Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Jun 12 2025 23:25:41 AWUS01 KWNH 122325 FFGMPD MNZ000-SDZ000-NDZ000-130400- Mesoscale Precipitation Discussion 0425 NWS Weather Prediction Center College Park MD 724 PM EDT Thu Jun 12 2025 Areas affected...northeastern SD into southwestern MN Concerning...Heavy rainfall...Flash flooding possible Valid 122323Z - 130400Z Summary...Localized flash flooding may occur over northeastern portions of SD into southwestern MN through 04Z. Rainfall rates of 1-2 in/hr and localized totals of 2-3 inches are possible. Discussion...Recent radar imagery through 23Z showed the recent intensification of a thunderstorm over northern Spink County (south of Aberdeen) along with scattered showers extending from the eastern ND/SD border into central MN. These cells were elevated, located north of a wavy quasi-stationary front that extended westward into eastern SD, then southwestward into northwestern NE. Lift in advance of a 700-500 mb shortwave trough (extending from northeastern MT into western SD) and advection of low level moisture via a 20-25 kt 850 mb jet has allowed for an increase in MUCAPE north of the front, aiding in the recent intensification. 850 mb winds are forecast to further strengthen a bit to near 30 kt by 03Z from the eastern SD/NE border and northward to the front, according to recent RAP forecasts, allowing for potential upstream thunderstorm development. While instability will likely remain a modest 500-1000 J/kg over northeastern SD via short term HRRR/RAP forecasts, an observed GPS PW just east of the northern SD/MN border was 1.5 inches at 22Z, near the climatological max at ABR for mid-June. The mean steering flow of cells is expected to be from the WSW to W, roughly parallel to the frontal boundary to the south, which will support repeating rounds of heavy rain from west to east. Rainfall rates of 1-2 in/hr may occur at times and there will be the potential for 2-3 inches of rain through 04Z. This rain may overlap with locally hydrologically sensitive regions, including urban centers and portions of Brown and Marshall counties, which received locally heavy rain (up to 4 inches) earlier today. Localized flash flooding could result from parts of northeastern SD into far southwestern MN through 04Z. Otto ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!77HmyaFbLjzuYrBy_F49UY2RfE7-0A4T8l6jh-1VIIl5o8lWbiugMoVq4hnScUlbA41D= MWbMjxF4ZU_-LNuFLolp_Fw$ for graphic product... ATTN...WFO...ABR...BIS...FGF...FSD...MPX... ATTN...RFC...KRF...MSR...NWC... LAT...LON 45989717 45839581 45499528 44929549 44709668=20 44639830 44569985 44980071 45630060 45959913=20 =20=20=20=20=20=20=20=20=20=20=20=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 3.20-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .