textproduct: Sioux Falls

KEY MESSAGES

- A strong, compact wave brings the potential for brief, near whiteout conditions on Sunday with periodic snow chances and wind gusts up to 40 to 55 mph.

- Very cold Sunday night into Monday morning with wind chill values 15 to 25 below zero.

- Additional chances for snow are possible through next week. Details are uncertain as of now.

DISCUSSION

Issued at 237 PM CST Sat Jan 17 2026

Light snow and low level stratus continue to push off to the south and east this afternoon. Snow is just about done falling but remaining breezy northwest winds are continuing to result in patchy blowing snow. This is mostly in parts of southwest Minnesota that received the most snowfall yesterday. While winds continue to gust up to 30-35 mph, they will weaken through the rest of the afternoon hours. Winds will be much lighter for the evening hours, but the light winds will not last long. Warm air advection (WAA) will strengthen during the evening hours as a shortwave passes through the amplified flow aloft. This shot of WAA will bring renewed chances for snow with it overnight and also warm temperatures at the surface. Temperatures will remain below freezing, keeping the precipitation type as all snow. This warm advective snow will quickly race through the area during the overnight hours.

Winds will restrengthen on its heels by about to just after sunrise on Sunday. Gusts up to 40-55 mph is expected, strongest west of the James River. Additional snow showers are expected throughout the day on Sunday but these snow showers will be quite narrow. The falling snow combined with the strong winds will make for reduced visibility in the snow showers, resulting in the potential for near whiteout conditions. With some snow on the ground across the area, blowing snow is also expected outside of the snow showers as well, mainly across locations that received snow yesterday. The lowest visibility will reside in the snow showers themselves where visibility may drop to below a half a mile. While quite similar to yesterday, moisture does not look as impressive as compared to yesterday's set up. Thus, the coverage of snow showers will be a little less widespread than what we saw yesterday. Winds will also be strong but the strongest winds look to come during the morning hours on Sunday as mixing quickly increases as another cold front and associated shot of cold air advection (CAA) passes through the forecast area. The winds will be slowly weakening through the afternoon hours. Snow is not expected to be all that much, with amounts generally an inch or less. Isolated areas could see an inch or more where these narrow bands of snow persist over a longer period of time. Thus, have issued another Winter Weather Advisory for the entire forecast area. The Advisory in in effect from 3 am to 9 pm Sunday.

The snow showers will be ending across the area by the evening time frame. However, with continued breezy winds and temperatures falling to near 0F to the negative single digits overnight, cold wind chills are again on the table. Could see wind chills fall to around -15F to -25F overnight, coldest across parts of east central South Dakota, southwest Minnesota, and northwest Iowa. Cold Weather headlines may be needed if confidence increases in wind chills dropping below -25F.

Monday will be a cold day with high temperatures only warming to the single digits and teens. A few locations across south central South Dakota may crack 20F. Winds will remain marginally breezy, making for colder wind chills down to either side of 0F throughout the day.

Temperatures look to rebound for the middle of the week with highs remaining near seasonable in the teens, 20s, and 30s. Medium range guidance is in somewhat decent agreement in another shortwave trough passing through the area on Tuesday. The Euro and Canadian ensembles show high probabilities (60-90% chance) for precipitation amounts to exceed a mere hundredth of an inch. The GFS ensemble has the lowest probabilities with only about a 20% chance for exceeding the same amount. Due to remaining uncertainty, have stuck with NBM PoPs.

Medium range guidance shows increasing variance in the upper level pattern for the end of the week. There could be be more chances for snow but details are too uncertain at this time. Temperatures look cool back below average to end the week.

AVIATION /00Z TAFS THROUGH 00Z MONDAY/

Issued at 535 PM CST Sat Jan 17 2026

Still some lingering MVFR stratus across the area this evening, which may continue through the late evening. Otherwise, mainly VFR conditions prevail into the overnight. A round of snow is expected to move west to east over the area late tonight into Sunday morning, and have included mention at all three sites via PROB30 groups. Additional periods of snow showers are expected through the day tomorrow; however, narrow banding leads to lower confidence in temporal and spatial extent. Omitted mention from both KFSD and KSUX due to these issues. Any snow showers will lead to MVFR/IFR and possibly brief LIFR conditions.

Still seeing some stronger winds this evening with gusts around 25 knots. Expect winds to taper down into tonight and shift to southerly before switching back to the northwest Sunday morning. Some brief periods of LLWS (mainly directional shear) are expected as winds shift. With increasing winds as direction shifts, main shear concern is directional, although speed shear will be more of a factor if gusts are slower to increase. Winds increase through the morning with gusts around 40 to 50 knots Sunday - highest in south central SD. Strong winds and aforementioned snow showers could lead to periods of BLSN and reduced visibility.

FSD WATCHES/WARNINGS/ADVISORIES

SD...Winter Weather Advisory from 3 AM to 9 PM CST Sunday for SDZ038>040-050-052>071. MN...Winter Weather Advisory from 3 AM to 9 PM CST Sunday for MNZ071-072-080-081-089-090-097-098. IA...Winter Weather Advisory from 3 AM to 9 PM CST Sunday for IAZ001>003-012>014-020>022-031-032. NE...Winter Weather Advisory from 3 AM to 9 PM CST Sunday for NEZ013-014.