line extending from 18 miles north
  of Fort Morgan to 33 miles north of Limon, moving east at 25 mph.

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

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees. Hail damage to 
           vehicles is expected.

* Locations impacted include...
  Fort Morgan, Brush, Merino, Hillrose, Gary, Prewitt Reservoir,
  Shamrock, Antelope Springs, Twelve-Mile Corner, Adena School,
  Woodlin School, Lindon, Snyder, Midway, Last Chance, Woodrow and
  Atwood.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4053 10317 3972 10333 3975 10385 4052 10373
TIME...MOT...LOC 1916Z 270DEG 23KT 4051 10371 3974 10382 

HAIL...1.00IN
WIND...60MPH
 
$$

MEIER
1 follow-up statement
340 
WWUS55 KBOU 021939
SVSBOU

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

COC001-075-087-121-021949-
/O.EXP.KBOU.SV.W.0014.000000T0000Z-210502T1945Z/
Morgan CO-Washington CO-Logan CO-Adams CO-
139 PM MDT Sun May 2 2021

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN MORGAN...WESTERN
WASHINGTON...SOUTHWESTERN LOGAN AND EASTERN ADAMS COUNTIES WILL
EXPIRE AT 145 PM MDT...
            
The storms which prompted the warning have weakened below severe
limits, and no longer pose an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However gusty
winds are still possible with these thunderstorms.

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

LAT...LON 4053 10317 3972 10333 3975 10385 4052 10373
TIME...MOT...LOC 1939Z 270DEG 23KT 4051 10354 3974 10365 

$$

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, 11:40 AM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe, Denver50 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.