Alert archive / Colorado / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 54, NWS Denver/Boulder, CO

May 29, 2021Weld County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at May 29, 2021, 2:29 PM MDT for Weld County, Colorado. It was in force for 31 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 29, 2021, 2:29 PM MDT (20:29 UTC)
Expired
May 29, 2021, 3:00 PM MDT
In force
31 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Hail
1.25 in
Wind
50.0 mph

County Weld County, CO

The radar

The Cheyenne radar (KCYS), 26 km from the middle of the area, began a volume at 20:33 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 nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 8.5 hours before the alert went out and 173 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 2021-05-29Temperature 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 2021-05-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -78 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
2325 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
-78 m²/s²
0-3 km storm-relative helicity
92 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

076 
WUUS55 KBOU 292029
SVRBOU
COC123-292100-
/O.NEW.KBOU.SV.W.0054.210529T2029Z-210529T2100Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Denver CO
229 PM MDT Sat May 29 2021

The National Weather Service in Denver Colorado has issued a

* Severe Thunderstorm Warning for...
  Northwestern Weld County in northeastern Colorado...

* Until 300 PM MDT.

* At 229 PM MDT, a severe thunderstorm was located 5 miles northeast 
  of Natural Fort, or 9 miles southwest of Cheyenne, moving east-
  southeast at 20 mph.

  HAZARD...Half dollar size hail.

  SOURCE...Radar indicated.

  IMPACT...Damage to vehicles is expected.

* Locations impacted include...
  Rockport and Natural Fort. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4084 10462 4092 10493 4100 10494 4100 10456
TIME...MOT...LOC 2029Z 290DEG 18KT 4102 10487 

HAIL...1.25IN
WIND...<50MPH
 
$$

SCHLATTER
1 follow-up statement
401 
WWUS55 KBOU 292042
SVSBOU

Severe Weather Statement
National Weather Service Denver CO
242 PM MDT Sat May 29 2021

COC123-292100-
/O.CON.KBOU.SV.W.0054.000000T0000Z-210529T2100Z/
Weld CO-
242 PM MDT Sat May 29 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM MDT
FOR NORTHERN WELD COUNTY...

At 242 PM MDT, a severe thunderstorm was located 5 miles northeast of
Natural Fort, or 10 miles south of Cheyenne, moving southeast at 20
mph.

HAZARD...Quarter size hail.

SOURCE...Radar indicated.

IMPACT...Damage to vehicles is expected.

Locations impacted include...
Rockport.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4099 10457 4084 10462 4092 10490 4099 10491
TIME...MOT...LOC 2042Z 295DEG 16KT 4099 10482 

HAIL...1.00IN
WIND...<50MPH
 
$$

SCHLATTER

The office that day

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

IssuedProductOfficeCountiesLasted
May 29, 6:20 AM MDTDense Fog AdvisoryBOUElbert, Lincoln, Washington, Weld100 min
May 29, 1:34 PM MDTSpecial Weather StatementBOUBoulder26 min
May 29, 1:55 PM MDTSevere Thunderstorm WarningBOUElbert35 min
May 29, 2:07 PM MDTSevere Thunderstorm WarningBOUDouglas23 min
May 29, 2:59 PM MDTSpecial Weather StatementBOUWeld31 min
May 29, 3:39 PM MDTAreal Flood AdvisoryBOULarimer83 min
May 29, 4:58 PM MDTSevere Thunderstorm WarningBOULincoln32 min
May 29, 5:16 PM MDTSevere Thunderstorm WarningBOULincoln29 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.