Alert archive / Colorado / Mesoscale Discussions in 2020
Mesoscale Discussion 1303
The Storm Prediction Center issued this mesoscale discussion at Jul 21, 2020, 1:12 PM MDT for 22 counties in Colorado; 6 counties in Nebraska; 5 counties in Wyoming. It was in force for 93 min.
The area
The outline as issued.
The facts
- Issued
- Jul 21, 2020, 1:12 PM MDT (19:12 UTC)
- Expired
- Jul 21, 2020, 2:45 PM MDT
- In force
- 93 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...severe thunderstorm watch likely
- Chance of a watch
- 95%
All 33 counties
Adams County, CO, Arapahoe County, CO, Bent County, CO, Broomfield County, CO, Cheyenne County, CO, Crowley County, CO, Denver County, CO, Douglas County, CO, El Paso County, CO, Elbert County, CO, Jefferson County, CO, Kiowa County, CO, Kit Carson County, CO, Las Animas County, CO, Lincoln County, CO, Logan County, CO, Morgan County, CO, Otero County, CO, Pueblo County, CO, Washington County, CO, Weld County, CO, Yuma County, CO, Banner County, NE, Cheyenne County, NE, Kimball County, NE, Morrill County, NE, Scotts Bluff County, NE, Sioux County, NE, Converse County, WY, Goshen County, WY, Laramie County, WY, Niobrara County, WY, Platte County, WY
The radar
The Cheyenne radar (KCYS), 81 km from the middle of the area, began a volume at 19:15 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 watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Denver, CO (KDNR), launched 12:00Z, 7.2 hours before the alert went out and 114 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.
- Mixed-layer CAPE
- 686 J/kg
- Mixed-layer CIN
- -192 J/kg
- Mixed-layer LCL
- 1080 m above ground
- 0-6 km bulk shear
- 14 kt
- 0-1 km storm-relative helicity
- -10 m²/s²
- 0-3 km storm-relative helicity
- 112 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 21, 1:33 PM MDT | Severe Thunderstorm Watch | SPC | Adams, Arapahoe, Boulder, Broomfield, Crowley, Denver and 14 more | 7 hr |
| Jul 21, 5:22 PM MDT | Mesoscale Discussion | SPC | Adams, Arapahoe, Broomfield, Crowley, Denver, Elbert and 7 more | 113 min |
| Jul 20, 6:17 PM MDT | Mesoscale Discussion | SPC | Arthur, Cherry, Frontier, Garden, Grant, Hayes and 9 more | 88 min |
| Jul 20, 7:00 PM MDT | Severe Thunderstorm Watch | SPC | Dundy, Furnas, Gosper, Harlan, Hitchcock, Red Willow | 5 hr |
| Jul 20, 8:18 PM MDT | Mesoscale Discussion | SPC | Arthur, Blaine, Brown, Chase, Custer, Dawson and 19 more | 87 min |
| Jul 20, 10:29 PM MDT | Mesoscale Discussion | SPC | Buffalo, Franklin, Furnas, Harlan, Howard, Kearney and 3 more | 91 min |
Nearby
Mesoscale Discussions in Colorado, 2020Mesoscale Discussions in Nebraska, 2020Mesoscale Discussions in Wyoming, 2020Every mesoscale discussion in 2020
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.