textproduct: Sioux Falls

KEY MESSAGES

- Light snow continues through mid-morning Wednesday. Snow totals of less than 1 inch expected for most of the region with narrow band of higher totals in our southeastern counties.

- High to Very High fire danger is expected by Thursday as strong winds and lowering humidity values return to the area. A Fire Weather Watch is in effect from 11AM until 9PM CST.

- Strong winds are expected to develop late Thursday afternoon and continue overnight into Friday. Gusts of 35-45 mph are expected with isolated gusts up to 50+ mph are possible. A High Wind Watch has been issued for the region from 10PM Thursday until 7AM Friday.

- All interested parties should monitor the forecast for next weekend. A more organized storm system in the Northern Plains may impact travel, and will bring much cooler temperatures to begin next week.

UPDATE

Issued at 1237 AM CDT Wed Mar 11 2026

Light snow continues as a wave passes through the region overnight tonight. Light snow will continue through Thursday morning. Overall guidance has shown a slight southeastward shift in QPF, with values increasing slightly over northwestern Iowa. After collaboration with neighbors have decided to increase QPF for this area with a blend of the NBM and CONSShort. Snow is expected to move southeast of the region by late morning to early afternoon Wednesday. Accumulations of less than an inch are expected for most of the region. A narrow band of higher amounts is possible along a rough line from northeast Nebraska, far southeastern South Dakota, and far northwestern Iowa and southwestern Minnesota. Here an 1 to 1.5 inches is expected with isolated pockets up to 2 inches possible.

On the backside of the wave a band of positive vorticity advection along with a weak push of WAA may be enough to trigger a very light round of precipitation Wednesday afternoon. Whether it's rain or snow will depend on the temperatures. North of I-90 it is more likely to be snow, with an additional accumulation of a dusting to a tenth or two. To the south it is more likely to be rain with just a hundredth or two possible. Any snow on the ground will not survive long as highs for Wednesday are expected to climb into the 40s. Winds will become west-northwesterly Wednesday afternoon, gusting 25- 30 mph. Winds decrease after sunset becoming light and variable. Lows will fall to the mid 20s.

Thursday afternoon winds increase, gusting to 30-40 mph. This coupled with low relative humidity will result in Elevated Fire Danger for most of the region. A Fire Weather Watch is in effect from 11AM until 9PM CST. For more details, please see the fire weather discussion below. Thursday late afternoon there is some indication of light rain showers developing across our northern reaches. However, with the very dry subcloud layer, there is high uncertainty on how much would make it to the surface.

Winds continue to increase overnight as a Clipper system passes just to the north of our region. Not only will this continue to tighten the SPG, but the temperature in the 925-850 mb layer will rapidly fall 10-15+ degrees C behind the cold front. This will work to bolster winds at the surface beginning in the evening and continuing overnight. NBM loaded far too low, so after discussion with neighboring offices have increased wind gusts Thursday afternoon through Friday morning with a blend of the NBM/NBM90. Frequent gusts of 35-45 mph are expected with occasional gusts to 50+ mph possible. Have decided to issue a High Wind Watch from 10PM Thursday until 7AM Friday.

DISCUSSION

Issued at 254 PM CDT Tue Mar 10 2026

CURRENTS & TONIGHT: A cooler day continues! Taking a look across the area, lower clouds and northeasterly surface winds have led to quite the temperatures gradient setting up across the area with low to mid 30s setting up along a Tyndall to Sioux Falls to Windom, MN line and mid 40s to low 50s along the lower Missouri River Valley and northwestern IA. While temperatures could slightly increase heading into the late afternoon, we'll likely see highs topping out in the upper 30s to low 50s across the area. Otherwise, the focus will shift northwestwards as a mid-level wave swings through our area this evening bringing a band of light snow. While things should start as light snow initially, can't rule out a brief transition to a rain/snow mix especially across far southeastern SD and northwestern IA as it encounters warmer surface temperatures with southeastern extent. Nonetheless, dynamic cooling should force things back light snow as we continue into the night. With this in mind, accumulative amounts of an inch or less are expected for most areas with the potential for slightly higher amounts (pockets of 2+ inches) across portions southwestern MN. will be less than inch for most areas. Lastly, should see light snow gradually taper off from northwest to southeast heading into Wednesday morning.

WEDNESDAY & THURSDAY: Looking into the midweek, any lingering light snow will continue to progress southeastwards eventually leaving our area by mid-morning on Wednesday. From here, mostly quiet conditions return as cloud cover gradually decreases. Depending on our new snow pack, temperatures could be a bit cooler north of I-90 especially across southwestern MN. As a result, highs could should continue to trend in the upper 30s to to upper 40s with the mildest conditions across the Missouri River Valley. Otherwise, increasing isentropic lift with an approaching wave could lead to a few light snow showers developing by Wednesday afternoon mainly across southwestern MN. While very light accumulations will be possible, some soundings do indicate some drier air could thwart much of it from reaching the ground. By Thursday, a decently strong clipper wave will swing through the Northern Plains and Great Lakes regions. While most of the better forcing will stay just north of our area. Most areas will be clipped by the southern side of the system leading to pockets of rain developing during the day on Thursday. Accumulative amounts will be on the lighter end (<0.10") for most areas. However, can't rule out up to 0.20 of an inch across portions of southwestern MN. Lastly, the return of mild and dry conditions along with increasing surface winds lead to elevated fire weather concerns by Thursday afternoon mainly across the Missouri River Valley (more in fire weather section).

FRIDAY ONWARDS: Heading into the extended period, an active pattern will continue aloft through at least Saturday. Persistent northwest flow will help usher in multiple system into the weekend potentially leading to accumulating snowfall on both Friday and Saturday. While some of the 10.12z guidance has started to come into better agreement with features, its still a bit early to pin-point a specific area of focus at this time. Nonetheless, with this system moving through around St Patrick's Day weekend; make sure to monitor your local forecast and be prepared to alter any travel plans. Otherwise, we'll get another taste of winter temperature-wise over the weekend with highs decreasing into the 20s to low 30s on Sunday and Monday.

AVIATION /06Z TAFS THROUGH 06Z THURSDAY/

Issued at 1237 AM CDT Wed Mar 11 2026

Breezy northerly winds gusting 18-23 kts will gradually become northwesterly and then slowly decrease toward the end of the period.

Light snow is currently progressing southeastward through the region. Have timed out snow onset and ending for all three TAF sites. Snow ends from the northwest to the southeast early Wednesday morning, completely clearing the region by mid-morning. Accumulations are expected to be light, less than an inch for most of the region.

A mix of VFR down to IFR ceilings and visibility will prevail for the first half of the period. Conditions improve as snow tapers off by late Wednesday morning, becoming VFR for the remainder of the period.

FIRE WEATHER

Issued at 1237 AM CDT Wed Mar 11 2026

Thursday afternoon southwesterly winds are expected to become gusty as the SPG tightens ahead of an incoming Clipper system. Good mixing through the 800 mb layer will allow us to tap into a 35-45 kt LLJ. In addition, very strong WAA will warm that layer to 6-12 degrees C. Mixing down to the surface may result in widespread gusts of 30-40 mph with an isolated gust to 45 mph possible. This will also work to boost surface high temperatures to the 50s and 60s, with the warmest temperatures south of a line from Huron to Sioux Falls, to Storm Lake.Soundings indicate a very dry boundary layer that will work to tank relative humidity values into 20-30% range south of that same line. North of there values increase. Despite the recent snow and snow melt, the warm conditions and strong winds will quickly dry out fuels. Grassland Fire Danger will reach the High to Very High Category. Considering these conditions have decided to issue a Fire Weather Watch for Thursday from 11AM until 9PM CST.

FSD WATCHES/WARNINGS/ADVISORIES

SD...Fire Weather Watch from Thursday afternoon through Thursday evening for SDZ038-050-052>055-057>071. High Wind Watch from Thursday evening through Friday morning for SDZ038>040-050-052>071. MN...High Wind Watch from Thursday evening through Friday morning for MNZ071-072-080-081-089-090-097-098. IA...Fire Weather Watch from Thursday afternoon through Thursday evening for IAZ001>003-012>014-020>022-031-032. High Wind Watch from Thursday evening through Friday morning for IAZ001>003-012>014-020>022-031-032. NE...Fire Weather Watch from Thursday afternoon through Thursday evening for NEZ013-014. High Wind Watch from Thursday evening through Friday morning for NEZ013-014.