textproduct: Aberdeen

KEY MESSAGES

- Breezy southerly winds will lead to subzero wind chills through midday. An area of enhanced southwest winds across the Sisseton Hills today could lead to some patchy blowing snow.

- A quick moving disturbance will push through the region the latter half of Tuesday into early Wednesday and kick off some light precipitation in the form of snow and a wintry mix.

- Very cold air across the region Wednesday night, with lows in the single digits below and teens below zero. Wind chills may reach 25 below to 30 below zero in the James River valley.

- Show chances (20-30%) return Friday night/Saturday as another clipper system potentially moves through.

UPDATE

Issued at 539 AM CST Mon Dec 1 2025

The aviation discussion has been updated for the 12Z TAFS.

SHORT TERM /TODAY THROUGH TUESDAY AFTERNOON/

Issued at 443 AM CST Mon Dec 1 2025

A mixture of clear skies and low stratus early this morning across the forecast area. Southerly low level flow has led to low stratus streaming northward and downwind of Lake Oahe and nearby sections of central SD. There could perhaps be a few flurries associated with this but haven't seen any evidence yet from sfc obs and SDDOT webcams. Seems as if winds remain stirred enough to prevent any fog development, but something to watch the next few hours. Other low stratus is shifting northeast across northeast SD and west central MN.

Sfc high pressure ridge will continue drifting farther away from our forecast area early this morning which will promote an increase in southerly breezes through midday. As a result, subzero wind chills will still remain present. Hi-res guidance does point to gusty southwest winds developing across the Sisseton Hills and downslope area by mid morning through late afternoon or early evening. Did increase winds speeds and gusts in that area but not enough to kick off much for blowing snow. It'll be something the incoming day shift will have to keep an eye on for further adjustments to the forecast if needed. An upper trough axis will swing southeastward across the region today. A few flurries may be possible as far north as the I- 90 corridor in our far southern zones in south central SD through the early morning hours and perhaps beyond daybreak but mostly dry conditions will be the rule across most of the CWA today. Temperatures will remain rather chilly, especially across areas that have a deeper snowpack. Teens for highs will be prevalent from portions of central and north central SD into northeast SD and west central MN. Some low level WAA will aid in afternoon readings reaching the low to mid 20s south and west of the Pierre area.

A warm front approaches the region tonight into Tuesday morning. Clear to partly cloudy skies early on through the evening will allow temperature readings to fall quickly into the single digits above and below zero. HREF probs for temperatures colder than 0F range from 40-80 percent across north central and northeast SD into west central MN. Clouds increase from west to east tonight into early Tuesday. Depending on how quickly they increase will play a factor in how quickly temperatures fall tonight. We might see readings stabilize or increase a bit closer to daybreak Tuesday. That warm front is all part of the next disturbance that will shift east into the Dakotas during the day. There will be enough moisture for this clipper like system to work with to produce a round of light snow and perhaps a rain/snow/sleet mixture closer to midday and afternoon hours. At this point, QPF values remain light, so not anticipating anything too heavy, but a light coating of snow will be possible for some areas by late in the afternoon. How quickly that warm front moves through our area will dictate how warm temperatures get. Central SD has a shot at readings in the low to mid 30s. Some question remains though farther east and in areas that have the deepest snowpack. Nonetheless, at least highs in the 20s look probable.

LONG TERM /TUESDAY EVENING THROUGH SUNDAY/

Issued at 443 AM CST Mon Dec 1 2025

Tuesday night will still be dealing with the passing low pressure and associated warm front/cold front passages and resultant snow/mixed precip chances. Continued the trend from the short term with increasing PoPs across the region. Grand Ensemble shows a large area of 40-70% chances for measurable precipitation in a 6-hr period ending at 06Z Wednesday. Highest chances show up on the Coteau region. Did raise PoPs slightly more into the 30-50% range across much of the CWA for Tuesday evening before chances decrease quite a bit beyond 06Z Wednesday. Cannot rule out light snow accumulations continuing into Tuesday evening, but Grand Ensemble showing only <20% chance of seeing anything more than a half inch. Thermal profiles/surface temperatures would support mixed precip across central SD, although rather light QPF generally less than a tenth (90th percentile) likely.

Cold front will also be moving through the region Tuesday night, with a surface high building into the day Wednesday. Much colder air with 925mb temps likely from -15C to -17C across the area during the day Wednesday. Current forecast highs are only in the teens. But it's Wednesday night when the heart of the cold air settles in as lows drop into the single digits below and teens below zero. Interesting to note current apparent T forecast is in the 25 below to 30 below range in the James River valley 06Z to 12Z Thursday.

GEFS/ENS/GEPS 6-hr mean MSLP and mean 6-hr precip shows another clipper system potentially sliding southeast across the High Plains/Northern Plains Friday night into Saturday, with inherited chances generally in the 20-30% range.

AVIATION /12Z TAFS THROUGH 12Z TUESDAY/

Issued at 539 AM CST Mon Dec 1 2025

Terminals KABR,KATY,KPIR,KMBG

VFR conditions looks to persist for the most part during this TAF cycle, with the exception of KMBG this morning. Southerly winds have produced low stratus downwind of Lake Oahe. IFR cigs/vsbys will be possible through about mid morning before transitioning to MVFR before becoming VFR perhaps closer to late morning or midday. Breezy conditions at times will be possible with strongest gusts of 20-25 knots at KATY.

ABR WATCHES/WARNINGS/ADVISORIES

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