Subj : MESO: Mesoscale Discussion 0509 To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Apr 21 2025 02:54:36 ACUS11 KWNS 210254 SWOMCD SPC MCD 210254=20 ILZ000-210430- Mesoscale Discussion 0509 NWS Storm Prediction Center Norman OK 0954 PM CDT Sun Apr 20 2025 Areas affected...portions of northern Illinois Concerning...Tornado Watch 157... Valid 210254Z - 210430Z The severe weather threat for Tornado Watch 157 continues. SUMMARY...The severe threat continues across Tornado Watch 157. A couple of severe gusts are the main concern, though a tornado cannot be ruled out. DISCUSSION...A primary band of convection persists amid very strong forcing accompanying an approaching surface low and upper-level jet streak. Despite scant buoyancy, the latest LOT VAD shows a hodograph with impressive size and curvature, indicating strong low-level wind shear, driven by very strong flow just above the surface. While decreasing lightning trends suggest that storms are weakening, the intense low-level flow/shear suggests that damaging gusts may still occur wherever downward momentum transport may occur. A tornado also remains possible if a rotating updraft can ingest any remaining surface-based buoyancy. ...Squitieri.. 04/21/2025 ....Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!__37oK6d0QJdXqNEhI4mAZJIOkg_jWuiStIJdDr5JUv8Q2txVWrGmCBU-da_ggVO5XqP_S4b0= 7hy8dhynvUjxc_yBYw$ for graphic product... ATTN...WFO...LOT...ILX...DVN... LAT...LON 40568839 40928885 41308911 41708931 41948922 41998888 41828838 41428803 40988774 40608769 40498805 40568839=20 MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH MOST PROBABLE PEAK WIND GUST...65-80 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN =3D =3D =3D To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM. --- SBBSecho 3.20-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .