textproduct: Aberdeen

KEY MESSAGES

- Another round of light accumulating snow moves through the area today with accumulations generally up to 1 inch possible.

- Strong northwest winds develop this morning and persist through the daytime hours. Gusts will range between 45-75 mph with the strongest winds expected across central South Dakota. Blowing snow and reduced visibilities are expected, especially in falling snow. A Winter Weather Advisory remains in effect.

- 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. High temperatures for Friday will stay below zero with wind chills in the twenties and thirties below zero. An Extreme Cold Watch is in effect for Thursday evening through Friday afternoon.

UPDATE

Issued at 1028 AM CST Wed Jan 21 2026

Very strong winds across central SD this morning, gusting between 60 and 80 mph. Had earlier issued a High Wind Warning until 18Z as by that time, winds should hopefully start subsiding to where gusts are around 55 mph or below. Otherwise, watching light to moderate snowfall move across the region and the bulk of it should be exiting over the next hour or two. Blowing snow and reduced visibility where there is falling snow, although even when it's not snowing, will still see areas of blowing/drifting snow. Made some adjustments to PoPs to better match radar trends and also increased wind gusts across the region, especially through the morning hours.

SHORT TERM /TODAY THROUGH THURSDAY AFTERNOON/

Issued at 500 AM CST Wed Jan 21 2026

The main focus in this period will be on today's clipper system that will deliver another round of light snow and strong winds to the forecast area. The beginnings of this system are already showing up on sat/rad with thicker cloud cover and light snow to our northwest in western ND extending southeast into north central SD. For the moment early this morning, our area has been in and out of pockets of stratus/stratocu drifting southeast along with some areas of flurries or snow showers. An upper trough axis will quickly move southeast through the morning and midday hours. This will accelerate a sfc low pressure system quickly into eastern ND by mid morning and then into central MN during the first half of the afternoon. Timing of the associated fropa slices through our forecast area during the first half of the morning across our western zones and through our eastern zones by late morning/midday. Light snowfall will spread from north central sections of SD into central/eastern zones by mid to late morning. Total accumulations will be up to 1 inch generally north and east of a McIntosh to Gettysburg to Miller line. Some upslope enhancement on the Prairie Coteau may push values to between 1 and 2 inches. The second part to this system will be increasing northwest winds.

A 100-120 knot jet streak is progged to push across western SD and our western zones today. Efficient mixing will push the strongest gusts across the western half of our forecast area, basically west of the James Valley. Our western zones(central SD) could see gusts range between 45-50 knots between about mid morning through mid afternoon. BUFKIT profiles at Pierre and Mobridge indicate gusts at the top of the mixed layer range between 50-60 knots with average speeds within the layer ranging between 35-45 knots between mid morning and midday. However, guidance progs 8-10 mb 3 hour pressure rises mid/late morning with the fropa and incoming sfc high across central SD. The one caveat is that although there will be some cold air advection starting to take place during that time across our west, it's not substantially strong. Taking all this into account, the feeling is wind gusts will approach or touch High Wind Warning crit in a few spots for a short period of time, but mostly remain at Wind Advisory levels(>45 mph)on average through the day. Have left the Wind Advisory in place and will just have to monitor obs and make changes if warranted. Regardless if gusts get to warning levels or not, areas of blowing snow and reduced visibilities are likely, especially in areas that have a fresh snow cover or during the falling snow. However, new snowfall across parts of central SD today could be limited lessening impacts to visibility. It may all depend on the characteristic of the fresh snow on the ground or lack thereof that will drive the blowing snow/low visibility hazards. For locales that have had fresh snow or falling snow(north central/northeast SD and west central MN), the strong winds will pose hazardous travel conditions through this afternoon. The worst cases will be found in open country and therefore will continue with the Winter Weather Advisory.

Light snowfall will taper off during the afternoon hours with perhaps some flurries hanging on into the late afternoon or early evening. Winds will begin to diminish after sunset tonight with more tranquil conditions developing. Temperatures will plummet overnight into the single digits above and below zero but any residual cloud cover will help. Thursday will be quite chilly but not as cold as what's to come beyond this period. Guidance progs the arctic boundary will descend south into the area during the mid morning to mid afternoon time frame on Thursday. This will mark the leading edge of a really cold air mass that will begin to move into our area during the afternoon. Wouldn't be surprised to see temperatures fall below zero across our northern/northeastern zones Thursday afternoon.

LONG TERM /THURSDAY EVENING THROUGH TUESDAY/

Issued at 500 AM CST Wed Jan 21 2026

The main highlight in the long term will be the blast of arctic air moving in over the region for the end of the week continuing through the weekend. The coldest period, and therefore the dangerously cold wind chills, will be Friday morning through Saturday morning. Models are consistent on this impressive 1052mb high that will slide in from the northwest, with the CWA on the southeastern side of this elongated high at 00Z Friday. By 12Z Friday the center the high will be over ~northwestern ND/Alberta. It will continue to track southeast and then more easterly as the high will then centered over the Upper Midwest by 12Z Saturday. By this time the Northern Plains will be in between this high to our east and an area of low pressure to our west over Montana and northwestward. Just to give you an idea on how "high" this high is, the mean MSLP and climatological percentile at 12Z Friday runs from 99.5% to all time max per ECMWF/GEFS! This is about 3 standard deviations above climo for MSLP per NAEFS and GEFS M-Climate! The return interval, meaning the frequency of occurrence in the Jan 13-Feb03 1985-2012 timeframe is both outside the 12Z CFSR climate and outside CFSR climate for all time periods for NAEFS!

This arctic high will bring in quite the cold temperatures and coldest of the winter season thus far (hopefully this will be it). 850mb temps between 00Z Friday-12Z Saturday runs about 2 to 3 standard deviations below climo per NAEFS with a return interval of once every 5-10 years. The coldest period will be Friday morning as by 06Z, 850mb temps (per grand ensemble mean) will run between -35 to -22C, coldest over northeastern SD. This is within the 0 to 3rd percentile range per climo, lowest over over northeastern SD. By 12Z Friday, temps are still running in the 20s to 30s below zero range over the CWA at 850mb. 925mb temps will also run in the twenty to thirties below zero. So forecast surface lows Friday morning are forecast in the teens and twenties below zero. Looking at the NBM 5th percentile (for a worst case scenario) and temps could potentially be -25 to almost -30F over the CWA if we have stronger than forecast colder air already along with strong radiational cooling and overall clear skies (besides our extreme southern CWA) as winds are forecast to become light. Forecast wind chills range from 30 below zero to potentially 45 below, coldest over northeastern SD and especially over the Coteau. Due to this, an Extreme Cold Watch remains in effect for locations east of the Missouri River. Even during the day on Friday, 925mb temps will range in the twenties below zero with daytime highs mainly in the single digits to teens below zero. Prob of temps above zero is 15- 30%, highest over our extreme southern CWA. Wind chills even by the afternoon will still be in the twenties to potentially 30 below zero, coldest over the Coteau. EC EFI for both max and min temps Friday morning/Friday day shows values of -0.9 to -0.99 and shift of tails of zero! Even though its going to be cold, we will not be near record cold temps at this point in time.

Saturday morning, it will still be cold but "warmer" than Friday morning with 12Z temps at both 850/925mb in the twenties below zero, which still runs in the bottom 3rd to 5th percentile per climo as we will be on the western edge of this high by 12Z Saturday. So early morning lows are only a couple of degrees warmer at any one location, but still running in the teens and twenties below zero and wind chills in the twenties to about 35 below zero. So this may only warrant a Cold Weather Advisory. Highs will range in the single digits below zero to about the lower to mid teens, warmest south central SD. By Sunday morning, temps will range in the single digits to teens below zero with daytime highs around zero to the mid teens.

By early next week the large deep upper troughing pattern we have been dealing with will finally shift off to the east a bit as an amplified ridge will build over the western CONUS and remain over this area through at least the middle of next week with winds aloft in northwest flow. The western CWA will see more of an influence from this ridge while the eastern CWA will continue to be on the backside of this upper trough. Anyways, temps will gradually increase through the midweek with highs by Tuesday in the teens to lower 30s, warmest south central SD. Precip wise, our only real chance (15-20%) is Friday evening/early Saturday for light snow over portions of south central SD.

AVIATION /12Z TAFS THROUGH 12Z THURSDAY/

Issued at 557 AM CST Wed Jan 21 2026

Terminals KABR,KATY,KPIR,KMBG

Deteriorating conditions are expected at all terminals this morning as light snow moves through the area which will be followed by increasing northwest winds. VFR conditions initially this morning at KABR/KATY will quickly turn to MVFR/IFR cigs and vsbys as light snow and blowing snow develop. Expect these conditions to persist into the afternoon but improve once the light snow ends. MVFR cigs/vsbys will be possible at KPIR/KMBG through at least midday before improving during the afternoon after the light snow ends. Blowing snow will still be possible through the afternoon at KPIR/KMBG. As a strong upper jet mixes down this morning, a few hours of low level wind shear will be possible at KATY/KPIR/KMBG TAF sites.

ABR WATCHES/WARNINGS/ADVISORIES

SD...Winter Weather Advisory until 6 PM CST /5 PM MST/ this evening for SDZ003>011-015>023-033>037-051.

Extreme Cold Watch from Thursday evening through Friday afternoon for SDZ003>011-015>023-034-036-037.

High Wind Warning until noon CST /11 AM MST/ today for SDZ003- 004-009-015-016-033>035-045-048.

Cold Weather Advisory from 6 PM CST /5 PM MST/ Thursday to 3 PM CST /2 PM MST/ Friday for SDZ033-035-045-048-051.

Wind Advisory until 6 PM CST this evening for SDZ045-048.

MN...Winter Weather Advisory until 6 PM CST this evening for MNZ039- 046.

Extreme Cold Watch from Thursday evening through Friday afternoon for MNZ039-046.