Alert archive / Colorado / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 149, NWS Denver/Boulder, CO

August 25, 2021Logan County, Morgan County, Weld County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Aug 25, 2021, 11:50 PM MDT for Logan County, Morgan County, Weld County, Colorado. It was in force for 40 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
Aug 25, 2021, 11:50 PM MDT (05:50 UTC)
Expired
Aug 26, 2021, 12:30 AM MDT
In force
40 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Hail
1.25 in
Wind
50.0 mph

Counties Logan County, CO, Morgan County, CO, Weld County, CO

The radar

The Denver radar (KFTG), 114 km from the middle of the area, began a volume at 05:51 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 00:00Z, 5.8 hours before the alert went out and 81 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 00:00Z on 2021-08-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 515 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 00:00Z on 2021-08-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 15 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
515 J/kg
Mixed-layer CIN
-166 J/kg
Mixed-layer LCL
2368 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
15 m²/s²
0-3 km storm-relative helicity
197 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3

Open this sounding in Storm Lab

The text

As transmitted.

555 
WUUS55 KBOU 260550
SVRBOU
COC075-087-123-260630-
/O.NEW.KBOU.SV.W.0149.210826T0550Z-210826T0630Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Denver CO
1150 PM MDT Wed Aug 25 2021

The National Weather Service in Denver Colorado has issued a

* Severe Thunderstorm Warning for...
  Eastern Weld County in northeastern Colorado...
  Northeastern Morgan County in northeastern Colorado...
  Southwestern Logan County in northeastern Colorado...

* Until 1230 AM MDT.

* At 1150 PM MDT, a severe thunderstorm was located 4 miles north of
  Antelope Springs, or 16 miles north of Fort Morgan, moving
  northeast at 20 mph.

  HAZARD...Half dollar size hail.

  SOURCE...Radar indicated.

  IMPACT...Damage to vehicles is expected.

* This severe thunderstorm will be near...
  Stoneham around 1205 AM MDT.

Other locations in the path of this severe thunderstorm include
Willard and Pawnee Pass.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4043 10373 4056 10384 4077 10351 4048 10334
TIME...MOT...LOC 0550Z 243DEG 19KT 4049 10372 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.25 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...<50 MPH

$$

ENTREKIN

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 25, 11:43 PM MDTSpecial Weather StatementBOUMorgan47 min
Aug 26, 12:24 AM MDTSpecial Weather StatementBOUMorgan51 min
Aug 26, 1:45 AM MDTSpecial Weather StatementBOUMorgan45 min
Aug 26, 2:52 PM MDTSevere Thunderstorm WarningBOULincoln38 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.