407 FXUS63 KFSD 051953 AFDFSD Area Forecast Discussion National Weather Service Sioux Falls SD 253 PM CDT Fri Jun 5 2026 .KEY MESSAGES... - A low (<20%) chance of storms through this evening over southwest Minnesota, but the threat for severe weather with this is very low and conditional. If a severe storm can develop, half dollar sized hail and 60 mph wind gusts will be possible. - A system wraps north Sunday into Monday and will bring scattered showers and thunderstorms to the area. Severe weather chances are currently low. - Temperatures heat up this weekend into next week. There is an increasing chance (30-70%) of highs exceeding 95 degrees mainly near and west of the James River by Tuesday and especially Wednesday. Be prepared to enact any heat related safety measures. && .UPDATE... Issued at 146 AM CDT Fri Jun 5 2026 A decaying MCS will continue to drift east through the early morning hours. Additional rainfall amounts will be on the lighter side. Model trends continue to push the chances for stronger updrafts to the south of the area for this afternoon and evening in the wake of this MCS, so other than roughly near and south of a Sioux City to Storm lake line the chances for any severe weather today are very low. A few updrafts could develop in other parts of mainly northwest IA with a very small chance to reach severe levels. Otherwise a fairly pleasant summer day is ahead for most locations with highs in the 80s and fairly light winds. This will lead into a quiet and warmer Saturday as a nose of high pressure dips south into the area. Highs from the upper 80s to mid 90s in most locations. && .DISCUSSION... Issued at 245 PM CDT Fri Jun 5 2026 Storms have developed over far western Minnesota and are moving east-southeast this afternoon. This activity is associated with an upper wave that will be moving across the northern Midwest into the Great Lakes region through tonight. With the better upper level support off to our northeast, the chance for thunderstorms is low and the chance for severe weather is even lower in our southwest Minnesota counties. If a storm were to sneak in (<20% chance), then it will have around 1,000 to 1,500 J/kg of MLCAPE and around 35-40 kts of shear to work with, which could support an isolated 60 mph wind gust or instance of half dollar hail. The main time frame for this highly conditional threat is through 9-10 pm. Otherwise, tonight will feature mainly clear skies with calm winds, and thus patchy fog will be possible in spots. The NBM favors areas near and east of I-29 for fog while the REFS favors north of I-90. Would lean towards REFS on this one as there is plenty of moisture north of I-90 left behind from recent thunderstorms and these areas will cool the fastest towards the dew point tonight. Clouds may also linger longer near and south of Highway 20 as well tonight associated with storms to our south, so this could limit fog potential there. Speaking of those storms, they look to develop over eastern Nebraska and southwestern Iowa through the evening hours, but this is expected to remain south of the area through tonight. One thing worth watching with these storms is any potential outflow boundaries that are left behind that could affect weather for Saturday. Some CAMs including the 05.12Z HRRR and RRFS-2 show some storms developing over the Highway-20 corridor tomorrow afternoon and evening, perhaps associated with one of these potential boundaries lifting northward into our area, so that will be something to watch. But when looking at overall chances according to the REFS and HREF, the chance of rain is less than 20%. So otherwise, dry, sunny, and very warm weather is expected on Saturday, and with ridging aloft, look for highs in the upper 80s to lower 90s, hottest along the Missouri River Valley. On Sunday, guidance shows and upper low moving north across the central Plains. To the west, a surface low will drag a cold front into western South Dakota. The EC Ensemble shows an up to 60% chance of measurable precipitation as early as Sunday morning over northwest Iowa associated with aforementioned upper low but most other guidance brings better rain chances into the afternoon. Cloud cover ahead of this system will mean poor destabilization ahead of any thunderstorms over northwest Iowa, so the severe weather threat potential looks low at this time. The cold front off to our west will help fire off strong to severe storms over the northern High Plains Sunday afternoon/evening, and some of these will try to push into areas west of I-29 into early Monday morning. However, waning instability and storms potentially outrunning the best shear will mean the chances for severe weather locally with this is also fairly low at this time. The main story heading into the next work week will be the building heat, starting Tuesday. That's when highs look to climb into the 90s area-wide, with the potential for highs nearing 100 along the Missouri River Valley. Then Wednesday may be even hotter as a front turns winds more southwesterly in south- central South Dakota. The NBM has come down a little bit in temperatures, but looking at the LREF, it has a 30-50% chance of highs above 95 in south-central South Dakota and then a 40-70% chance on Wednesday in that area. One limiting factor to this heat being realized on Wednesday is that storms may form along and ahead of the front and so that could affect heating. Either way, keep up to date with the latest forecast and be prepared to take heat related safety measures! && .AVIATION /18Z TAFS THROUGH 18Z SATURDAY/... Issued at 1225 PM CDT Fri Jun 5 2026 Isolated showers and storms are possible into this evening over southwest Minnesota and the Highway 20 corridor in northwest Iowa/far northeast Nebraska. Coverage of storms is expected to be low enough to preclude any thunder mention at KSUX at this time, but trends will be monitored. Could see some fog develop tonight into tomorrow morning, but the chance of this occurring is roughly 20-30% across the area, too low to include mention in the TAFs at this time. Winds will be fairly light through the period, increasing towards tomorrow afternoon out of the east- southeast. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. IA...None. NE...None. && $$ UPDATE...08 DISCUSSION...Samet AVIATION...Samet