Alert archive / Colorado / Mesoscale Discussions in 2018

Mesoscale Discussion 305

May 1, 201812 counties in Colorado; Cheyenne County, Kimball County, Nebraska; Laramie County, Wyoming

The Storm Prediction Center issued this mesoscale discussion at May 1, 2018, 1:01 PM MDT for 12 counties in Colorado; Cheyenne County, Kimball County, Nebraska; Laramie County, Wyoming. It was in force for 119 min.

The area

The outline as issued.

The facts

Issued: May 1, 2018, 1:01 PM MDT (19:01 UTC)
Expired: May 1, 2018, 3:00 PM MDT
In force: 119 min
Issued by: the Storm Prediction Center
Chance of a watch: 5%

Counties Adams County, CO, Arapahoe County, CO, Boulder County, CO, Broomfield County, CO, Denver County, CO, Douglas County, CO, Elbert County, CO, Larimer County, CO, Logan County, CO, Morgan County, CO, Washington County, CO, Weld County, CO, Cheyenne County, NE, Kimball County, NE, Laramie County, WY

The radar

The Cheyenne radar (KCYS), 69 km from the middle of the area, began a volume at 19:03 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 (KDEN), launched 12:00Z, 7.0 hours before the alert went out and 128 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: 42 J/kg
Mixed-layer CIN: -61 J/kg
Mixed-layer LCL: 725 m above ground
0-6 km bulk shear: 52 kt
0-1 km storm-relative helicity: 45 m²/s²
0-3 km storm-relative helicity: 208 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 30, 7:13 PM MDT	Mesoscale Discussion	SPC	Antelope, Boone, Cedar, Custer, Garfield, Greeley and 10 more	92 min
May 1, 12:10 PM MDT	Mesoscale Discussion	SPC	Butler, Cass, Clay, Douglas, Fillmore, Gage and 13 more	3 hr
May 1, 1:47 PM MDT	Tornado Watch	SPC	Adams, Burt, Butler, Cass, Clay, Colfax and 29 more	9 hr
May 1, 4:00 PM MDT	Mesoscale Discussion	SPC	Cass, Clay, Douglas, Fillmore, Gage, Jefferson and 13 more	2 hr

Nearby

Mesoscale Discussions in Colorado, 2018 Mesoscale Discussions in Nebraska, 2018 Mesoscale Discussions in Wyoming, 2018 Every mesoscale discussion in 2018

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.