textproduct: Aberdeen

KEY MESSAGES

- Fog potential continues tonight, mainly in and east of the James River valley, where visibility may be reduced to around one- quarter mile or less.

- Patches of freezing drizzle or very light freezing rain will affect northeast SD and west central MN this afternoon possibly into early this evening before ending. This could lead to a few slick spots on roadways.

- Light precipitation (mostly in the form of rain; less than 10 percent chance of freezing rain/0.01in of ice accumulation) chances are starting to show up with a little bit more clarity for late Monday afternoon through early Wednesday. Little in the way of measurable precipitation expected.

- Temperatures for much of this week will be anywhere from 5 to 20 degrees above normal.

UPDATE

Issued at 1120 PM CST Sun Jan 4 2026

Just a quick update to expand the dense fog advisory. See below for the 06Z Aviation discussion.

SHORT TERM /THIS EVENING THROUGH MONDAY NIGHT/

Issued at 211 PM CST Sun Jan 4 2026

At 2 PM CST, there is a mix of sun and clouds over the CWA. Temperatures are in the upper 20s to mid 40s, and south winds ranging from 10 to 25 mph with some occasionally higher gusts are switching around and becoming northwest, in the wake of this surface low passage, around 10 to 20 mph with gusts up to 30 mph. There continues to be a swath of fairly dense fog positioned over several counties between the James and Missouri River valleys, too. The potential for freezing drizzle or freezing sprinkles is moving east now, heading out of north central South Dakota and through northeast South Dakota (freezing misting at KABR). Headlines for fog and freezing drizzle continue.

With the surface low that is attached to the mid-level shortwave overhead forecast to move east of the CWA by 00Z this evening, a rather ill-defined surface pressure pattern (rather weak bubble surface high pressure) sets up, with winds going light overnight. Still not a sufficient push of low level dry air advection tonight, at least not enough to support the potential formation of more fog and low clouds over the James River valley and points east. Some of the fog could become dense, again, overnight.

When the next in a rapid succession of transient mid-level shortwaves out west begins to move through the region on Monday, there could be a brief window where enough saturation happens to support sprinkles/very light rainfall potential from ~23Z Monday through 12Z Tuesday across northeast South Dakota into west central Minnesota. After 06Z Tuesday, additional UVV's working in from Wyoming/Montana, could be bringing light precipitation into north central South Dakota before shifting it off to the east through Tuesday morning. P-type is liquid precipitation. It's all going to boil down to surface temperature, as to whether or not p-type is called plain rain or freezing rain. The probability of 0.01in or more of precipitation within the 24 hour period from 6 PM CST Monday to 6 PM CST Tuesday over the CWA ranges from 15-25 percent over central/north central South Dakota to 25-40 percent over northeast South Dakota into west central Minnesota (a slight uptick in probabilities compared to 24 hours ago).

Overall, the period waffles back and forth between moderate low level WAA and weak CAA. Suffice it to say, above normal warmth is expected to persist through Monday night.

LONG TERM /TUESDAY THROUGH SUNDAY/

Issued at 211 PM CST Sun Jan 4 2026

When the period opens, zonal flow aloft and a couple of ongoing transient shortwave passages means that if there aren't any now, there will probably begin to appear some low PoPs Tuesday and perhaps into Wednesday. Then, the flow pattern is forecast to begin buckling again, into a positive PNA pattern, once an upper level longwave trof moves from the west coast, passed this CWA, to the east coast later this week into next weekend.

Clusters analysis does not show much in the way of qpf over this CWA with the Friday/Saturday upper level longwave trofpa, so maintaining "status-quo" of NBM's 15 to 20 PoPs and no qpf for said system. There is a decent cold front still progged for Wednesday night over this CWA, which will knock temperatures down from 10 to 20 degrees above normal (Tuesday/Wednesday) to something more in line with "near normal" to perhaps up to 5 degrees above normal (Thursday through Sunday).

AVIATION /06Z TAFS THROUGH 06Z TUESDAY/

Issued at 1120 PM CST Sun Jan 4 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions with light/variable winds for KPIR/KMBG. Currently VFR at KABR, but expected fog for later tonight. Fog is already at KATY and will persist through the mid-morning.

ABR WATCHES/WARNINGS/ADVISORIES

SD...Dense Fog Advisory until 9 AM CST Monday for SDZ007-008-011- 019>023.

MN...None.