textproduct: Aberdeen

KEY MESSAGES

- Light snow expected to slide southeast this morning through this evening. Accumulations of up to 1 inch will be possible.

- Another round of light accumulating snow moves in on Wednesday with generally less than an inch expected.

- Gusty northwest winds develop on Wednesday ranging from 35-50 mph with the strongest winds expected across central South Dakota. Blowing snow and reduced visibilities will be possible.

- Very cold temperatures and dangerous wind chills expected Thursday through Sunday morning. The coldest period will be Friday with wind chills Friday morning ranging in the thirties to forties below zero. Actual high temperatures for Friday are forecast to range from zero to the teens below zero.

SHORT TERM /TODAY THROUGH WEDNESDAY AFTERNOON/

Issued at 543 AM CST Tue Jan 20 2026

Sfc high pressure remains in control across the eastern Dakotas and western MN early this morning. Clear skies across our far eastern zones have allowed temperatures to fall into the single digits below zero. Some locales late last evening fell into the double digits below zero across northeast SD. However, increasing low to mid level cloudiness from the west has started to move into our eastern zones and has stabilized temperatures. Cloud cover will continue to increase this morning as the next wave makes its way down into our region.

Sfc low pressure remains anchored on a northwest to southeast oriented stationary front over southeast MT/northeast WY/western SD. This disturbance is progged to track southeast along the sfc boundary into western SD this morning and into NE this afternoon. An inverted sfc trough, extending north and northeast of this low will slide across our forecast area midday through the afternoon. A swath of light snow is expected to spread east-southeast from north central sections of SD into parts of central and northeast SD. Some enhancement of this swath or band will be possible closer to midday through the afternoon with moderate snowfall occurring for a relatively short period of time during the afternoon. This will help push snowfall totals up to around an inch with best probabilities of seeing this occur from parts of central/north central SD southeast into the James Valley. Our far southern/southwest zones and far northeast zones will see less. BUFKIT profiles suggest there will be some dry air in the low levels to overcome initially through the morning, so it make take some time for snow to develop, especially in those southwest and northeast areas of our forecast area. Winds won't be much of a factor in conditions today so not expecting much in the way of blowing snow and associated reduce visibilities. This will change though heading into Wednesday.

After a short lived break from the precip tonight, the next clipper will be on our doorstep tomorrow morning. Guidance progs this system will track in a southeast fashion but farther north than today's disturbance. A more potent upper trough will slide southeast out of southern Canada into ND Wednesday morning pushing a sfc low pressure system into central ND and into the eastern Dakotas and western MN through the course of the daytime hours. Moisture values will be more limited with this system compared to today's but still expecting up to an inch in some areas, especially across the Sisseton Hills region. The more notable aspect of this system will be the wind it generates. The fropa is progged to slice through the CWA during the early to mid morning hours across central SD to late morning and midday across northeast SD and west central MN. Increasing northwest winds behind this boundary accompanying the snowfall and the already fallen fresh snow on the ground from today's system will potentially pose moderate impacts to localized significant impacts for parts of the CWA. How the exact impacts materialize will depend on the strength of the winds and how blowable the available snow on the ground is. Most models suggest gusts will range between 40-50 mph with highest probabilities of seeing gusts on the high end of that range or a little higher across central SD. The more significant blowing snow impacts could set up between the James and Missouri Valleys where a higher amount of fresh snow from today's system will be available. The developing theme for Wednesday is that hazardous travel conditions will set up across parts of the forecast area but be highly dependent on how much snow falls today and where it falls plus where the more intense areas of snowfall set up tomorrow.

LONG TERM /WEDNESDAY EVENING THROUGH MONDAY/

Issued at 543 AM CST Tue Jan 20 2026

The main concern in the long term will be quite the arctic air mass moving in Thursday and remaining over the region through the weekend. Friday morning will be the coldest period with wind chills in the thirties to potentially forties below zero. Saturday morning wind chills will still range in the twenties and thirties below zero. Clusters are in agreement on the CWA in northwest flow aloft as quite the large mid level low will continue circling over the Hudson Bay/eastern Canadian Provinces and southward through the Great Lakes and northeastern US region for the end of the week/weekend. This portion of the overall elongated low will finally track eastward a bit before getting absorbed into this larger circulation that will move very slowly east through early next week. As this does, a large amplified ridge will move in over the western CONUS next Tuesday/Wednesday.

Its surface low will be over southern Ontario/Great Lakes region Wednesday night and its arctic cold front extending westward through Alberta. This back door cold front will plunge southward through Thursday morning with the impressive 1050mb high sinking southeastward behind it. To give an example, highs on Wednesday will be in the 20s to lower 30s and by Thursday, highs will only be in the single digits and teens. The coldest air (and of the season) will be over the region Friday morning through the day Friday as the high will be over the Northern Plains and still cold Saturday with the high just off to our east. To give another example 850/925mb temps at 12Z Friday will range from -33 to-24C, coldest over northeastern SD/western MN. This runs within the 1 percentile for 850mb temps per climo! Saturday morning temps will range from -16 to -24C at 850mb and -18 to-26C at 925mb. NAEFs indicates these temps run about 2 to almost 3 standard deviations below climo. So actual overall lows will range in the teens and twenties below zero Friday and Saturday morning with forecast wind chills in the twenties and thirties below zero, and potentially forties below zero Friday morning. So Cold Weather headlines will defiantly be needed. Friday's highs, with the exception of south central SD, will not even reach zero and stay in the single digits and teens below zero. As the high shifts further away "warmer air" will filter in west to east across the CWA with temps warming gradually each day Saturday and onward with highs by Monday in the teens to the lower 30s, which will feel like summer!

Other than spotty 15% pops Friday/Saturday over south central SD, on the very northern edge of a strong system tracking over the southern CONUS, the overall forecast looks to remain dry through the weekend.

AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/

Issued at 543 AM CST Tue Jan 20 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are generally expected early in this forecast cycle before a clipper system delivers light snow to the area later this morning and persists until late this afternoon or early evening. MVFR cigs and vsbys will develop during this snowfall with the potential for IFR cigs/vsbys if snowfall becomes intense enough at any of the terminals. Winds will generally remain in check with southeasterly breezes through midday before turning more west to northwest later today into tonight. A few gusts between 15-20 knots will be possible at KPIR/KMBG tonight.

ABR WATCHES/WARNINGS/ADVISORIES

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