Subj : MESO: Mesoscale Discussion 2250 To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Dec 06 2025 18:26:29 ACUS11 KWNS 061826 SWOMCD SPC MCD 061825=20 IAZ000-MNZ000-NEZ000-SDZ000-070030- Mesoscale Discussion 2250 NWS Storm Prediction Center Norman OK 1225 PM CST Sat Dec 06 2025 Areas affected...Far southeast South Dakota and northwestern Iowa Concerning...Heavy snow=20 Valid 061825Z - 070030Z SUMMARY...Periods of heavy snowfall are developing across portions of far southeastern SD, and will continue to expand into northwestern IA within an hour or two. Snowfall rates of 1 to 1.5" per hour can be expected. DISCUSSION...An area of moderate to heavy snow is expected to broaden this afternoon through this evening across northwestern IA, as a mid-level shortwave trough approaches. Increasing DPVA will accompany this feature, in addition to strong isentropic ascent. Most NWP models and forecast soundings suggest omega will peak within the dendritic growth zone through ~22Z over northwestern IA. HREF probabilities of QPF greater than 0.10" per hour, combined with snow to liquid ratios around 15-20 to 1, also support this time frame for the heaviest snowfall. ...Barnes.. 12/06/2025 ....Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!8GLeQPnh-l-nf0gh46V9ss-LrK4Kjf_Hv-S6zhVT2FlS5bEYmdN9rhqIOMgVQDa2phEo0eMHu= p2Uore8U2fC4Y2zlQk$ for graphic product... ATTN...WFO...DMX...FSD...OAX... LAT...LON 43709693 43699633 43629615 43589590 43509545 43439511 43249476 43069448 42829426 42399452 42339494 42149520 42109535 42119548 42159557 42189572 42229581 42269592 42269606 42339633 42429642 42559654 42699686 42849722 42999725 43449725 43709693=20 =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 3.28-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .