ACUS11 KWNS 191731 SWOMCD SPC MCD 191731 INZ000-KYZ000-ILZ000-TNZ000-MOZ000-ARZ000-191930- Mesoscale Discussion 0786 NWS Storm Prediction Center Norman OK 1231 PM CDT Tue May 19 2026 Areas affected...Lower Ohio River Valley Concerning...Severe potential...Watch possible Valid 191731Z - 191930Z Probability of Watch Issuance...40 percent SUMMARY...Thunderstorm coverage is expected to increase this afternoon across much of the Ohio River Valley as daytime heating brings the boundary layer to convective temperatures. These storms will primarily be capable of damaging straight-line winds and hail. DISCUSSION...Thunderstorms have begun to develop within moist and uncapped boundary layers where MLCAPE exceeds 2500 J/kg. Convective coverage is expected to increase throughout the afternoon, though will remain disorganized initially due to a lack of deep-layer shear. Still, large environmental DCAPE, steep low-level lapse rates, and relatively high PWATs will support strong downdrafts capable of damaging wind gusts. Localized corridors of increased threat could occur with any local organization along leading-edge outflow boundaries or with outflow boundary interactions. ..Halbert/Hart.. 05/19/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ILN...LMK...IND...PAH...ILX...MEG...LSX... LAT...LON 37589038 38458917 39578772 39918713 40028678 40098648 40098622 40028577 39748540 39228521 38588528 38138563 37308700 36448861 36388874 36108926 36118947 36148962 36228993 36469026 36739039 37109047 37589038 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN