Alert archive / Oklahoma / Mesoscale Discussions in 2021
Mesoscale Discussion 1850
The Storm Prediction Center issued this mesoscale discussion at Oct 13, 2021, 3:26 AM CDT for 6 counties in Kansas; 12 counties in Oklahoma. It was in force for 94 min.
The area
The outline as issued.
The facts
- Issued
- Oct 13, 2021, 3:26 AM CDT (08:26 UTC)
- Expired
- Oct 13, 2021, 5:00 AM CDT
- In force
- 94 min
- Issued by
- the Storm Prediction Center
- Concerning
- Tornado watch 524...526
Counties Butler County, KS, Chase County, KS, Cowley County, KS, Marion County, KS, Sedgwick County, KS, Sumner County, KS, Blaine County, OK, Caddo County, OK, Canadian County, OK, Garfield County, OK, Grant County, OK, Jackson County, OK, Kay County, OK, Kingfisher County, OK, Kiowa County, OK, Logan County, OK, Noble County, OK, Washita County, OK
The radar
The Vance AFB radar (KVNX), 71 km from the middle of the area, began a volume at 08:29 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
Norman, OK (KOUN), launched 00:00Z, 8.4 hours before the alert went out and 122 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
- 496 J/kg
- Mixed-layer CIN
- -164 J/kg
- Mixed-layer LCL
- 662 m above ground
- 0-6 km bulk shear
- 58 kt
- 0-1 km storm-relative helicity
- 331 m²/s²
- 0-3 km storm-relative helicity
- 372 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 5.5
The text
As transmitted.
729
ACUS11 KWNS 130827
SWOMCD
SPC MCD 130826
KSZ000-OKZ000-TXZ000-131000-
Mesoscale Discussion 1850
NWS Storm Prediction Center Norman OK
0326 AM CDT Wed Oct 13 2021
Areas affected...Portions of western/northern OK into south-central
and southeastern KS
Concerning...Tornado Watch 524...526...
Valid 130826Z - 131000Z
The severe weather threat for Tornado Watch 524, 526 continues.
SUMMARY...Mainly an isolated strong to severe wind threat continues
with a line of storms moving eastward.
DISCUSSION...Observations from the OK Mesonet and other sites in
OK/KS show that the wind gusts associated with an extensive squall
line have largely remained sub-severe over the past hour or so, with
a wind gust to 50 kt at KICT at 0810Z being the exception. While
there is at least moderate boundary-layer instability ahead of the
line per mesoanalysis, there is likely also a shallow near-surface
stable layer which is inhibiting convective downdraft potential to
some extent. Even so, there is still some chance for occasional
strong to severe wind gusts to breach this stable layer and reach
the surface given the strength of the low/mid-level flow present
across OK/KS. Both low/deep-layer shear vectors are becoming
oriented increasingly parallel to the squall line (see recent VWPs
from KFDR, KVNX, and KICT). This should tend to limit the potential
for low-level circulations embedded within the QLCS, but a brief
tornado still remains possible given the strength of the low-level
flow associated with a strong, 50-60+ kt southerly low-level jet.
..Gleason.. 10/13/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...TSA...ICT...OUN...
LAT...LON 34539985 34999942 35479907 36169857 36889799 37759754
38499703 38439640 37029649 35779719 34939813 34399916
34539985SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 12, 8:56 PM CDT | Mesoscale Discussion | SPC | Barber, Barton, Clark, Edwards, Ellis, Ellsworth and 19 more | 64 min |
| Oct 12, 9:35 PM CDT | Tornado Watch | SPC | Barber, Barton, Butler, Chase, Clark, Comanche and 25 more | 7 hr |
| Oct 12, 10:40 PM CDT | Severe Thunderstorm Watch | SPC | Clay, Cloud, Dickinson, Geary, Jewell, Mitchell and 9 more | 6 hr |
| Oct 12, 11:34 PM CDT | Mesoscale Discussion | SPC | Barber, Barton, Comanche, Edwards, Ellsworth, Harper and 13 more | 86 min |
| Oct 13, 12:54 AM CDT | Mesoscale Discussion | SPC | Clay, Cloud, Jewell, Mitchell, Republic, Washington | 96 min |
| Oct 13, 1:52 AM CDT | Mesoscale Discussion | SPC | Barber, Butler, Chase, Cowley, Harper, Harvey and 7 more | 83 min |
| Oct 13, 2:54 AM CDT | Mesoscale Discussion | SPC | Dickinson, Geary, Marshall, Morris, Pottawatomie, Riley and 2 more | 96 min |
| Oct 13, 5:16 AM CDT | Mesoscale Discussion | SPC | Chautauqua, Elk, Labette, Montgomery, Neosho, Wilson and 1 more | 59 min |
| Oct 13, 7:34 AM CDT | Mesoscale Discussion | SPC | Bourbon, Cherokee, Crawford, Labette, Linn | 116 min |
| Oct 12, 7:30 PM CDT | Mesoscale Discussion | SPC | Beaver, Beckham, Caddo, Comanche, Cotton, Custer and 10 more | 2 hr |
| Oct 12, 9:18 PM CDT | Mesoscale Discussion | SPC | Beaver, Beckham, Blaine, Caddo, Canadian, Comanche and 12 more | 117 min |
| Oct 12, 11:05 PM CDT | Tornado Watch | SPC | Alfalfa, Beaver, Beckham, Blaine, Caddo, Canadian and 19 more | 7 hr |
| Oct 13, 1:18 AM CDT | Mesoscale Discussion | SPC | Alfalfa, Beckham, Blaine, Custer, Dewey, Ellis and 7 more | 87 min |
Nearby
Mesoscale Discussions in Oklahoma, 2021Mesoscale Discussions in Kansas, 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.