Mesoscale Discussion 1897
NWS Storm Prediction Center Norman OK
0254 PM CDT Thu Aug 07 2025
Areas affected...parts of western and central North Dakota
Concerning...Severe potential...Watch possible
Valid 071954Z - 072200Z
Probability of Watch Issuance...40 percent
SUMMARY...Uncertainty lingers concerning potential thunderstorm
coverage and sustenance into and through 5-7 PM CDT. However, any
sustained thunderstorm development may include rapidly intensifying
supercells accompanied by a risk for large hail, locally damaging
wind gusts and perhaps a couple of tornadoes.
DISCUSSION...Along and southeast of a weak baroclinic zone, near the
leading edge of air impacted by outflow from now dissipated
convective development, boundary-layer air with seasonably high
moisture content is becoming characterized by moderate to strong
potential instability. This is being supported by steep
lower/mid-tropospheric lapse rates associated a broad plume of warm
and capping elevated mixed-layer air overspreading much of the Great
Plains.
Based on latest model output and objective analysis, the northern
periphery of the stronger capping may now be north of the surface
front, roughly near/northwest of the Dickinson through Garrison and
Minot vicinities. However, large-scale scale ascent associated with
lower/mid-tropospheric warm advection, a subtle mid-level short wave
perturbation, and localized area of enhanced low-level convergence
might be sufficient to overcome mid-level inhibition and support the
initiation of at least isolated thunderstorm development late this
afternoon. If this occurs, there appears potential for rapid
intensification, and the evolution of a large supercell, in the
presence of moderate to strong deep-layer shear beneath 30-40 kt
southwesterly flow around 500 mb.
The environment appears conducive to the potential for large hail,
locally damaging surface gusts, and, despite modest low-level
hodographs, a risk for a couple of tornadoes.
..Kerr/Hart.. 08/07/2025
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...BIS...
LAT...LON 47540379 48680138 48179986 47190026 46830139 47080353
47540379
MOST PROBABLE PEAK TORNADO INTENSITY...85-115 MPH
MOST PROBABLE PEAK WIND GUST...65-80 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN
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