Alert archive / Colorado / Special Weather Statements in 2021

Special Weather Statement, NWS Denver/Boulder, CO

August 6, 2021Jackson County, Colorado

NWS Denver/Boulder, CO issued this special weather statement at Aug 6, 2021, 6:24 PM MDT for Jackson County, Colorado. It was in force for 36 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 6, 2021, 6:24 PM MDT (00:24 UTC)
Expired
Aug 6, 2021, 7:00 PM MDT
In force
36 min
Issued by
NWS Denver/Boulder, CO
Hail
0.25 in
Wind
50

County Jackson County, CO

The radar

The Cheyenne radar (KCYS), 101 km from the middle of the area, began a volume at 00:24 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, 0.4 hours before the alert went out and 250 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 2021-08-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 4 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 2021-08-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -32 square meters per square second.19395878Sfc1 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
4 J/kg
Mixed-layer CIN
-256 J/kg
Mixed-layer LCL
3329 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
-32 m²/s²
0-3 km storm-relative helicity
94 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

699 
WWUS85 KBOU 070024
SPSBOU

Special Weather Statement
National Weather Service Denver CO
624 PM MDT Fri Aug 6 2021
 
COZ030-033-035-070100-
Jackson County Below 9000 Feet CO-
Larimer and Boulder Counties Between 6000 and 9000 Feet CO-
South and East Jackson/Larimer/North and Northeast Grand/Northwest
Boulder Counties Above 9000 Feet CO-
624 PM MDT Fri Aug 6 2021

...Strong thunderstorms will impact portions of eastern Jackson and
northwestern Larimer Counties through 700 PM MDT...

At 623 PM MDT, Doppler radar was tracking strong thunderstorms along 
a line extending from 6 miles east of Walden to 3 miles northwest of 
Rand, or along a line extending from 42 miles southwest of Laramie 
to 68 miles east of Craig. Movement was east at 40 mph.

HAZARD...Wind gusts up to 50 mph and pea size 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...
Walden, Rand, Cameron Pass, Four Corners, Brownlee, Gould, Chambers
Lake, Glendevey and Kinikinik.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building. 

&&

LAT...LON 4100 10559 4036 10590 4045 10642 4099 10622
      4100 10576
TIME...MOT...LOC 0023Z 269DEG 43KT 4081 10607 4048 10624 

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...50 MPH

$$

SCHLATTER

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 6, 6:15 PM MDTSpecial Weather StatementBOULogan45 min
Aug 6, 6:53 PM MDTFlash Flood WarningBOULarimer2 hr
Aug 6, 7:36 PM MDTSpecial Weather StatementBOULarimer24 min
Aug 6, 7:58 PM MDTAreal Flood AdvisoryBOULarimer2 hr
Aug 6, 10:06 PM MDTAreal Flood AdvisoryBOULarimer84 min
Aug 7, 1:08 PM MDTSpecial Weather StatementBOULincoln52 min
Aug 7, 1:48 PM MDTSevere Thunderstorm WarningBOUElbert, Lincoln42 min
Aug 7, 2:29 PM MDTSevere Thunderstorm WarningBOULincoln33 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.