Mesoscale Discussion 1514

Issued

Aug 13, 2021, 3:26 PM CDT (20:26 UTC)

Expired

Aug 13, 2021, 6:00 PM CDT

In force

3 hr

Issued by

the Storm Prediction Center

Concerning

Severe potential...watch unlikely

Chance of a watch

5%

The Norman radar (KTLX), 42 km from the middle of the area, began a volume at 20:25 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.

684 
ACUS11 KWNS 132026
SWOMCD
SPC MCD 132026 
OKZ000-TXZ000-132300-

Mesoscale Discussion 1514
NWS Storm Prediction Center Norman OK
0326 PM CDT Fri Aug 13 2021

Areas affected...Central Oklahoma

Concerning...Severe potential...Watch unlikely 

Valid 132026Z - 132300Z

Probability of Watch Issuance...5 percent

SUMMARY...Thunderstorms will likely increase in coverage through the
early evening hours as convection develops along remnant outflow
boundaries during peak destabilization. Weak flow aloft will
generally limit the duration and coverage of the severe threat,
though sporadic severe winds will be possible.

DISCUSSION...Thunderstorms have been ongoing through the afternoon
across central OK and far northwest TX thanks to a combination of
weak forcing for ascent along remnant outflow/confluence axes and
parcels reaching their convective temperatures. Widespread dewpoints
in the low 70s are supporting 1000-2000 J/kg MLCAPE across much of
the state with MLCIN eroding as boundary-layer heating/mixing
continues. Thunderstorm coverage will likely increase as new storms
develop along existing and subsequent outflow boundaries within the
unstable air mass. Weak deep-layer flow will limit the severe
weather potential, but steep low-level lapse rates will support a
severe downburst wind potential for locations that have not already
experienced convective overturning (such winds have already been
observed with a collapsing cell in northern OK that produced a 71
mph wind gust at the Perkins, OK Mesonet site). This wind threat
will remain fairly isolated given poor storm organization, and will
quickly diminish near sunset with the onset of boundary-layer
stabilization. Given the sporadic nature of the threat, a watch is
not expected.

..Moore/Hart.. 08/13/2021

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

ATTN...WFO...TSA...OUN...LUB...AMA...

LAT...LON   34630022 35579999 36149942 36639789 36909581 36759500
            35999495 35639537 35379599 34969694 34739773 34449849
            34229996 34630022

Mesoscale Discussions in Oklahoma, 2021Mesoscale Discussions in Texas, 2021Every mesoscale discussion in 2021

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.