textproduct: Aberdeen

KEY MESSAGES

- Snow returns Saturday. 1 to 4 inches of accumulation is expected, with highest amounts south of Highway 212 in east central SD.

- There will be periodic lower chances for precipitation (20-40%) through early next week, as more weak weather systems have the potential to move through the region.

DISCUSSION

Issued at 103 PM CST Fri Dec 5 2025

The pattern will remain active through the middle to end of the upcoming week. The region will mostly stay in an upper trough but will continue to have numerous shortwaves rotating through the upper- level flow. These shortwaves will bring periods of light snow and potentially mixed precipitation through next Thursday.

Most of today's precipitation has exited the region, however there is still a mix of light snow and freezing drizzle in west central MN early this afternoon. Colder air has also backdoored into the northeast, causing temperatures to fall about 5 degrees since this morning. Surface low moves through NE on Saturday. This combined with a shortwave over SD will produce some light snow starting early in the morning across central SD and moving east through the day. A Winter Weather Advisory has been issued for portions of east central SD where higher QPF has pushed farther north in latest model runs. Generally expecting 2-4 inches south of HWY 212, with lower amounts farther north and west. Snow showers may linger well into the evening on the backside of the surface low.

Arctic high pressure builds into eastern SD Saturday night into Sunday when highs may only be in the single digits east of the James Valley. Return flow behind the high as well as an upper ridge building east into the Plains will see temperatures rebound into Monday as highs climb into the 40s in central SD. The warmer air Sunday night along with a passing shortwave could result in some additional light snow. On Tuesday, low pressure remains to the north with main impacts across ND and MN. Will need to keep an eye on this one as any southerly drift in the track of the low could significantly change expectations. Wednesday night into Thursday has the potential for more warm air advection banding with the low pressure heading over SD and NE.

From Saturday evening through the end of the period, the over- arching flow pattern theme remains "positive PNA". Northwest flow is still lining up transient clipper-like shortwaves over the region, each one separated from the next by roughly 24 hours.

With the active pattern of low pressure systems working through, the low level thermal advection pattern will be pretty busy. Weak low level CAA is happening Saturday night into Sunday morning, but low level WAA is expected to kick in by late in the day Sunday and persist into Monday. Warm air is forecast to stick around Monday night into Tuesday before the next system's strong cold frontal passage knocks temperatures back down to near to below normal for the middle of next week.

The probabilities of seeing a 0.10in or more of water equivalent in any given 24 hour period in the out periods is low (less than 10 percent). Likewise, the chances of seeing 0.01in or more of freezing rain/ice accumulation or 3 inches or more of snow are low. That being said, the clipper system moving through North Dakota into Minnesota Tuesday/Wednesday will need to be watched closely for any shifts further south in track/placement, as this system holds the chance of producing headline-able conditions. But for now, model output/ensembles are still maintaining that the bulk of this system will track through the region north of this CWA.

Looking a little bit more closely at the wind potential Tuesday/Wednesday, it appears that a corridor of fairly strong winds (off the surface) will be overspreading the CWA while it's within the warm sector of the clipper system. Current model progs suggest that it's not until at or after 21Z Tuesday that strong winds aloft will be able to be mixed down to the ground, as that is roughly what time the system's cold frontal passage is slated to begin sweeping through the CWA, first across north central South Dakota, but then quickly following through central and northeast South Dakota and west central Minnesota, especially at or after 00Z Wednesday when strong low level CAA, pressure rises and winds just a half kilometer off the ground will be working in tandem to present a strong wind concern. Not too confident about a blowing snow concern, though, if the CWA has been at or above the freezing mark for nearly 48 hours. Thinking there may not be much blowable snow left after warm boundary layer conditions like that.

AVIATION /18Z TAFS THROUGH 18Z SATURDAY/

Issued at 1115 AM CST Fri Dec 5 2025

Terminals KABR,KATY,KPIR,KMBG

IFR/MVFR cigs will prevail through the next 24 hours. Any lingering precip should taper off in the next hour. However, another round of snow will develop early Sat morning.

ABR WATCHES/WARNINGS/ADVISORIES

SD...Winter Weather Advisory from 9 AM to 6 PM CST Saturday for SDZ018-019-022-023.

MN...None.