Mesoscale Discussion 721

Issued

May 21, 2019, 7:26 AM CDT (12:26 UTC)

Expired

May 21, 2019, 9:00 AM CDT

In force

94 min

Issued by

the Storm Prediction Center

The Western Arkansas radar (KSRX), 75 km from the middle of the area, began a volume at 12:26 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.

958 
ACUS11 KWNS 211226
SWOMCD
SPC MCD 211226 
ARZ000-TXZ000-MOZ000-OKZ000-211400-

Mesoscale Discussion 0721
NWS Storm Prediction Center Norman OK
0726 AM CDT Tue May 21 2019

Areas affected...eastern OK into far nothwest AR

Concerning...Tornado Watch 205...

Valid 211226Z - 211400Z

The severe weather threat for Tornado Watch 205 continues.

SUMMARY...A line of bowing segments stretches north to south across
eastern OK early this morning, posing a threat for locally damaging
winds and a few tornadoes. This threat will continue in the
short-term across northeast OK and may persist through the morning
hours further south across east-central and southeast OK into far
western AR.

DISCUSSION...A bowing segment just east/northeast of Tulsa will
continue to shift east/northeast across northeast OK this morning.
The bow should be lifting north of the outflow boundary from prior
convection into a cooler and more stable airmass. As this occurs,
the threat for mesovortex tornadoes should diminish as the
convection becomes more elevated and/or weakens as it outpaces any
recovery/northward shift of the outflow boundary. 

Further south along the line, locally damaging gusts and mesovortex
tornadoes will continue to be possible as this segment of the line
encounters a better quality airmass untouched by prior convection.
Tornadoes have also been reported early this morning with this
southern portions of the line in Marshall County OK. While
instability is weak downstream (500-1000 J/kg MUCAPE), strong
deep-layer shear and large, curved hodographs, as noted in latest
VWP data from Fort Smith AR 88-D, should continue to support
damaging wind and tornado threat into east-central/southeast OK and
possibly far northwest AR. trends will be monitored for possible
watch issuance across northeast TX into west-central AR this
morning.

..Leitman.. 05/21/2019

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...LZK...SGF...SHV...TSA...FWD...OUN...

LAT...LON   36929578 36989545 36939488 36669446 36339421 35929409
            35459404 34769395 33909407 33419431 33479602 33599635
            34739649 35959625 36779602 36929578

Mesoscale Discussions in Oklahoma, 2019Mesoscale Discussions in Arkansas, 2019Mesoscale Discussions in Texas, 2019Every mesoscale discussion in 2019

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.