Alert archive / Wyoming / Special Weather Statements in 2021

Special Weather Statement, NWS Cheyenne, WY

August 15, 2021Albany County, Wyoming

NWS Cheyenne, WY issued this special weather statement at Aug 15, 2021, 2:21 PM MDT for Albany County, Wyoming. It was in force for 24 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 15, 2021, 2:21 PM MDT (20:21 UTC)
Expired: Aug 15, 2021, 2:45 PM MDT
In force: 24 min
Issued by: NWS Cheyenne, WY
Hail: 0.50 in
Wind: 40

County Albany County, WY

The radar

The Cheyenne radar (KCYS), 147 km from the middle of the area, began a volume at 20:22 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

Riverton, WY (KRIW), launched 12:00Z, 8.4 hours before the alert went out and 219 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 2705 m above ground
0-6 km bulk shear: 13 kt
0-1 km storm-relative helicity: -12 m²/s²
0-3 km storm-relative helicity: 46 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

379 
WWUS85 KCYS 152021
SPSCYS

Special Weather Statement
National Weather Service Cheyenne WY
221 PM MDT Sun Aug 15 2021
 
WYZ105-152045-
Shirley Basin WY-
221 PM MDT Sun Aug 15 2021

...A strong thunderstorm will impact portions of east central Carbon
and northwestern Albany Counties through 245 PM MDT...

At 221 PM MDT, Doppler radar was tracking a strong thunderstorm near
Medicine Bow, or 55 miles northwest of Laramie, moving southeast at 5
mph.

HAZARD...Winds in excess of 40 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.

This storm will remain over mainly rural areas of east central Carbon
and northwestern Albany Counties.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building. 

&&

LAT...LON 4201 10625 4205 10614 4197 10604 4191 10613
      4193 10627
TIME...MOT...LOC 2021Z 295DEG 5KT 4199 10616 

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

$$

Mokry

The office that day

Everything else NWS Cheyenne, WY issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 14, 7:01 PM MDT	Severe Thunderstorm Warning	CYS	Laramie	44 min
Aug 14, 7:12 PM MDT	Severe Thunderstorm Warning Considerable damage threat	CYS	Laramie	48 min
Aug 14, 7:36 PM MDT	Severe Thunderstorm Warning	CYS	Laramie	39 min
Aug 15, 12:42 PM MDT	Areal Flood Advisory	CYS	Albany, Carbon	3 hr
Aug 15, 1:03 PM MDT	Special Weather Statement	CYS	Platte	42 min
Aug 15, 1:06 PM MDT	Areal Flood Advisory	CYS	Albany	3 hr
Aug 15, 1:42 PM MDT	Areal Flood Advisory	CYS	Albany, Carbon, Converse	2 hr
Aug 15, 2:10 PM MDT	Special Weather Statement	CYS	Albany	35 min
Aug 15, 3:47 PM MDT	Special Weather Statement	CYS	Albany	28 min
Aug 15, 3:49 PM MDT	Special Weather Statement	CYS	Albany	26 min
Aug 15, 4:25 PM MDT	Special Weather Statement	CYS	Albany	50 min
Aug 15, 4:46 PM MDT	Flash Flood Warning Considerable damage threat	CYS	Albany	95 min
Aug 14, 6:21 PM MDT	Severe Thunderstorm Warning Considerable damage threat	CYS	Box Butte, Morrill	39 min
Aug 14, 6:29 PM MDT	Severe Thunderstorm Warning	CYS	Dawes	46 min
Aug 14, 7:09 PM MDT	Severe Thunderstorm Warning	CYS	Dawes	34 min
Aug 14, 7:34 PM MDT	Severe Thunderstorm Warning Considerable damage threat	CYS	Cheyenne, Kimball, Morrill	41 min

Nearby

Special Weather Statements in Wyoming, 2021 Every 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.