textproduct: Sioux Falls

KEY MESSAGES

- A brief influx of arctic air will lead to cold temperatures and even colder wind chills (as low as -25 to -30F) tonight into Sunday morning.

- Quieter conditions with mild temperatures return next week, though fresh snowpack may impact how quickly temperatures warm early in the week.

- Wednesday night into Thursday will be the next system with the potential for impacts across the area. More of a wind threat than precipitation threat but if any snow can fall with the cold surge, blowing snow will be possible.

DISCUSSION

Issued at 159 PM CST Sat Dec 13 2025

Arctic high pressure builds south tonight which will allow for lighter winds over fresh snowpack. This should lead to lows mainly from -10 to -20. When coupled with the light winds, wind chill values will average about -15 to -30, resulting in a cold weather advisory for parts of the area.

High pressure quickly shifts east on Sunday which will bring a bit warmer temperatures, but much breezier conditions. With the fresh snow cover it is likely we will not mix down as strong of winds as possible, but suspect gusts will be in the 20 to 30 mph range. With these stronger winds and the fluffy snowpack, expect some patchy blowing and drifting during the day into the evening on Sunday.

Milder air builds into the area Monday and while much of the warmth will not be realized at the surface due to the recent fresh snow cover, temperatures will still climb back to around normal. Areas west of the James River with less snow cover will see temperatures climb into the low to mid 40s.

A fairly strong upper level jet moves through the area on Tuesday but will be fighting plenty of dry air so at this time precipitation looks very unlikely. Mid level clouds and saturation in the DGZ look likely, but the DGZ is also very elevated and will not be able to fight through the lower level dry air. Ahead of this wave on Tuesday much warmer air will surge into the area and highs from the mid 30s in northwest IA to around 50 over snow free areas is expected.

Shortwave ridging on Wednesday ahead of a very strong wave expected Thursday will bring another mild day to the area. Assuming snow cover has diminished with the milder temperatures Monday and Tuesday, widespread 40s are expected with highs in the 50s west of the James River.

Strong low pressure moves into the area on Thursday and is expected to deepen near the ND/Canadian border, then drift east with a strong wave expected to dive southeast behind this deepening low pressure. The west/northwest winds ahead of this Thursday will potentially see gusts around 50 mph, then the strong wave on the backside will turn winds more northerly with a potentially very strong and compact push of cold air and a continued threat for 50+ mph winds. Plenty of warming ahead of this cold surge that any blowing snow will be relegated to anything that can get squeezed out of the cold surge as low and mid level temperatures crash into the DGZ. Not out of the question for a short duration, 3-9 hour, low visibility situation with snow and blowing snow. But again, any existing snowpack will likely not be blowable after multiple mild days.

Some disagreement comes in for Friday and Saturday, so confidence a little lower. Models leaning slightly towards a warm surge Friday, then colder air filtering in behind for the weekend.

AVIATION /00Z TAFS THROUGH 00Z MONDAY/

Issued at 524 PM CST Sat Dec 13 2025

Conditions remain vastly VFR early this evening as there remains a little MVFR stratus just barely touching K9V9. Clear skies and light and variable winds will persist for the evening and overnight hours. Winds will pick up out of the south tomorrow and strengthen with gusts up to 20-30 knots. The breezy winds may lead to patchy blowing snow as well to finish out the TAF period.

FSD WATCHES/WARNINGS/ADVISORIES

SD...Cold Weather Advisory until 10 AM CST Sunday for SDZ038>040- 053>056-059>062-065>067. MN...Cold Weather Advisory until 10 AM CST Sunday for MNZ071-072- 080-081-089-090-097-098. IA...Cold Weather Advisory until 10 AM CST Sunday for IAZ001>003- 012>014-021-022-032. NE...None.