ACUS11 KWNS 150647 SWOMCD SPC MCD 150647 ILZ000-IAZ000-150815- Mesoscale Discussion 0444 NWS Storm Prediction Center Norman OK 0147 AM CDT Wed Apr 15 2026 Areas affected...Southern IA into far northwest IL Concerning...Severe Thunderstorm Watch 115...117... Valid 150647Z - 150815Z The severe weather threat for Severe Thunderstorm Watch 115, 117 continues. SUMMARY...An isolated severe threat may persist overnight, though an eventual weakening trend is expected. DISCUSSION...Within an extensive area of convection across Iowa, a small north-south oriented line segment has evolved south of Des Moines. This line segment earlier produced a gust of 52 kt at Creston, IA, and remains relatively vigorous within a moderately unstable and favorably sheared environment. A threat for locally damaging wind and possibly marginal hail could continue in the short term, before increasing MLCINH eventually leads to a weakening trend and/or a tendency for outflow to surge ahead of convection with time. A marginal severe threat could persist across eastern portions of WW 115 after its 07 UTC expiration, but this watch may be allowed to expire unless a short-term uptick occurs. An isolated severe threat remains evident across downstream WW 117, but this watch may eventually be cancelled early if a definitive weakening trend is observed. ..Dean/Smith.. 04/15/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DVN...DMX... LAT...LON 41429342 41649127 41679054 41709018 41359023 40929072 40699161 40599320 40729360 40749374 40909358 41429342 MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN