Mesoscale Discussion 0058
NWS Storm Prediction Center Norman OK
0242 AM CST Thu Jan 30 2025
Areas affected...south central into north central Texas
Concerning...Severe potential...Watch unlikely
Valid 300842Z - 301145Z
Probability of Watch Issuance...20 percent
SUMMARY...In advance of an evolving line of storms along a cold
front progressing across and east of the I-35 corridor of central
Texas, isolated to widely scattered strong to severe storms may
develop through 4-6 AM CST. These may pose potential for producing
small hail and a localized damaging gust or two. A brief tornado
might not be out of the question.
DISCUSSION...A warm elevated mixed-layer across and northeast of the
San Antonio/Austin area has been suppressing convective development
within a moist boundary-layer which has advected inland as far
northwest as the Interstate 35 corridor of central Texas. Beneath
the steeper mid-level lapse rates, forecast soundings indicate a
deep moist surface-based layer (including surface dew points in the
lower/mid 60s F), though one characterized by weak (generally moist
adiabatic) lapse rates. Still, this is contributing to weak
potential instability, in advance of what the latest Rapid Refresh
indicates will become a strengthening, eastward advancing cold
frontal surge across the Interstate 35 corridor by 10-12Z.
It appears that strengthening low-level convergence and frontal
forcing may contribute to an intensifying band of convection, aided
by lift along and to the cool side (above) of the the surface front.
This may coincide with an intensification of southerly pre-frontal
low-level flow (including to 50+ kt around 850 mb). However, it
appears that the strengthening flow will remain largely confined to
the inflow layer, with forecast soundings indicating generally
modest to weak westerly flow in the convective outflow and/or
post-frontal environment.
Of primary concern, their may be a window of opportunity for
intensifying isolated to widely scattered discrete convective
development, rooted closer to the surface, along the strengthening
southerly 850 mb jet axis, where somewhat enlarged, clockwise curved
low-level hodographs may evolve. This could support supercells with
at least some potential for localized damaging surface gusts, or
perhaps a brief tornado, before being overtaken by the frontal band
of thunderstorms.
..Kerr/Smith.. 01/30/2025
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...SHV...HGX...FWD...EWX...
LAT...LON 30609867 31779769 32669699 32689553 31499616 29539711
29289812 29539878 30609867
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