Alert archive / Wyoming / Mesoscale Discussions in 2004

Mesoscale Discussion 781

May 20, 200410 counties in Wyoming

The Storm Prediction Center issued this mesoscale discussion at May 20, 2004, 4:34 PM MDT for 10 counties in Wyoming. It was in force for 116 min.

The area

The outline as issued.

The facts

Issued
May 20, 2004, 4:34 PM MDT (22:34 UTC)
Expired
May 20, 2004, 6:30 PM MDT
In force
116 min
Issued by
the Storm Prediction Center

Counties Campbell County, WY, Converse County, WY, Crook County, WY, Fremont County, WY, Hot Springs County, WY, Johnson County, WY, Natrona County, WY, Niobrara County, WY, Washakie County, WY, Weston County, WY

The radar

The Riverton/Lander radar (KRIW), 163 km from the middle of the area, began a volume at 22:38 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, 10.6 hours before the alert went out and 157 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, Riverton, WY at 12:00Z on 2004-05-20Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Riverton, WY at 12:00Z on 2004-05-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 31 square meters per square second.1939587897Sfc1 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
933 m above ground
0-6 km bulk shear
61 kt
0-1 km storm-relative helicity
31 m²/s²
0-3 km storm-relative helicity
112 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 20, 4:02 PM MDTMesoscale DiscussionSPCGoshen, Laramie, Platte118 min

Nearby

Mesoscale Discussions in Wyoming, 2004Every mesoscale discussion in 2004

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.