Severe Storm Outlook Narrative (AC)
Issued by NWS

Current Version |  Previous Version |  Text Only |  Print | Product List |  Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
413 ACUS11 KWNS 241658 SWOMCD SPC MCD 241657 ILZ000-MOZ000-IAZ000-241900- Mesoscale Discussion 0929 NWS Storm Prediction Center Norman OK 1157 AM CDT Fri May 24 2024 Areas affected...northern and central Missouri...west-central Illinois Concerning...Severe potential...Watch possible Valid 241657Z - 241900Z Probability of Watch Issuance...60 percent SUMMARY...Widely scattered storm development is forecast this afternoon coincident with an increasing risk for severe weather. Large to very large hail is possible (1-2.5 inches in diameter), strong/locally damaging to severe gusts (55-70 mph), and possibly a couple of tornadoes. DISCUSSION...Visible satellite imagery shows a swelling cumulus field across far eastern KS and northwest/western MO ahead of a cold front gradually pushing east across the lower MO Valley. A morning severe MCS --currently approaching Lake Michigan-- has resulted in an outflow boundary becoming draped from central IL westward into northeast MO and arcing northwestward into far south-central IA. South-southwesterly low-level flow will advect higher theta-e as the airmass destabilizes gradually from southwest to east-northeast across northeast MO and west-central IL. Forecast soundings for early this afternoon show a very unstable airmass (3500 J/kg MLCAPE) across northern/central MO south of the outflow boundary. Effective shear around 30 kt will support organized storms, including supercells and severe multicells (especially once additional storms develop and congeal their outflows). The hail risk will be greatest with any supercell that develops given 8.0 deg C/km 700-500 mb lapse rates and large buoyancy. If the outflow boundary and air immediately on the cool side can modify appreciably over the next few hours, it is possible a tornado threat develops with storms that can favorably interact with the zone of augmented low-level shear. ..Smith/Guyer.. 05/24/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ILX...LSX...DVN...SGF...EAX... LAT...LON 40049403 40439299 40569103 40189029 39609006 39029019 38509115 38559270 38749395 38979432 39369437 40049403