Mesoscale Discussion 2042

Issued

Dec 17, 2021, 1:30 PM CST (19:30 UTC)

Expired

Dec 17, 2021, 3:30 PM CST

In force

2 hr

Issued by

the Storm Prediction Center

Concerning

Severe potential...watch possible

Chance of a watch

40%

Counties Atoka County, OK, Bryan County, OK, Carter County, OK, Coal County, OK, Haskell County, OK, Jefferson County, OK, Johnston County, OK, Latimer County, OK, Love County, OK, Marshall County, OK, Murray County, OK, Pittsburg County, OK, Pontotoc County, OK, Pushmataha County, OK, Clay County, TX, Cooke County, TX, Montague County, TX

The Norman radar (KTLX), 119 km from the middle of the area, began a volume at 19:30 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.

131 
ACUS11 KWNS 171931
SWOMCD
SPC MCD 171930 
OKZ000-TXZ000-172130-

Mesoscale Discussion 2042
NWS Storm Prediction Center Norman OK
0130 PM CST Fri Dec 17 2021

Areas affected...Southeastern Oklahoma and extreme North Texas

Concerning...Severe potential...Watch possible 

Valid 171930Z - 172130Z

Probability of Watch Issuance...40 percent

SUMMARY...An isolated strong to severe storm or two remains possible
this afternoon into early evening, primarily in southeastern
Oklahoma. Damaging winds and marginally severe hail are the main
threats. A more conditional threat for a tornado exists for mature
storms that interact with a differential heating boundary. A watch
is possible depending on convective trends this afternoon.

DISCUSSION...Weak thunderstorms continue to develop along a diffuse
differential heating zone across southern Oklahoma into northwest
Arkansas. Weak warm advection as well as a subtle shortwave appear
to be driving this activity. Surface temperatures in North Texas
into parts of southeastern Oklahoma have warmed into the low/mid 70s
F with low 60s F dewpoints. Though MLCAPE is analyzed to be
1000-1500 J/kg, lift has been weak enough near the boundary that
activity has struggled to mature thus far. Continued heating and
warm advection could support an isolated strong to severe storm or
two this afternoon. Recent visible satellite trends do show some
increase in the convective character of the cumulus in south-central
Oklahoma. Damaging winds and marginally severe hail are the primary
threats. A brief tornado is also possible should a marginally
organized supercell develop and interact with the differential
heating zones -- KSRX VAD data would suggest this potential. Storm
coverage may eventually increase as the front begins to accelerate
southeastward later this evening; however, that activity is likely
to be undercut by the front itself and its severity is less certain.
A watch is possible this afternoon should confidence in severe storm
coverage increase.

..Wendt/Kerr.. 12/17/2021

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

ATTN...WFO...SHV...TSA...FWD...OUN...

LAT...LON   33989811 34309780 34849656 35469539 35469479 35129466
            34249515 33749660 33519793 33559833 33779837 33989811

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.