MD 0318 CONCERNING SEVERE POTENTIAL…WATCH UNLIKELY FOR PORTIONS OF CENTRAL ILLINOIS INTO WESTERN INDIANA
Mesoscale Discussion 0318
NWS Storm Prediction Center Norman OK
0738 PM CDT Sun Mar 31 2024
Areas affected…portions of central Illinois into western Indiana
Concerning…Severe potential…Watch unlikely
Valid 010038Z – 010245Z
Probability of Watch Issuance…20 percent
SUMMARY…A long-lived supercell may persist for at least a few more
hours across central and eastern IL into western IN with severe
hail. The severe weather threat is expected to remain localized
through evening.
DISCUSSION…A long-lived supercell continues to traverse a diffuse
warm-front over central IL, where upper 60s/mid 50s F surface
temperatures/dewpoints are boosting MLCAPE/MUCAPE to 500 J/kg (per
00Z mesoanalysis). Though CAPE profiles are thin (based on the
latest RAP forecast soundings and the 00Z observed ILX sounding),
modestly curved low-level hodographs with mid/upper-level elongation
suggest that vertical wind shear remains strong (i.e. 60+ kts of
effective bulk shear). While the supercell will likely remain
outflow dominant, efficient severe hail production should continue
for at least a few more hours across central IL into western IN
before the low-level jet veers, reducing convergence along the front
and potentially supporting weakening convective potential later this
evening. In the meantime, the severe threat may be constrained to
this lone supercell. Convective trends will continue to be monitored
for the need of a WW issuance, but current thinking is that the
severe threat should remain localized over central IL/IN this
evening.
..Squitieri/Guyer.. 04/01/2024
…Please see www.spc.noaa.gov for graphic product…
ATTN…WFO…IND…ILX…
LAT…LON 39588894 39878942 40138937 40228902 40108806 39808662
39678615 39308599 38978631 39018688 39268815 39588894
