


Area Forecast Discussion
Issued by NWS Aberdeen, SD
Issued by NWS Aberdeen, SD
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454 FXUS63 KABR 092353 AAA AFDABR Area Forecast Discussion...UPDATED National Weather Service Aberdeen SD 653 PM CDT Wed Jul 9 2025 .KEY MESSAGES... - Enhanced/Slight risk (level 3/2 of 5) for severe storms across the region into the evening hours. Hail up to 2 inches in diameter possible over central/north central SD late this afternoon, with gusts up to 75 mph into this evening. - Heat and humidity today and Thursday (especially over central South Dakota), with highs in the 90s and heat indices approaching 100 degrees. - Marginal Risk (level 1 of 5) for severe storms Thursday/Thursday night. Main risks are hail up to around quarter size and wind gusts of 60 mph. && .UPDATE... Issued at 640 PM CDT Wed Jul 9 2025 The aviation discussion has been updated for the 00Z TAFS. && .DISCUSSION... Issued at 345 PM CDT Wed Jul 9 2025 Convection is beginning to fire along the surface boundary across northwest SD into southwest ND. Swath of very unstable air with MLCAPE values in excess of 4000 J/KG lies from central ND, southeast into the James River valley. Bulk shear values are around 30 knots over western SD. So, although the current storms are not developing over the most unstable air, anything that moves closer to central SD will be approaching very buoyant air. Parameters continue to support potential for large hail up to 2 inches in diameter across central SD, plus a strong wind threat up to around 75mph also over central SD eastward into the James River valley. Severe watch 498 is already in effect across central SD into the evening hours. Also for this afternoon/evening, went ahead and issued a Heat Advisory as several locations were in that 100-108 heat index range, a bit higher and more expansive than what the forecast looked like this morning. Dewpoints are a bit higher than forecast in some areas, leading to the higher heat indices. Also, actual air temperatures are flirting with 100 over central SD. More potential for precipitation and perhaps strong/severe storms arrives Thursday/Thursday night. Although, the timing of the mid- level wave and associated best lift/ascent may be later in the evening, thus leaving more widespread coverage to hold off until the overnight hours. Cold front moves through the region on Friday, bringing in cooler air as 850mb temps drop into the low to mid teens C. High temperatures drop back into the upper 70s to low 80s on Friday, along with lowering dewpoints. && .AVIATION /00Z TAFS THROUGH 00Z THURSDAY/... Issued at 640 PM CDT Wed Jul 9 2025 Terminals KABR,KATY,KPIR,KMBG An overall prevailing condition of VFR can be expected at all terminals through this forecast cycle. Continuing to monitor TSRA/+TSRA entering central sections of South Dakota early this evening. KMBG is the only site that will imminently be affected by this activity. So, included VCTS mention right at the beginning of the TAF valid period with a TEMPO group for +TSRA that will be capable of producing vsbys down to at least MVFR or potentially lower into IFR depending on the intensity of the activity. KPIR will have the potential to see similar conditions later this evening. Farther east, a little more uncertain but retained PROB30 groups at KABR/KATY by late evening. Some of the stronger cells will still be capable of producing large hail and strong thunderstorm wind gusts in excess of 60 knots. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...Heat Advisory until 8 PM CDT /7 PM MDT/ this evening for SDZ003>006-009-010-015>018-033>037-045-048-051. MN...None. && $$ UPDATE...Vipond DISCUSSION...TMT AVIATION...Vipond