Mesoscale Discussion 0170
NWS Storm Prediction Center Norman OK
0101 PM CDT Fri Mar 14 2025
Areas affected...parts of far eastern Kansas and northeastern
Oklahoma through northwestern Arkansas...western and central
Missouri and southern Iowa
Concerning...Severe potential...Watch likely
Valid 141801Z - 142030Z
Probability of Watch Issuance...95 percent
SUMMARY...A rapidly developing squall line may initiate near of just
west of the western Missouri state border vicinity as early as 3-4
PM CDT. This will probably pose increasing potential for producing
very strong, damaging surface gusts and some severe hail while
rapidly developing northeastward through early evening. Potential
for large hail and a few tornadoes may begin to increase prior to
sunset, particularly across parts of south central through
southwestern Missouri into northwestern and north central Arkansas.
One or more severe weather watches will be needed.
DISCUSSION...In the wake of the initial, elevated convective
development, boundary-layer destabilization is ongoing in a narrow
corridor across eastern Oklahoma through eastern Kansas, within the
evolving warm sector of the deep, occluding cyclone now centered
over northwestern Kansas. This is being supported by still rather
modest low-level moisture return characterized by upper 40s to near
50F surface dew points along an ill-defined dryline, to the north of
the I-44 corridor. Still, beneath steep lapse rates associated with
warm elevated mixed-layer air, insolation is forecast to contribute
to increasing mixed-layer CAPE up to around 1000 J/kg within the
next couple hours, with continued cooling further aloft.
As an intense cyclonic mid/upper-level jet streak (including a core
in excess of 100 kt around 500 mb) continues nosing across the south
central Great Plains toward the lower Missouri Valley through early
this evening, associated forcing for ascent coupled with the
destabilization appears likely to support the initiation and
intensification of thunderstorm activity. It appears that this may
commence near the western Missouri/Kansas and Oklahoma state border
vicinity, as the dryline is overtaken by the stronger near-surface
through mid-tropospheric cooling.
Any initially discrete thunderstorm development seems likely to be
short-lived, with a rapid upscale growing line expected, probably by
20-22Z, if not perhaps a bit earlier. Given the initially modestly
deep and well-mixed boundary layer, and the strength of the
lower/mid-tropospheric flow (including 50-60 kts south to
south-southwesterly in the lowest 3-6 km AGL), the development of
strong, damaging surface gusts appears to the most certain potential
severe hazard.
The extent of the hail and tornado threat remains a bit more
unclear. However, guidance is suggestive that at least a bit more
substantive low-level moisture return ahead of the developing line,
across northwestern Arkansas into southwest and south-central
Missouri, might support increasing potential associated with these
hazards prior to 15/00Z.
..Kerr/Gleason.. 03/14/2025
