textproduct: Sioux Falls

KEY MESSAGES

- Wintry precipitation expected north of I-90 tonight into Thursday. A bigger threat for sleet and freezing rain than snow. Winter Weather Advisory for Highway 14 corridor and SD Highway 34/MN Highway 30. Close attention needs to be paid to the Buffalo Ridge area in southwest MN where there is a small threat for a quarter to a third of an inch of freezing rain if sleet is not as prevalent.

- Much needed rainfall will move into the area tonight and continue into Thursday morning. A few rumbles of thunder are possible. Much of the area will see a half an inch to an inch of rain/total liquid precipitation.

- Isolated thunderstorm potential very late Thursday night into Friday morning in northwest IA and nearby locations. Severe weather unlikely but some dime sized hail would be possible.

- Friday is a tricky day with the potential for freezing rain and sleet. The better chances for snow should be mostly northwest of the area. Enough of an icing threat that some minor to moderate impacts will be possible. Better chances from the morning into early afternoon.

- Saturday will bring scattered snow showers with the potential for wind gusts of 35 to 45 mph within these showers. This would cause locally rapid drops in visibility.

UPDATE

Issued at 1239 AM CDT Thu Apr 2 2026

As mentioned in the previous discussion, the thermal profile is key in determining precipitation type at the surface. We've already seen some areas along and north of Highway 14 transitioning back and forth between rain and snow. This is the result of ongoing WAA in the 925-850 mb layer and surface dew points remaining above freezing. Over the next couple of hours, CAA will win out beginning over central South Dakota and work east, resulting in a wintry mix to all snow. Mixed rain and snow may push as far south as the I-90 corridor. Along and south of I-90 the primary precipitation type will be rain.

Of greater concern is the possibility of ice accumulation in southwest Minnesota. Here the warm layer stays above freezing longer, while the surface temperatures fall to or below freezing after midnight. This type of profile most often leads to freezing rain or sleet. Model soundings indicate the primary precipitation type will be sleet, but there could be periods of back and forth between sleet and freezing rain. Accumulations of sleet could be as high as half an inch to an inch. Accumulation of ice from freezing rain is very uncertain, however a tenth to two tenths are possible by Thursday morning, especially along and east of Buffalo Ridge. This could result in impacts to your morning commute. Please allow yourself some extra time in the morning to get to your destination.

Zooming out a bit, we can see the surface low that will pass to the south of our forecast area and then turn northeast. As it does so divergence aloft and positive vorticity advection set the stage for modest forcing for ascent. While the better dynamics are located just to the south and east of our forecast area, a few thunderstorms are possible for areas of northwestern Iowa Thursday morning. While severe is not expected hail up to the size of a dime may be possible. By late morning we will begin to see the precipitation tapering off from west to east. The afternoon and evening should be mostly dry. Highs will climb to the mid 30s to upper 40s.

Hot on the heels of this system is another system taking aim for Friday and Saturday. For more details please see the full discussion below.

DISCUSSION

Issued at 127 PM CDT Wed Apr 1 2026

For tonight into Thursday morning the thermal profile is everything. A couple of degrees one way or the other in the lowest 5 thousand feet will determine whether or not rain, freezing rain, sleet or snow falls. The biggest things to watch will be the trends in the warm layer aloft and the surface dew points which will determine the surface wet bulb temperature and whether or not the surface temperature remains above 32 or at or below 32. The best chance for freezing rain will be over parts of southwest MN where the thermal difference between sleet and freezing rain is very small. The heaviest freezing rain and sleet amounts will likely be late tonight into Thursday morning and will affect the morning commute for those areas. For now within the advisory area, believe that sleet will be more abundant than freezing rain with upwards of a half an inch to an inch of sleet potential. Thursday afternoon will see most of the precipitation threat shifting northeast of the area with temperatures warming into the 30s near and north of I-90 and the 40s south.

Late Thursday night into Friday morning could see a few thunderstorms as 500-1000 J/kg CAPE move into northwest IA and nearby locations. Severe weather unlikely but dime sized hail will be possible.Away from the thunderstorm potential, surface temperatures will again play a role in precipitation type Friday with model soundings hinting at more of a rain/sleet/freezing rain threat vs. snow. With some instability on Friday morning will also see some potential for some locally better rates. By afternoon the potent mid level wave will swing a dry slot into the area with most locations near and east of I-29 seeing precipitation come to an end. Areas near and west of the James River still seeing some lift, frontal forcing and saturation on the backside of the system which could lead to some snowfall.

The system wraps up on Friday night into Saturday with fairly strong northwest winds from the surface to about 300 mb. Model soundings showing the dgz lowering as the colder air wraps in and some weak instability develops within the mixed layer from about the surface to 850 mb. The combination of the lower dgz and shallow instability will likely lead to scattered snow showers with the potential for some 35 to 45 mph gusts within these showers. This could lead to brief, rapid drops in visibility if everything comes together. As a note, the CIPS snow squall model guidance is in the two highest categories on Saturday.

Sunday through the middle of next week will see northwest flow aloft turn more westerly which will bring a bit of warming. Overall threat for any meaningful precipitation is very low.

AVIATION /06Z TAFS THROUGH 06Z FRIDAY/

Issued at 1239 AM CDT Thu Apr 2 2026

MVFR to IFR ceilings and visibilities will prevail most of this period, with brief pockets of LIFR possible. Numerous light showers are ongoing, with rain from I-90 south. To the north as you approach the Highway 14 corridor a mix of rain, rain and snow, sleet, and freezing rain are possible. The area most likely area to see freezing rain is northwest Minnesota. Here, accumulations of ice of a tenth to two tenths is possible. Impacts to flight operations, especially slippery runways are possible. Precipitation ends from west to east around mid-morning. Ceilings begin to improve shortly after that but will likely remain MVFR through the end of the period.

Winds are currently easterly gusting 20-25 kts, with the highest gusts east of the James River Valley. Winds will gradually turn northeast through the morning becoming northerly by afternoon. Winds decrease and become light in the late afternoon.

FSD WATCHES/WARNINGS/ADVISORIES

SD...Winter Weather Advisory until 6 PM CDT this evening for SDZ038>040-055-056. MN...Winter Weather Advisory until 6 PM CDT this evening for MNZ071- 072-080-081-097. IA...None. NE...None.