MD 2009 CONCERNING SEVERE THUNDERSTORM WATCH 580… FOR SOUTH-CENTRAL OKLAHOMA
Mesoscale Discussion 2009
NWS Storm Prediction Center Norman OK
0307 AM CST Tue Dec 13 2022
Areas affected...south-central Oklahoma
Concerning...Severe Thunderstorm Watch 580...
Valid 130907Z - 131100Z
The severe weather threat for Severe Thunderstorm Watch 580
continues.
SUMMARY...A new watch downstream from WW 580 is not expected at this
time. Locally strong gusts may occur with a line of thunderstorms as
it shifts east through early morning, but overall severe potential
appears limited.
DISCUSSION...Modest instability and moderate vertical shear ahead of
an eastward-advancing cold front are contributing to a
semi-organized line of convection early this morning over southwest
OK/northwest TX within WW 580. A cell with at least transient
supercell characteristics has also been noted on the southern edge
of the line moving into Archer and Wichita Counties in northwest TX.
The airmass downstream from WW 580 across south-central OK (south of
the I-40 corridor) remains rather cool, with surface temperatures in
the 53-59 F range. Surface-based instability will remain limited,
with 08z mesoanalysis indicating SBCINH increasing toward the I-35
corridor. While vertical shear typically would support supercells
and rotating cells within the line, poor low-level thermodynamics
will continue to limit severe potential. Isolated strong gusts will
be possible with more intense convection, but overall severe
potential should decrease with eastward extent over the next couple
of hours across south-central OK.
The exception may be near and just south of the Red River where
temperatures and dewpoints are in the low to mid 60s, resulting in
greater instability and weak CINH. The aforementioned supercell on
the southern end of the convective line is occurring within this
environment and may pose the greatest severe risk in the short term.
Depending on trends, a very small watch could be needed near the
immediate Red River vicinity. However, the overall threat appears
limited by the narrow warm sector. A downstream watch is not
expected at this time, but trends will continue to be monitored.
..Leitman.. 12/13/2022
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...TSA...FWD...OUN...
LAT...LON 35259817 35419803 35559744 35509652 35479638 35179604
34699594 34099606 33589640 33379684 33299745 33339801
33519838 33769845 34459829 35259817
