Alert archive / Colorado / Mesoscale Discussions in 2018
Mesoscale Discussion 962
The Storm Prediction Center issued this mesoscale discussion at Jun 30, 2018, 4:40 PM MDT for 15 counties in Colorado; 4 counties in Kansas; 7 counties in Nebraska. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Jun 30, 2018, 4:40 PM MDT (22:40 UTC)
- Expired
- Jun 30, 2018, 6:45 PM MDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
All 26 counties
Adams County, CO, Arapahoe County, CO, Denver County, CO, Douglas County, CO, El Paso County, CO, Elbert County, CO, Kit Carson County, CO, Lincoln County, CO, Logan County, CO, Morgan County, CO, Phillips County, CO, Sedgwick County, CO, Washington County, CO, Weld County, CO, Yuma County, CO, Cheyenne County, KS, Rawlins County, KS, Sherman County, KS, Thomas County, KS, Banner County, NE, Box Butte County, NE, Cheyenne County, NE, Deuel County, NE, Kimball County, NE, Morrill County, NE, Scotts Bluff County, NE
The radar
The Goodland radar (KGLD), 131 km from the middle of the area, began a volume at 22:40 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 (KDEN), launched 12:00Z, 10.7 hours before the alert went out and 39 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
- 189 J/kg
- Mixed-layer CIN
- -224 J/kg
- Mixed-layer LCL
- 806 m above ground
- 0-6 km bulk shear
- 32 kt
- 0-1 km storm-relative helicity
- -36 m²/s²
- 0-3 km storm-relative helicity
- -44 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.7
The text
As transmitted.
634
ACUS11 KWNS 302240
SWOMCD
SPC MCD 302240
KSZ000-NEZ000-COZ000-WYZ000-010045-
Mesoscale Discussion 0962
NWS Storm Prediction Center Norman OK
0540 PM CDT Sat Jun 30 2018
Areas affected...Northeast into east-central Colorado...Nebraska
Panhandle...far northwest Kansas
Concerning...Severe Thunderstorm Watch 246...
Valid 302240Z - 010045Z
The severe weather threat for Severe Thunderstorm Watch 246
continues.
SUMMARY...Isolated severe threat continues across Severe
Thunderstorm Watch 0246, with a WW issuance possible farther to the
southeast. Large hail and isolated damaging wind gusts will be the
main threats.
DISCUSSION...Isolated storms are ongoing from the Nebraska Panhandle
to central Colorado, just east of the Rocky Mountains. As a 500 mb
vort-max across south central Wyoming continues to move eastward,
large scale lift may assist in initiating additional storms across
Severe Thunderstorm Watch 0246 and perhaps points east (as indicated
by recent CAM guidance).
While buoyancy is rather modest immediately along the Colorado
Front-range, 1500-2000 J/kg MLCAPE (driven by 7.5+ C/km mid-level
lapse rates and 60+ F dewpoints) and 50+ knot effective bulk shear
is present from far northeast Colorado into southwest Nebraska and
northwest Kansas. This suggests favorable conditions for organized
updrafts capable of at least isolated large hail and damaging wind
gusts are in place. Multiple surface boundaries are present just to
the southeast of Severe Thunderstorm Watch 0246 and storms may
initiate along these boundaries in the next few hours. As such,
convective trends will be monitored for potential eastward issuance
of a new WW.
..Squitieri/Gleason/Thompson.. 06/30/2018
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LBF...GLD...PUB...BOU...CYS...
LAT...LON 38690472 38940503 39620498 40410487 40980457 41780392
42220347 42320275 41790235 41320229 40850233 40500222
40010174 39980163 39870084 39630048 39170072 39120130
39020205 38890275 38620388 38690472SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 30, 1:03 PM MDT | Mesoscale Discussion | SPC | Adams, Broomfield, Larimer, Logan, Morgan, Phillips and 3 more | 87 min |
| Jun 30, 2:03 PM MDT | Severe Thunderstorm Watch | SPC | Adams, Arapahoe, Douglas, Elbert, El Paso, Lincoln and 6 more | 7 hr |
| Jun 30, 5:09 PM MDT | Severe Thunderstorm Watch | SPC | Cheyenne, Kit Carson, Yuma | 7 hr |
| Jun 29, 8:37 PM MDT | Mesoscale Discussion | SPC | Decatur, Ellis, Finney, Gove, Graham, Lane and 12 more | 113 min |
| Jun 30, 2:15 PM MDT | Mesoscale Discussion | SPC | Allen, Anderson, Bourbon, Butler, Chase, Chautauqua and 18 more | 90 min |
| Jun 30, 2:50 PM MDT | Severe Thunderstorm Watch | SPC | Butler, Chase, Chautauqua, Cowley, Elk, Greenwood and 7 more | 5 hr |
| Jun 30, 3:40 PM MDT | Mesoscale Discussion | SPC | Atchison, Brown, Chase, Clay, Coffey, Doniphan and 19 more | 95 min |
| Jun 30, 3:57 PM MDT | Severe Thunderstorm Watch | SPC | Anderson, Atchison, Brown, Clay, Coffey, Dickinson and 20 more | 6 hr |
| Jun 30, 5:15 PM MDT | Mesoscale Discussion | SPC | Butler, Chautauqua, Cowley, Elk, Greenwood, Harper and 8 more | 90 min |
| Jun 30, 12:35 AM MDT | Mesoscale Discussion | SPC | Antelope, Arthur, Banner, Blaine, Brown, Garden and 12 more | 85 min |
| Jun 30, 11:40 AM MDT | Mesoscale Discussion | SPC | Boone, Burt, Butler, Clay, Colfax, Cuming and 19 more | 3 hr |
| Jun 30, 12:39 PM MDT | Severe Thunderstorm Watch | SPC | Burt, Butler, Cass, Dodge, Douglas, Gage and 12 more | 7 hr |
| Jun 30, 2:11 PM MDT | Mesoscale Discussion | SPC | Adams, Boone, Buffalo, Chase, Clay, Custer and 29 more | 94 min |
| Jun 30, 2:26 PM MDT | Severe Thunderstorm Watch | SPC | Adams, Arthur, Blaine, Buffalo, Chase, Cherry and 39 more | 8 hr |
| Jun 30, 2:40 PM MDT | Mesoscale Discussion | SPC | Cass, Dodge, Douglas, Lancaster, Otoe, Sarpy and 3 more | 2 hr |
| Jun 30, 5:09 PM MDT | Mesoscale Discussion | SPC | Adams, Arthur, Blaine, Buffalo, Butler, Cass and 46 more | 96 min |
Nearby
Mesoscale Discussions in Colorado, 2018Mesoscale Discussions in Nebraska, 2018Mesoscale Discussions in Kansas, 2018Every 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.