Alert archive / Wyoming / Mesoscale Discussions in 2013

Mesoscale Discussion 1889

September 17, 20135 states

The Storm Prediction Center issued this mesoscale discussion at Sep 17, 2013, 6:16 PM MDT for 5 states. It was in force for 89 min.

The area

The outline as issued.

The facts

Issued: Sep 17, 2013, 6:16 PM MDT (00:16 UTC)
Expired: Sep 17, 2013, 7:45 PM MDT
In force: 89 min
Issued by: the Storm Prediction Center

All 30 counties

Moffat County, CO, Routt County, CO, Bannock County, ID, Bear Lake County, ID, Bonneville County, ID, Caribou County, ID, Franklin County, ID, Teton County, ID, Carbon County, MT, Cache County, UT, Daggett County, UT, Duchesne County, UT, Morgan County, UT, Rich County, UT, Summit County, UT, Uintah County, UT, Weber County, UT, Big Horn County, WY, Carbon County, WY, Fremont County, WY, Hot Springs County, WY, Johnson County, WY, Lincoln County, WY, Natrona County, WY, Park County, WY, Sublette County, WY, Sweetwater County, WY, Teton County, WY, Uinta County, WY, Washakie County, WY

The radar

The Riverton/Lander radar (KRIW), 132 km from the middle of the area, began a volume at 00:18 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

Salt Lake City I, UT (KSLC), launched 00:00Z, 0.3 hours before the alert went out and 249 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: 230 J/kg
Mixed-layer CIN: -31 J/kg
Mixed-layer LCL: 3419 m above ground
0-6 km bulk shear: 50 kt
0-1 km storm-relative helicity: 149 m²/s²
0-3 km storm-relative helicity: 180 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.6

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.

Issued	Product	Office	Counties	Lasted
Sep 17, 8:23 PM MDT	Mesoscale Discussion	SPC	Bear Lake	67 min
Sep 17, 6:29 PM MDT	Mesoscale Discussion	SPC	Carter, Custer, Dawson, Fallon, Powder River, Prairie and 3 more	61 min
Sep 18, 1:16 PM MDT	Mesoscale Discussion	SPC	Carter, Fallon, Powder River	89 min

Nearby

Mesoscale Discussions in Wyoming, 2013 Mesoscale Discussions in Utah, 2013 Mesoscale Discussions in Idaho, 2013 Every mesoscale discussion in 2013

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.