textproduct: Aberdeen

KEY MESSAGES

- Thursday and Friday, highs will reach the upper 70s to low 80s. These temperatures are 20-25 degrees above normal, and will approach record highs.

- Rain chances return Friday with a 20-40% chance of light showers over northeastern SD and western MN. Additional chances for showers come Saturday along a cold front, where there is a 10-40% chance to see a tenth of an inch of rain over northeastern SD and western MN.

- Southerly winds increase Friday, with widespread 30-40 mile per hour gusts expected during the afternoon. There is a roughly 10-30% chance for gusts to reach 45 miles per hour or more over eastern South Dakota and western Minnesota.

- Warm conditions and strong winds will lead to elevated fire weather concerns across central South Dakota Thursday, with more widespread concerns Friday.

DISCUSSION

Issued at 236 PM CDT Wed Oct 21 2026

High pressure center to the north is in control today, keeping northeasterly winds gentle this afternoon. As the high pressure slides eastward, winds will shift overnight tonight to become southeasterly. Mostly clear skies are also in place today and into tonight, with just some scattered mid to high clouds expected. Strong humidity recovery coupled with the light winds overnight create the potential for some fog development early Thursday morning. Thus far hi-res model guidance is split on the fog potential, with mainly the REFS showing some visibility reductions over central South Dakota. However, can't rule out fog over both the James River Valley and far northeastern South Dakota/western Minnesota either due to lighter winds compared to the rest of the forecast area and a favorable direction for upslope flow helping with the development.

On Thursday, the high pressure center in control of the region will progress eastward, causing a tightening of the pressure gradient behind it. Southerly wind gusts will therefore increase Thursday afternoon, reaching up to 25-35 miles per hour by the afternoon. The strongest gusts are expected mainly along and west of the Missouri River, and may persist into the overnight hours. An upper-level ridge overhead will support the continuation of above normal temperatures. Highs reaching into the upper 70s to low 80s may approach daily record highs.

A southerly low-level jet will move over eastern South Dakota and western Minnesota Friday, bringing about a further increase in winds over much of the forecast area. There is a fair degree of agreement on the jet topping out around 850mb at 40-50 miles per hour. This will result in near-Wind Advisory gusts (45 miles per hour or higher) near the surface in the afternoon. High-resolution ensembles within range of the event give a roughly 10-30% chance (with localized areas up to 40-50%) to see gusts of 45+ miles per hour Friday afternoon, so the event remains somewhat marginal at this point. The jet will advect warm, moist air into the region, pushing 850mb temperatures up to 20 degrees Celsius and PWATs to 1.25"+, both well above the 90th percentile for this time of year. Naturally this will create another day of near-record temperatures at the surface (highs in the upper 70s to low 80s) and widespread dew points in the 50s. The low-level jet will also be responsible for supporting some light rain shower development over northeastern South Dakota and western Minnesota Friday morning and afternoon. As the jet continues overnight Saturday, there is potential for some localized downslope winds over the eastern side of the Prairie Coteau reaching upwards of Advisory criteria.

With strong winds both Thursday and Friday coupled with the abnormal heat, elevated fire weather conditions will be in place during those afternoons. Thursday, Grassland Fire Danger will reach the High category over central and parts of north central South Dakota. Coverage of High Grassland Fire Danger will expand to cover the entire forecast area Friday afternoon, with some pockets of Very High Grassland Fire Danger possible. The high dew points (up into the 50s) will keep minimum afternoon humidity to the 40-55 percent range both days.

On Saturday, a cold front is set to move across the forecast area. Along the boundary, additional rain showers are expected. Behind the cold front, there is high confidence in a significant temperature drop into the start of next week. While there's naturally still a bit of uncertainty, highs are set to be in the upper 40s to low 50s, about 5-10 degrees below normal for this time of year. An upper- level low will track northeast into the region next week, potentially bringing additional precipitation chances during the early week. An early look at soundings does show some potential for saturation in the DGZ and a sub-freezing profile down to the near- surface layer during the overnight hours, so some of the area may potentially see the first flakes of the season.

AVIATION /18Z TAFS THROUGH 18Z THURSDAY/

Issued at 1206 PM CDT Wed Oct 21 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are expected through the period. The only caveat to this statement is a minor signal in the potential for some fog overnight tonight. However, confidence is not high enough at this time to warrant a mention in the TAFs. Otherwise, winds will generally remain out of the northeast through the day today, with a shift to more southeasterly flow overnight tonight. Gusts are expected to remain below 20 knots through the TAF period.

ABR WATCHES/WARNINGS/ADVISORIES

SD...None. MN...None.