textproduct: Aberdeen

KEY MESSAGES

- High winds are still anticipated into the overnight hours. Peak wind gusts of 50 to 65 mph.

- Light snow showers tonight could result in brief periods of near blizzard conditions across the Sisseton hills and western Minnesota. Accumulations of an inch or two or less.

- Highs Friday and Saturday will be in the single digits to teens, coldest Sunday morning. Wind chill values Saturday and Sunday morning could be as low as -20 to -30 degrees.

- A few rounds of snow will be possible late this week into the weekend. Northeastern SD/west central MN has a 30-50% chance of 1" of snow Thursday into Friday morning. Another band of snow may impact mainly central SD over the weekend, but there is still a lot of uncertainty in the track and amounts.

UPDATE

Issued at 533 PM CST Tue Dec 9 2025

Aviation discussion updated below for the 00Z TAFs.

SHORT TERM /THIS EVENING THROUGH WEDNESDAY NIGHT/

Issued at 207 PM CST Tue Dec 9 2025

Mild air has migrated into the James valley and the southern Sisseton hills but has been stubborn in Roberts/Grant counties and western Minnesota where winds are still southeasterly. Rain is falling in the area however, and that should still effectively wet down the snowpack enough that future winds will not be able to tap into this. As for winds, only minor changes with latest set of guidance though timing is a little narrower.

Focus is on snow potential for the northeast this evening. BUFKIT profiles suggest initial moisture pivoting around the backside of the clipper lacks ice in the dendritic growth zone. This is manly through about 01 to 03Z depending on guidance, with ice available thereafter. CAMS bring bands/pockets of light snow down so its not the more traditional broad trowal, meaning winds plus the snow will not present widespread blizzard potential, it will be more hit and miss. Thus, went with a winter weather advisory for northeast South Dakota and western Minnesota. Again, existing snowpack will not be a factor in blowing/drifting, and conditions will rely on the coverage of snow shower activity. After 08-09Z the dendritic growth zone dries out again and by that point we are also experiencing a drop off in winds.

Ridge of high pressure moves overhead for late morning Wednesday, with the core of coldest air over the Red River valley into Minnesota. There will be a tight temperature gradient from southwest to northeast across the state. As the high moves off, we begin to see the gradient shift east in the form of a warm front. Profiles present another freezing rain scenario but this time mainly across the Missouri valley and just west of the James valley. The warm nose into the James valley isn't warm enough for melting resulting in snow this far east. NBM QPF is 1 to 2 tenths along the ND/SD state line in north central South Dakota with lower values to the south. A winter weather advisory has been issued in regards to this mixed precipitation scenario.

LONG TERM /THURSDAY THROUGH TUESDAY/

Issued at 207 PM CST Tue Dec 9 2025

The pattern of the Northern Plains remaining on the front side of the upper-level ridge over the western CONUS. With this setup, a couple of jet streaks will move over the area, providing enough divergence aloft to support precipitation Thursday through early Friday. Model soundings indicate that snow is the most likely precipitation type through the event, but there will be chances for rain and freezing rain as well. The latter precip types could occur with a de-saturation of the DGZ aloft during the event, which could transition from ice formation to liquid formation aloft depending on how cold temperatures at the top of the saturated layer remain. Latest ensemble medians have broad coverage of 0.10"-0.20" in liquid totals through Friday morning, with the highest totals over north central into northeastern South Dakota. This will translate to around 1"-2" across much of the forecast area, although varying snow to liquid ratios (~10:1 over north central South Dakota ranging to ~15:1 over northeastern South Dakota) may create a disparity between the highest liquid equivalent and highest snowfall locations. Latest probability of at least two inches peaks over northeastern South Dakota, ranging from 30 to 50 percent.

With this setup, a strong blast of cold air is expected to move into the region Friday into Saturday. 850mb temperatures by Saturday morning are expected to be in the teens below 0 Celsius, which is below the 10th percentile for this time of year. The presence of this cold air will lead to overnight lows at the surface below zero Fahrenheit Friday and Saturday mornings. At these temperatures, wind chills are expected to reach -20 degrees Fahrenheit in most of north central and northeastern South Dakota, and potentially even approach the Cold Weather Advisory Criteria of the northern counties of -30 degrees Fahrenheit. Friday morning is of particular concern, because while temperatures are slightly warmer than Saturday morning, northwesterly winds of 20-25 miles per hour gusting to 35 overnight will counteract that difference. The latest long-range ensemble guidance put the probability of hitting -30 degrees Fahrenheit for the minimum overnight wind chill in northeastern South Dakota at 20- 40% on Friday morning, easing up to around 10-20% Saturday morning.

Yet another round of snow may impact the region this weekend, this time being more banded with a swath of heavier precipitation totals. There is still a lot of uncertainty remaining, but it is worth noting that forecast snow totals have jumped up over the latest forecast cycle. The latest NBM currently puts a band of 50% probability to see 2" of snowfall accumulations, with a band of 20- 30% chance for up to 4".

AVIATION /00Z TAFS THROUGH 00Z THURSDAY/

Issued at 533 PM CST Tue Dec 9 2025

Terminals KABR,KATY,KPIR,KMBG

MVFR CIGs will overspread the region from the north this evening, with some question as whether or not the western extent reaches KPIR/KMBG. Areas of -SN/SN are also expected to spread southward across KATY/KABR region later tonight, with reductions in VSBY possible. Used PROB30 to handle this for the time being until confidence increases. Strong northwest surface winds gusting from 45 to 50 knots expected during the first part of the TAF period before slowly diminishing after 06Z. Low-level wind shear will also be a concern initially for the start of the TAF period and have inserted mention of this.

ABR WATCHES/WARNINGS/ADVISORIES

SD...High Wind Warning until 6 AM CST Wednesday for SDZ006>008-011- 018.

Winter Weather Advisory until 3 AM CST Wednesday for SDZ007-008- 011.

High Wind Warning until 3 AM CST /2 AM MST/ Wednesday for SDZ003>005-009-010-015>017-033>037-045-048-051.

Winter Weather Advisory from 6 PM CST /5 PM MST/ Wednesday to noon CST /11 AM MST/ Thursday for SDZ003-004-009-010- 015>017-033>037-051.

High Wind Warning until 6 AM CST Wednesday for SDZ019>023.

Winter Weather Advisory from 9 PM this evening to 3 AM CST Wednesday for SDZ020>023.

MN...High Wind Warning until 6 AM CST Wednesday for MNZ039-046.

Winter Weather Advisory until 3 AM CST Wednesday for MNZ039-046.