Alert archive / Colorado / Mesoscale Discussions in 2021
Mesoscale Discussion 562
The Storm Prediction Center issued this mesoscale discussion at May 8, 2021, 2:59 PM MDT for 14 counties in Colorado. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- May 8, 2021, 2:59 PM MDT (20:59 UTC)
- Expired
- May 8, 2021, 5:00 PM MDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch unlikely
- Chance of a watch
- 20%
Counties Adams County, CO, Arapahoe County, CO, Bent County, CO, Cheyenne County, CO, Crowley County, CO, Denver County, CO, Douglas County, CO, El Paso County, CO, Elbert County, CO, Kiowa County, CO, Lincoln County, CO, Morgan County, CO, Prowers County, CO, Washington County, CO
The radar
The Pueblo radar (KPUX), 76 km from the middle of the area, began a volume at 20:59 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 (KDNR), launched 12:00Z, 9.0 hours before the alert went out and 111 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 3524 m above ground
- 0-6 km bulk shear
- 43 kt
- 0-1 km storm-relative helicity
- 60 m²/s²
- 0-3 km storm-relative helicity
- 46 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
892
ACUS11 KWNS 082059
SWOMCD
SPC MCD 082059
KSZ000-COZ000-082300-
Mesoscale Discussion 0562
NWS Storm Prediction Center Norman OK
0359 PM CDT Sat May 08 2021
Areas affected...Eastern Colorado
Concerning...Severe potential...Watch unlikely
Valid 082059Z - 082300Z
Probability of Watch Issuance...20 percent
SUMMARY...Developing thunderstorms may produce sporadic damaging
winds across eastern Colorado through the early evening hours. This
threat should remain isolated, and a watch is not expected.
DISCUSSION...Recent radar and GOES IR trends from the Denver, CO
region show an uptick in convection over the past 30 minutes as a
passing cold front induces an upslope flow regime over the CO front
range. Despite the cold frontal passage, the air mass over the CO
Plains remains supportive for convection thanks to cold temperatures
aloft and nearly 9 C/km mid-level lapse rates that are allowing for
around 500 J/kg SBCAPE. Nearly 40 F dewpoint depressions across the
region are indicative of a dry, well-mixed boundary layer, and this
idea is supported by recent RAP forecast soundings. This low-level
thermodynamic profile is supportive of strong downdrafts, and 40-50
knots of effective bulk shear may support some cold pool
organization and a damaging wind threat with any larger clusters.
Convective coverage is somewhat uncertain since the primary forcing
mechanism will likely remain confined along the front range in the
upslope flow regime. Furthermore, the instability is not expected to
substantially improve given gradual cold advection and patchy cloud
cover, and a few discrete cells have recently shown only transient
intensification. The limited nature of this threat precludes the
need for a watch.
..Moore/Thompson.. 05/08/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...DDC...GLD...PUB...BOU...
LAT...LON 38020396 38480451 38850488 39500502 40280494 40610425
40470349 39660295 39190250 38500199 37780202 37640218
37620264 38020396Nearby
Mesoscale Discussions in Colorado, 2021Every mesoscale discussion in 2021
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.