textproduct: Aberdeen

KEY MESSAGES

- Snow will return Friday into Saturday. Currently, there is a 30-80 percent chance of receiving more than 3 inches of snow throughout central and northeastern SD, and a 30-70 percent chance of receiving more than 5 inches of snow across central SD with this upcoming snow event.

- Below normal temperatures will continue through the beginning of December. Below zero wind chills area possible over northern SD each morning Thursday through Sunday. Wind chills will fall into the teens to near 20 below zero Sunday, Monday and Tuesday mornings.

UPDATE

Issued at 514 AM CST Thu Nov 27 2025

Updated for the 12z Aviation Discussion below.

SHORT TERM /TODAY THROUGH FRIDAY AFTERNOON/

Issued at 423 AM CST Thu Nov 27 2025

As of 10z, low clouds and fog have move in over north central and northeastern SD. These low clouds and fog are causing localized areas of lower visibilities at times. The fog should dissipate this morning after the sun rises. An elongated high surface pressure has moved in over central and northeastern SD today, which will help to keep precipitation out and winds light. Temperatures will be 5-15 degrees colder normal for the holiday and Friday. High temperatures through Friday will be in the low 30s over south central SD and in the upper teens to 20s over northern SD and west central MN, with low temperatures in the teens to single digits. Wind chills will get down to the single digits and the single digits below zero tonight.

Friday, the upper-levels have a small/weak ridge moving over SD. In the mid- to low- levels under the ridge, a line of WAA pushes into central SD Friday morning. This line of WAA has frontogenesis along it that will help to develop a band of snow starting Friday morning. This band of snow will move into central SD Friday morning before slowly spreading to the east. There looks to be an strong initial surge of snow Friday over an areas between the Missouri River and James River. While models have place the highest rates Friday over Walworth/Edmunds county to the southeast over Hyde/Hand county over the past couple of runs, the highest snow totals could move due to where the band and frontogenesis sets up on Friday.

Snowfall amounts during the day Friday until Friday night shows a line with 30-80% chance for 3 inches or more from Mobridge to Miller with the highest chances. The lower chances (around 20-40%) at the edges of the line which includes Aberdeen to Clark on the eastern edge of the line and Pierre on the western edge. There is then a 30- 60% chance for greater than 5 inches of snow until Friday evening over southern Edmunds, Faulk, Hyde, and Hand counties as well as slightly lower chances on the western edge of Spink county. These chances increase as the overnight into Saturday time periods are included (see long-term discussion below). Winds pick up slightly Friday under the band, with gusts in the afternoon forecast to get up to 25-30mph, strongest to the southwest of the highest snow rates. These winds could lead to localized areas of patchy blowing snow in central SD Friday. The snowfall probabilities Friday and the ones on Saturday (more on this below) in combination with the fact that this event will be happening the day after Thanksgiving and many will probably be trying to travel, have lead to a winter storm watch being issued for a few counties with the highest snow totals. This watch area will most likely need to be updated as snow totals continue to shift locations and amounts.

LONG TERM /FRIDAY EVENING THROUGH WEDNESDAY/

Issued at 423 AM CST Thu Nov 27 2025

The main focus in the long term will be the ongoing snow event at the start period along with much below normal temperatures persisting through early December. Beginning 00Z on Saturday, a fairly potent looking 500mb trough is progged to be tracking eastward out of the Central Rockies into portions of the Central/Southern Plains. This upper wave will have induced a 1006mb Colorado low pressure system that is progged to track eastward into KS/OK with an inverted trough extending northward into NE and SD. During the daytime hours on Saturday, guidance takes this storm system northeastward toward St. Louis by Saturday night and eventually into the central and eastern Great Lakes the latter half of the upcoming weekend.

A northwest to southeast oriented band of snow will already be underway by the beginning of this period. There remains decent agreement among guidance in tracking this snow east to southeast during the day on Saturday with a gradual tapering off trend expected from northwest to southeast Saturday afternoon into the early evening. Easterly upslope flow Friday night into early Saturday will turn more northeast to north on Saturday as the inverted sfc trough passes through and exits our area to the east. The WAA/frontogenesis induced heavier or more steady snowfall still looks to occur during the overnight hours through about daybreak-mid morning Saturday. Lighter snowfall will generally take hold the remainder of the day before tapering off and ending by late afternoon or early evening. There remains not much change in the overall QPF/snowfall probabilities footprint across the forecast area. Given the dynamics involved in this wave, parts of our area could be in line to pick up at least a quarter of an inch of liquid precip. Highest probabilities of seeing more than this amount range from 50- 80 percent on a line from the Mobridge to Faulkton to Huron. Lower probs(20-50 percent) surround this area on both the north and east side(Aberdeen/Watertown areas) and the the west and south side(Pierre/I-90 corridor areas). Snowfall probabilities of seeing more than 4 inches continue to highlight zones between the Missouri and James Valleys or roughly from Edmunds County south through Hyde/Hand and east through Spink and Clark Counties. These areas sit at about a 70-90 percent chance of seeing more than 4 inches and about a 50-70 percent chance of seeing more than 6 inches. As mentioned earlier, a Winter Storm Watch has been issued for these locations from mid morning Friday through late Saturday afternoon. There will be some wind to accompany this storm system but nothing comparable to our last clipper like system on Tuesday. Gusty winds up to 30 mph will be possible Saturday afternoon across south central SD. Some blowing and drifting along with reduced visibility(especially during snowfall) will be possible through late Saturday afternoon/early evening, but improvement expected after the snowfall ends and winds diminish Saturday night.

A 1040mb sfc high pressure system is then set to build into the region Saturday night into Sunday sending southward a reinforcing shot of arctic air into our area that will persist into early next week. This sfc high is then expected to shift east by Tuesday which will promote a more southerly low level flow to take over only to be followed by another frontal boundary passage that may deliver some precipitation to parts of the area at the end of this period. Daytime temperatures in the teens and low 20s on Saturday will take a nose dive Saturday night falling into the single digits above and below zero. A very cold end to the holiday weekend is expected with daytime highs on Sunday only reaching the upper single digits above zero to mid teens. Throwing in a little bit of wind(5-15 mph) will produce wind chill values into the 15-20 below range. These much below normal temperatures will prevail through the middle of next week, even with a slow and slight warming trend expected. Daytime temperatures in the 20s to low 30s may be possible by the end of this period.

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/

Issued at 515 AM CST Thu Nov 27 2025

Terminals KABR,KATY,KPIR,KMBG

Low clouds and visibilities will continue to cause MVFR/IFR conditions this morning over KABR, KMBG, and KATY. The low clouds will continue to cause IFR/MVFR conditions through most of the day today. KPIR is the exception as it has and will continue to have VFR conditions though the day.

ABR WATCHES/WARNINGS/ADVISORIES

SD...Winter Storm Watch from Friday morning through Saturday afternoon for SDZ010-017>019-036-037.

MN...None.