textproduct: Sioux Falls

KEY MESSAGES

- Sporadic gusts of 60 to 65 mph have developed in central South Dakota this morning and similar conditions will spread east toward the Buffalo Ridge in southwest Minnesota. A High Wind Warning has been issued mainly north of I-90 for this morning.

- Strong west winds gusting 40 to 50 mph and very low humidity levels will result in critical fire weather conditions along and south of Interstate 90 today. A Red Flag Warning is in effect from 10 AM to 6 PM. Outdoor burning should be avoided.

- The potential for accumulating snow returns Thursday into Thursday night. The best chance for at least an inch of snow (40-60%) is south of I-90 at this time. A narrow band of 2-4+" inches may set up over parts of our area, though uncertainty in the placement of this heavier band remains high.

UPDATE

Issued at 450 AM CST Wed Feb 18 2026

Sporadic gusts of 60 to 65 mph have been observed in central South Dakota early this morning and RAP guidance suggests similar conditions will expand east toward the Buffalo Ridge in southwest Minnesota through mid-late morning. A High Wind Warning has been issued mainly north of I-90 for this morning, still followed by the Wind Advisory for a few hours to cover the winds slowly decreasing through the afternoon.

Issued at 330 AM CST Wed Feb 18 2026

Very windy conditions have arrived as anticipated with west winds gusting 40 to 55 mph expanding east across the forecast area. Have seen isolated 60 mph gusts but confidence in the extent/persistence of these higher gusts is low so will stick with the Wind Advisory at this time. Did further refine the advisory timing, extending areas from Brookings/Sioux Falls, east through southwest Minnesota and most of northwest Iowa until 3 PM.

Precipitation chances generally remain unchanged in the latest guidance. Could see light snow sneak a bit further south toward the Highway 14 corridor today with very light accumulation less than a half inch possible from Brookings to Marshall/Tracy MN.

For Thursday's system, focus remains south of I-90 with the highest probabilities for exceeding 1" (50-60%) and 2" (30-50%) south of Highway 18. Models continue to show potential for a narrow band of 2-4+" band which could impact locations along Highway 20, however still some variance in the location of this narrow band, so no headlines at this time.

For this weekend into early next week we return to a dry pattern but with temperatures much closer to normal for late February.

DISCUSSION

Issued at 240 PM CST Tue Feb 17 2026

One last very warm February day out there, with temperatures having climbed mainly into the 60s. It's been a breezy day too, and these winds will diminish this evening, at least for a few hours. A cold front will be moving through the area this evening as well and will help provide some lift for showers to develop. These showers will actually some elevated instability to work with, and thus a few thunderstorms cannot be ruled out. Can't entirely rule out an isolated severe storm as there will be ample dry air beneath these elevated storms. This would mean gusts potentially as high as 60 mph, but widespread strong to severe storms are not expected. Synoptic winds will increase through tonight as strong cold air advection pushes into the area behind the cold front, with gusts up to 50 mph expected. This will be the case especially for areas north of I-90 where the Wind Advisory has been expanded to include the rest of southwest Minnesota north of I-90. These stronger winds will spread into northwest Iowa heading into tomorrow morning, but the current thinking is the chances for these stronger wind gusts in excess of 45 mph will only last an hour or two, so did not expand the advisory at this time and will be captured by the Fire Weather Watch. More on that in the fire weather discussion later on.

Some wrap-around precipitation may impact mainly the Highway-14 corridor late tonight into tomorrow morning. This will likely start as light to very rain, turn to light to very light snow, and then back to rain before exiting. Not expecting any snow with this to accumulate, but there could be very brief reductions in visibility in any light snow due to the stronger winds that will be in place during the morning commute tomorrow. Temperatures turn cooler heading into the day tomorrow behind the aforementioned cold front, with highs mainly in the 40s and 50s. Of course, this is still above normal, but it only gets colder from here.

Heading into Wednesday night and Thursday, a surface low will move across the central Plains, with most guidance then pulling the system northeastward to the Great Lakes by Thursday night/Friday. 17.12z guidance has continued to show the southerly trend of the low through the central Plains as shown in the 17.06z guidance, and this has lead to the latest NBM pulling the 2+ inch snow amounts farther south and east closer to a Sioux City, IA to Jackson, MN line. Looking at the 17.12z ensembles, there appears to be less of a noticeable southerly trend as some of the deterministic models, so it's entirely possible the next suite of deterministic guidance starts to pull the snow farther north again. All that to say, still a lot of uncertainty in exact amounts, but even with light snow, reductions in visibility will be possible due to breezy conditions. As of now and based on the current forecasted track of the system, most spots south of I-90 look to see a moderate (40-60%) chance of snow of at least one inch of snow. There may be a narrow stripe of 2- 4+" of snow depending on where the heaviest band of snow moves through. This would be favoring areas closer to the Highway-20 corridor at this time, but again uncertainty remains high on where this band sets up, so be sure to keep up to date with the latest forecast. Chances of greater than 4 inches of snow remains low (<20%), but can't be completely ruled out.

For timing, look for some light snow to start to move into the Missouri River Valley by Thursday morning, with snow chances gradually lifting northeastward through the afternoon and evening. Snow should exit from northwest Iowa and adjacent southwest Minnesota Thursday night. Not much time to look into the long-range forecast, but temperatures do look to be colder heading into the weekend. Highs return mainly to the 20s and 30s with lows down in to single digits, though temperatures could trend colder or warmer depending on how much snow falls.

AVIATION /12Z TAFS THROUGH 12Z THURSDAY/

Issued at 450 AM CST Wed Feb 18 2026

Very strong west winds today will be the primary aviation concern, with gusts 40 to 60 mph early this morning slowly decreasing from west to east through the day.

MVFR ceilings and a potential for MVFR-IFR visibility in snow could impact areas north of I-90, with the better chances for visibility reductions toward the Highway 14 corridor. Areas along/south of I-90 should see VFR conditions through the period.

FIRE WEATHER

Issued at 330 AM CST Wed Feb 18 2026

Strong west winds gusting 40 to 55 mph early this morning will ease very slowly through the day, with gusts of 30 to 45 mph persisting well into the afternoon. Very dry air expanding across the region will drop afternoon relative humidity levels as low as 15 percent toward the Highway 20 corridor to 25 to 30 percent along I-90. This combination of strong winds and very dry air will produce critical fire weather conditions by late this morning along and south of I-90, and a Red Flag Warning remains in effect from 10 AM through 6 PM CST.

Much more seasonal temperatures settle into the region Thursday, accompanied by a chance for accumulating snow in some areas. This should limit the fire danger from Thursday through at least early next week.

FSD WATCHES/WARNINGS/ADVISORIES

SD...Wind Advisory until 3 PM CST this afternoon for SDZ062-067. Red Flag Warning from 10 AM this morning to 6 PM CST this evening for SDZ050-057>071. Wind Advisory until noon CST today for SDZ050-059>061-063>066- 068>071. High Wind Warning until noon CST today for SDZ040-055-056. Wind Advisory from noon today to 3 PM CST this afternoon for SDZ040-055-056. High Wind Warning until 9 AM CST this morning for SDZ038-039- 052>054-057-058. Wind Advisory from 9 AM this morning to noon CST today for SDZ038-039-052>054-057-058. MN...Wind Advisory until 3 PM CST this afternoon for MNZ081-089-090- 098. Red Flag Warning from 10 AM this morning to 6 PM CST this evening for MNZ089-090-098. High Wind Warning until noon CST today for MNZ071-072-080-097. Wind Advisory from noon today to 3 PM CST this afternoon for MNZ071-072-080-097. IA...Wind Advisory until 3 PM CST this afternoon for IAZ001>003- 012>014-021-022-032. Red Flag Warning from 10 AM this morning to 6 PM CST this evening for IAZ001>003-012>014-020>022-031-032. Wind Advisory until noon CST today for IAZ020-031. NE...Red Flag Warning from 10 AM this morning to 6 PM CST this evening for NEZ013-014. Wind Advisory until noon CST today for NEZ013-014.