732 FXUS63 KABR 291823 AFDABR Area Forecast Discussion National Weather Service Aberdeen SD 123 PM CDT Mon Jun 29 2026 .KEY MESSAGES... - A Heat Advisory remains in effect through early this evening across far northeast South Dakota and west central Minnesota for heat index temperatures in the 100F to 107F degree range. - There is a Slight (2 of 5) to Marginal Risk (1 of 5) for severe weather this afternoon into this evening across north portions of central and northeast South Dakota and west central Minnesota, as well as a portion of central South Dakota. Main hazards are thunderstorm wind gusts up to 75 mph and 1-2in hail. Additionally, the development of a tornado or two cannot be ruled out. - There is a Marginal Risk (1 of 5) for severe weather late Tuesday night through the day Wednesday across portions of central and northeast South Dakota and west central Minnesota. Main hazards are large hail up to 1 inch in diameter and wind gusts of 60 mph. - Western U.S. wildfire smoke (aloft) will be over the region through Wednesday; potentially longer depending on how steering flow winds evolve this week. Some minor concentrations of near surface smoke could happen late Tuesday night into the day on Wednesday. - Above normal temperatures are expected to persist for most of this week. With highs in the mid 80s to mid 90s and dewpoints well into the 60s, and even 70s for some locations, especially from Thursday onward, heat-related illnesses become a concern. && .DISCUSSION... Issued at 121 PM CDT Mon Jun 29 2026 At 1 PM CDT, skies are smoky and partly cloudy. Temperatures are warming through the 70s and 80s. Heat index values are beginning to respond to the combination of warming temperatures and dewpoints in the 70s; with readings rising into the mid to upper 90s. The Heat Advisory continues. Winds have a southeast component this afternoon, generally 10 to 20 mph with some occasional gusts up to 30 mph. A frontal boundary is positioned east of the Missouri River valley, slowly working its way east. This is the focusing mechanism for a potential next round of thunderstorms by late this afternoon/early this evening. If convection initiates in the eastern part of this CWA before pushing off into Minnesota, large hail and damaging winds would be the primary concerns. Low level shear and CAPE appears to activate across the far eastern forecast zones, as well, aoa 22Z today. This would tend to increase the risk of a tornado or two with any storms that form. However, with warm mid-level (700hpa) temperatures between +12C and +15C positioned across the eastern half of the CWA late this afternoon through late this evening, thunderstorms are not likely to develop (capping too strong). This boundary is modeled to sag south into Nebraska on Tuesday and stall out. Model progs then show it working back northward into the CWA late Tuesday night into Wednesday morning as a warm front. Expecting this could be the next chance for showers and thunderstorms (mid-level WAA coupled with low level moisture advection, a warm-frontal zone of ascent and perhaps even some energy aloft). After that, the forecast should be dry until Thursday afternoon when the next potential round of storms could get going. Current model timing has shortwave energy entering the region both Thursday and Friday, so both of these afternoons/evenings could have some strong thunderstorms to deal with. It's not clear whether an additional round of storms could be putting a dent in 4th of July plans Saturday afternoon/evening, but there are PoPs (~20-40%) in the forecast for Friday afternoon/evening. Things should dry out after that for Sunday and Monday when the upper ridge east of here sloshes back to the west. Cluster analysis shows this well. In fact, clusters analysis would have one believing that the upper ridge will slosh back to the east at some point during that first full week of July. How warm/uncomfortable it gets outside is tied to the strength/position of this upper ridge, which is not shown to be all that strong just now for the weekend into next week. Presently, Thursday and Friday may be the only days that see the temperature warm to 90 or above. Heat Index values from Tuesday onward do not appear to be all that much of a concern at the moment. The latest HRRR output shows this smoke aloft never really going away. Not putting too much weight on its output late in the period, but it does prog both near surface smoke and smoke aloft to cork- screw around and start into this region from the northwest, as well as from the southwest, by Wednesday morning. If the concentrations of near surface smoke being generated in the 12Z HRRR run end up panning out, some visby restriction and air-quality/health concerns may start popping up. && .AVIATION /18Z TAFS THROUGH 18Z TUESDAY/... Issued at 1226 PM CDT Mon Jun 29 2026 Terminals KABR,KATY,KPIR,KMBG A mix of VFR/MVFR cigs right now for KPIR/KABR/KATY/KMBG is forecast to become all VFR by mid-afternoon. Monitoring a frontal boundary stuck back along the Missouri River valley (KPIR/KMBG) right now. It is forecast to move east into Minnesota through mid-evening, turning winds from the southeast to the west or southwest. This boundary could be the focus for thunderstorm re-development late this afternoon through late this evening mainly across northeast South Dakota (KABR/KATY) into west central Minnesota. Thunderstorm wind gusts of 60-75mph and 1-2in diameter hail are the primary threats. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...Heat Advisory until 8 PM CDT this evening for SDZ008-020>023. MN...Heat Advisory until 8 PM CDT this evening for MNZ039-046. && $$ DISCUSSION...10 AVIATION...10