Alert archive / Oklahoma / Mesoscale Discussions in 2017
Mesoscale Discussion 1513
The Storm Prediction Center issued this mesoscale discussion at Aug 16, 2017, 9:55 PM CDT for Benton County, Arkansas; Barry County, McDonald County, Newton County, Missouri; 30 counties in Oklahoma. It was in force for 95 min.
The area
The outline as issued.
The facts
- Issued
- Aug 16, 2017, 9:55 PM CDT (02:55 UTC)
- Expired
- Aug 16, 2017, 11:30 PM CDT
- In force
- 95 min
- Issued by
- the Storm Prediction Center
All 34 counties
Benton County, AR, Barry County, MO, McDonald County, MO, Newton County, MO, Adair County, OK, Caddo County, OK, Canadian County, OK, Cherokee County, OK, Cleveland County, OK, Comanche County, OK, Cotton County, OK, Creek County, OK, Delaware County, OK, Garvin County, OK, Grady County, OK, Greer County, OK, Hughes County, OK, Kiowa County, OK, Lincoln County, OK, Mayes County, OK, McClain County, OK, McIntosh County, OK, Muskogee County, OK, Okfuskee County, OK, Oklahoma County, OK, Okmulgee County, OK, Ottawa County, OK, Pottawatomie County, OK, Rogers County, OK, Seminole County, OK, Stephens County, OK, Tillman County, OK, Tulsa County, OK, Wagoner County, OK
The radar
The Norman radar (KTLX), 42 km from the middle of the area, began a volume at 02:58 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, 2.9 hours before the alert went out and 57 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
- 2168 J/kg
- Mixed-layer CIN
- -48 J/kg
- Mixed-layer LCL
- 1105 m above ground
- 0-6 km bulk shear
- 31 kt
- 0-1 km storm-relative helicity
- 113 m²/s²
- 0-3 km storm-relative helicity
- 180 m²/s²
- Significant tornado parameter
- 0.9
- Supercell composite
- 9.2
The text
As transmitted.
367
ACUS11 KWNS 170255
SWOMCD
SPC MCD 170255
MOZ000-ARZ000-OKZ000-170430-
Mesoscale Discussion 1513
NWS Storm Prediction Center Norman OK
0955 PM CDT Wed Aug 16 2017
Areas affected...Southwest into northeast OK...Far southwest
MO...Northwest AR
Concerning...Severe Thunderstorm Watch 453...
Valid 170255Z - 170430Z
The severe weather threat for Severe Thunderstorm Watch 453
continues.
SUMMARY...A lingering damaging wind risk continues with the line of
thunderstorms moving into the I-44 corridor, but the severe threat
should diminish with time late tonight.
DISCUSSION...The persistent band of thunderstorms that developed
earlier across KS/OK is moving steadily southeastward this evening,
with the strongest convection noted across portions of southwest
into central OK as of 0245Z. Outflow has advanced several miles
ahead of the primary convection across most of the band, though
stronger cells are noted near boundary inflections to the west and
northeast of the OKC metro. This band earlier produced several
measured severe wind gusts across northern OK, and some
damaging-wind risk will continue for the next 1-2 hours, especially
in areas where convection remains rooted near the composite outflow.
A gradual decreasing trend is expected with time late tonight, as
SBCINH increases and convection moves southeastward into a
less-sheared environment. The extended expiration time of 05Z for WW
453 should be sufficient to cover most of the remaining severe
threat across OK. Convection will also spread further east into
southwest MO and northwest AR with time, but weaker instability in
this area should limit the severe threat.
..Dean.. 08/17/2017
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...SGF...TSA...OUN...
LAT...LON 34859980 35909732 36579589 36929461 37019354 36369351
35939442 35359559 34749688 34429770 34279840 34299878
34529929 34859980SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 16, 7:30 PM CDT | Mesoscale Discussion | SPC | Barton, Bates, Benton, Cass, Cedar, Dade and 13 more | 90 min |
| Aug 17, 4:29 PM CDT | Mesoscale Discussion | SPC | Cimarron, Texas | 91 min |
Nearby
Mesoscale Discussions in Oklahoma, 2017Mesoscale Discussions in Missouri, 2017Mesoscale Discussions in Arkansas, 2017Every mesoscale discussion in 2017
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.