


Area Forecast Discussion
Issued by NWS Aberdeen, SD
Issued by NWS Aberdeen, SD
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052 FXUS63 KABR 061743 AAC AFDABR Area Forecast Discussion...UPDATED National Weather Service Aberdeen SD 1243 PM CDT Sun Jul 6 2025 .KEY MESSAGES... - There is a 20-50 percent chance for afternoon and evening thunderstorms on Monday, mainly across portions of central and northeast South Dakota and west central Minnesota. There is a slight risk (level 2 out of 5) for severe thunderstorms capable of producing localized large hail and thunderstorm wind gusts. - The weather pattern stays active next week with additional thunderstorm chances by Thursday night into Friday. - Seasonal temperatures are expected during the 7 day forecast, with the exception of Wednesday and Thursday, when high temperatures could bump back up into the low to mid 90s throughout and west of the James River valley. && .UPDATE... Issued at 1239 PM CDT Sun Jul 6 2025 The aviation discussion has been updated for the 18Z TAFS. UPDATE Issued at 1028 AM CDT Sun Jul 6 2025 Rain showers continue to move through south central sections of SD this morning. This activity will continue to rest of the morning hours and move out of our forecast area by early afternoon. Cooler temperatures and lower humidity values will be the main themes through the afternoon. The going forecast for the remainder of today remains mostly on track. Outside of some minor adjustments to PoPs and Sky grids, no significant changes are planned at this time. && .DISCUSSION... Issued at 446 AM CDT Sun Jul 6 2025 As of 3AM, there are currently showers over areas west of the Missouri River, with some storms over south central SD. This precipitation is currently moving south while starting to dissipate. The precipitation will move over areas just east of the Missouri river, but it looks to stay west of the James River Valley this morning. There is more precipitation and storms over western SD moving towards central SD, though they look to be weakening as they get closer. This will lead to scattered chances for mainly showers over central and south central SD into and through the morning, with a chance for a storm or two. The upper-levels have semi-zonal flow over SD today into Monday, with a weak high pressure developing at the surface moving in behind the departing showers this morning. This high pressure, as well as a lack of a lifting mechanism, will help to keep precipitation and storms from developing Sunday afternoon into the overnight hours. Additionally, the weak high pressure over the area will help to keep winds light, with gusts mostly staying below 15 mph today. An upper-level shortwave is forecast to move over SD Monday afternoon, which helps to support a surface boundary moving into north central SD during the afternoon and through the state into the evening. Models currently show instability values of 1000 to 2000 J/kg over central and eastern SD on Monday, with some variation in the location of the highest values. The models have adequate moisture that moves into central and eastern SD from a tongue of moisture currently over eastern MT/WY, however they vary where that moisture moves over and when it start to interact with the boundary. With models variation in a key component to storm development, it does lower the confidence in storm timing, location, and strength. Even with this lower confidence, the Storm Prediction Center has a slight risk (level 2 of 5) for severe storms to develop over central and eastern SD Monday afternoon into the evening. With bulk shear of 30- 40kts in the models, storms that do develop could be multicell or become supercellular. Storm motion on model hodographs is showing a movement to the east southeast around 20kts. This storm motion will keep any storms that develop close to if not along the boundary as the boundary pushes through central and eastern SD. This could lead to training storms or storms that eventually take on a linear structure, leading to a higher risk of strong winds. An upper-level ridge looks to start moving towards SD by the mid- week, bringing in weak high pressure to the area. This then starts to advect warmer temperatures into central and eastern SD, which will help to increase surface temperatures from the low to mid 80s at the beginning of the week into the low to mid 90s Wednesday and Thursday. While there is weak surface high pressure over central and eastern SD, it doesn`t fully rule out precipitation and storm chances. It is possible for a few ridge runner shortwaves to move up over the north central plains upper level ridge, which could lead to one or more surface frontal passages. This could generate additional late week showers and storms. As we get closer to the mid-week, the lack of precipitation in the forecast could change, so an eye will need to be kept on this time. && .AVIATION /18Z TAFS THROUGH 18Z MONDAY/... Issued at 1239 PM CDT Sun Jul 6 2025 Terminals KABR,KATY,KPIR,KMBG VFR conditions are expected at all terminals through this TAF cycle. Increasing chances for precipitation on Monday prompted the addition of PROB30 groups at KPIR during the morning. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. && $$ UPDATE...Vipond DISCUSSION...12 AVIATION...Vipond