Mesoscale Discussion 0882 NWS Storm Prediction Center Norman OK 0755 PM CDT Tue May 21 2024 Areas affected...parts of west central Illinois and northeastern through southwestern Missouri..northeastern Oklahoma and northwestern Arkansas Concerning...Tornado Watch 278...280... Valid 220055Z - 220300Z The severe weather threat for Tornado Watch 278, 280 continues. SUMMARY...Stronger thunderstorm development, including a few supercells, may become increasingly confined to portions of northeastern Oklahoma and northern Arkansas/adjacent southern Missouri through 9-11 PM CDT. A new severe weather watch may be needed across parts of northern Arkansas soon. DISCUSSION...The cold front appears to have overtaken the dryline across western into central Missouri and northeastern Oklahoma, with little appreciable increase in thunderstorm development. Widely scattered strong storms persist, including a few supercells, but an initial corridor of drier/more stable air across parts of south central and east central Missouri into west central Illinois remains a complicating factor for maintenance of this activity through mid to late evening. A more recent flare-up of convection immediately to the southwest through northwest of St. Louis may have been aided by weakening inhibition associated with leading edge of mid-level cooling near the eastern periphery of the corridor of drier air, further complicating the maintenance of strong convection beyond the next hour or two. Strongest thunderstorm development may begin to become focused ahead of the southeastward advancing cold front, on the southern periphery of the cyclonic mid-level flow and east of the dryline, across northeastern Oklahoma and northern Arkansas through 9-11 PM. This may include a few supercells accompanied by a risk for severe hail, locally strong surface gusts and potential for a tornado or two. ..Kerr.. 05/22/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PAH...MEG...LSX...DVN...LZK...SGF...EAX...TSA... LAT...LON 40539230 40069086 39989081 37589146 37109112 36609007 35289056 34749480 35429576 36679464 39489283 40539230