Alert archive / Colorado / Special Weather Statements in 2021

Special Weather Statement, NWS Denver/Boulder, CO

August 14, 2021Weld County, Colorado

NWS Denver/Boulder, CO issued this special weather statement at Aug 14, 2021, 9:31 PM MDT for Weld County, Colorado. It was in force for 44 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 14, 2021, 9:31 PM MDT (03:31 UTC)
Expired
Aug 14, 2021, 10:15 PM MDT
In force
44 min
Issued by
NWS Denver/Boulder, CO
Hail
0.50 in
Wind
50

County Weld County, CO

The radar

The Denver radar (KFTG), 63 km from the middle of the area, began a volume at 03:35 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, 3.5 hours before the alert went out and 122 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 2021-08-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 666 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 2021-08-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -22 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
666 J/kg
Mixed-layer CIN
-45 J/kg
Mixed-layer LCL
3335 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
-22 m²/s²
0-3 km storm-relative helicity
81 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.4

Open this sounding in Storm Lab

The text

As transmitted.

307 
WWUS85 KBOU 150331
SPSBOU

Special Weather Statement
National Weather Service Denver CO
931 PM MDT Sat Aug 14 2021
 
COZ043-150415-
Central and South Weld County CO-
931 PM MDT Sat Aug 14 2021

...A strong thunderstorm will impact portions of south central Weld
County through 1015 PM MDT...

At 930 PM MDT, Doppler radar was tracking a strong thunderstorm over
Gill, or 10 miles east of Greeley, moving south at 25 mph.

HAZARD...Wind gusts up to 50 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around 
         unsecured objects. Minor damage to outdoor objects is 
         possible.

Locations impacted include...
Kersey, Gill, Barnesville and Roggen. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building. 

&&

LAT...LON 4050 10465 4052 10445 4014 10427 4012 10459
TIME...MOT...LOC 0330Z 346DEG 22KT 4046 10456 

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...50 MPH

$$

GIMMESTAD

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 14, 6:48 PM MDTFlash Flood WarningBOULarimer115 min
Aug 14, 7:15 PM MDTSpecial Weather StatementBOUSummit30 min
Aug 14, 7:38 PM MDTSevere Thunderstorm Warning Considerable damage threatBOUWeld52 min
Aug 14, 8:01 PM MDTSevere Thunderstorm Warning Considerable damage threatBOULogan44 min
Aug 14, 8:28 PM MDTSevere Thunderstorm WarningBOUWeld47 min
Aug 14, 8:29 PM MDTSevere Thunderstorm WarningBOUSedgwick46 min
Aug 14, 8:43 PM MDTSevere Thunderstorm Warning Considerable damage threatBOULogan, Washington47 min
Aug 14, 9:15 PM MDTSevere Thunderstorm WarningBOUPhillips, Sedgwick14 min
Aug 14, 9:28 PM MDTSevere Thunderstorm WarningBOULogan, Washington47 min
Aug 15, 2:32 PM MDTAreal Flood AdvisoryBOUGrand88 min
Aug 15, 5:19 PM MDTSpecial Weather StatementBOULincoln41 min
Aug 15, 5:25 PM MDTSpecial Weather StatementBOUTeller65 min

Nearby

Special Weather Statements in Colorado, 2021Every special weather statement 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.