NWS Storm Prediction Center Norman OK
1208 PM CDT Wed May 27 2020
Areas affected...Parts of central into southeast Texas
Concerning...Severe potential...Watch possible
Valid 271708Z - 271915Z
Probability of Watch Issuance...40 percent
SUMMARY...The initiation of severe thunderstorm development has
seemed more probable later this afternoon near or north of the
Edwards Plateau vicinity. However, further increase and
intensification of thunderstorms now south of the Dallas-Forth Worth
Metroplex seems probable, and could be accompanied by increasing
risk for severe hail and wind to the west of the Interstate 45
corridor through 19-21Z. Trends are being monitored for the
possibility of a severe weather watch.
DISCUSSION...Recent thunderstorm development to the south of the
Dallas-Fort Worth metroplex probably has been aided by an initial
area of strengthening mid-level forcing for ascent associated with
an impulse pivoting around the larger-scale south central Plains
mid-level low. This appears to have been supported by relatively
weak CAPE, due to seasonably modest low-level moisture around the
Metroplex. And model output has indicated a greater convective
signal with a forecast increase in forcing for ascent with another
perturbation, roughly around the Abilene/San Angelo/Brownwood areas
during the 19-21Z time frame.
However, southeast of the ongoing storms, heating of a more moist
boundary layer (with mid/upper 60s F surface dew points) is already
well underway, with mixed-layer CAPE likely to continue to increase
in excess of 2000 J/kg through early to mid afternoon. Increasing
southeasterly inflow of this air, beneath 30-40+ kt northwesterly
500 mb flow, probably will support substantive further updraft
intensification, and upscale convective growth over the next few
hours. This may be accompanied by increasing risk for severe hail,
and favorable shear could contribute to the evolution of an
increasingly organized convective system with potential for
producing strong wind gusts, near/west of the Interstate-45
corridor.
..Kerr/Hart.. 05/27/2020
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...HGX...FWD...EWX...SJT...
