585
ACUS11 KWNS 191748
SWOMCD
SPC MCD 191747
OHZ000-MIZ000-INZ000-191915-

Mesoscale Discussion 1333
NWS Storm Prediction Center Norman OK
1247 PM CDT Wed Jun 19 2024

Areas affected...portions of northeast Indiana...southern Lower
Michigan and northern Ohio

Concerning...Severe potential...Watch possible

Valid 191747Z - 191915Z

Probability of Watch Issuance...40 percent

SUMMARY...Scattered thunderstorms are expected this afternoon with
the potential for some clustering. Damaging gusts and isolated hail
are possible and a WW is being considered.

DISCUSSION...As of 1740 UTC, early afternoon visible satellite
imagery showed initial updrafts were deepening across parts of
eastern IN and northwestern OH along the western edge of a strong
east coast ridge. Intermixed with scattered high clouds, strong
diurnal heating is ongoing along a subtle confluence axis aiding in
further vertical development. Observational trends and hi-res
guidance suggest scattered storm development is likely over the next
couple of hours as convective temperatures are breached and
remaining inhibition is removed. 70s F surface dewpoints and steep
low-level lapse rates are supporting moderate buoyancy (1500-2500
J/kg of MLCAPE) more than adequate for strong updrafts. Area VADs
show a slight enhancement of mid-level flow along the periphery of
the broad ridge over the eastern US. While not overly strong, bulk
shear values of 20-25 kt should be sufficient for sustained
multi-cells with some potential for clustering. Drier mid-level air
and steep low-level lapse rates will be favorable for a few more
robust downdrafts capable of damaging severe gusts. A few instances
of marginally severe hail are also possible with the longer lived
and deeper updrafts given the relatively large buoyancy and somewhat
enhanced vertical shear. With the potential for some stronger
clusters of storms to develop and persist, a severe thunderstorm
watch may be needed this afternoon for portions of OH, IN and Lower
MI.

..Lyons/Smith.. 06/19/2024

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...CLE...ILN...DTX...IWX...GRR...IND...

LAT...LON   40018499 40638543 41238538 42148457 42688375 42828319
            42668254 41988301 41738293 41608256 41558212 41598182
            41588148 41408147 41308151 40698209 39828360 39808378
            39778418 40008485 40018499