193 FXUS63 KABR 121733 AAC AFDABR Area Forecast Discussion...UPDATED National Weather Service Aberdeen SD 1233 PM CDT Thu Jun 12 2025 .KEY MESSAGES... - Elevated smoke remains over the region with an intermittent return of near surface smoke and visibility reductions through Friday. - Showers and thunderstorms expected through Friday morning, with the highest chances (60-90%) along and east of the Sisseton Hills Thursday afternoon and evening. - Heavy rain is possible with amounts of 1 to 2+", highest over far northeastern SD into west central MN through tonight. - There is a marginal risk (1 out of 5) for severe thunderstorms this afternoon and evening south of Hwy 12. There is a slight risk (2 out of 5) for eastern Lyman, Buffalo, and southeastern Hand counties. && .UPDATE... Issued at 1218 PM CDT Thu Jun 12 2025 Updated forecast for the 18Z TAFs below. UPDATE Issued at 1010 AM CDT Thu Jun 12 2025 Radar continues to show scattered showers over portions of north central through northeastern SD into west central MN and more spotty isolated rain showers over south central MN pushing northeast. Cloudy skies continue over the northern half of the CWA with a bit of sun starting to peak out over south central SD, which will aid in instability for the convection expected later on this afternoon. We are still on track for the potential of severe thunderstorms firing up late this afternoon and evening along and south of the warm front with the marginal risk stretching from Eagle Butte and eastward through Milbank. CAMs indicate the strongest storms over south central SD. This is where the SPC has updated the severe potential to a slight risk (level 2/5) including portions of Lyman, Buffalo, and Hand counties. Main threats include large hail, quarter size or larger, wind gusts of 60-70 mph, and a tornado or two cannot be ruled out in this slight risk area. Instability really drops off along and north of highway 12 so sub severe storms expected in this area. Showers and thunderstorms will continue to shift east and northeast with the front and low with precip diminishing southwest to northeast over the CWA early Friday morning. Updated the pops to match the radar and CAMs over the next few hours otherwise, forecast remains on track. && .SHORT TERM /TODAY THROUGH FRIDAY AFTERNOON/... Issued at 420 AM CDT Thu Jun 12 2025 Rain and thunderstorms continue to expand north and east of two features: a warm front draped along the NE/SD border and a 700 mb low currently over eastern MT with some shortwave energy ejecting out ahead of it. For now, the thunderstorms are pretty weak. Monitoring for heavy rain and potential flooding at the moment as rain trains over south central SD and the I-90 corridor. This heavy rain threat will spread northeast this afternoon through tonight as the front creeps north and the 700 mb low moves into eastern ND/MN. Additionally, thunderstorms may be rather slow moving. PWATS remain over an inch along and east of the Coteau. As the frontal boundary stretches northeast from Chamberlain to Spink/Clark county by 21z, there will be a narrow corridor of enhanced CAPE around 1000 to 2000 J/kg. Outside of this corridor, CAPE has a sharp gradient and remains sub-optimal for severe storms. Shear, on the other hand, is abundant across the region at 45 to 60 kts. Even though SPC took out the tornado threat from its outlook, NAM keeps a narrow corridor of 1 to 4 STP on the boundary over Buffalo, Hand and Hyde counties. While perhaps not the primary concern, there is a non-zero chance of tornadoes along the frontal boundary. Lapse rate between 7 and 8 behind the frontal boundary along with the shear could lend themselves to some stronger winds. Winds also shift to the southwest ahead of the boundary tonight along the Coteau, setting up some stronger downslope winds regardless of thunderstorm activity. This system exits/retreats on Friday with just some scattered activity remaining outside of sfc high pressure over the northeast. && .LONG TERM /FRIDAY EVENING THROUGH WEDNESDAY/... Issued at 420 AM CDT Thu Jun 12 2025 An active weather pattern can be expected through the long term portion of the forecast, and perhaps into the following weekend. A persistent trough off the coast of British Columbia will cause a broad west coast trough through a majority of the long term. While upper level ridging does develop over the nation`s midsection, the northern plains will likely experience several ridge riding shortwaves. Timing of the shortwave are often problematic as minor differences in model data causes a broadbrush approach to NBM pops. The ECMWF brings increasing instability into the CWA Sunday through Tuesday, which may support multiple rounds of strong storms. The deep layer shear may be lacking some on Sunday, but become more robust Monday and Tuesday. Our lack of severe weather so far this season appears to be over. && .AVIATION /18Z TAFS THROUGH 18Z FRIDAY/... Issued at 1218 PM CDT Thu Jun 12 2025 Terminals KABR,KATY,KPIR,KMBG Scattered showers continue over northeastern SD into west central MN with spotty showers from north central through south central SD. Additional shower and thunderstorm development is expected this afternoon with rain continuing through early Friday. This will affect all taf sites as a 700 mb low sits off to our northwest and a frontal boundary to the south. Cigs are expected to range between MVFR/IFR through the TAF period with KPIR at VFR then MVFR/IFR with and behind the frontal boundary. Any heavier rain cigs could fall lower. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. && $$ UPDATE...MMM SHORT TERM...20 LONG TERM...SD AVIATION...MMM