textproduct: Sioux Falls

KEY MESSAGES

- Roller coaster temperatures are expected for the week ahead with spotty chances for precipitation throughout mid-week. Better chances fall along the Missouri River Valley Monday and into northwest Iowa on Tuesday, both of which could be light snow or a rain/snow mix.

- Warmer days today and Wednesday will also be on the breezier side, resulting in areas of elevated fire danger.

- A potential pattern change late week into the weekend may bring better chances for precipitation to the area during this time.

UPDATE

Issued at 440 AM CDT Sun Apr 5 2026

Forecast is on track early this morning with modest west to northwest winds 5-15 mph holding temperatures in the upper 20s to mid 30s as of 4 am.

Previous update below addresses uncertainty in the degree of warming today with differences in timing of an advancing cold front. That said, deep west-northwest flow ahead of the front should favor strong mixing and have nudged highs up a degree or two, though there is still room for more warming in the broader guidance spectrum with highs still near to slightly below the 50th percentile of the latest NBM. The mild, breezy conditions bring a return of elevated fire danger, mainly in portions of southeast SD where precipitation totals were lowest over the past few days.

Chances for additional precipitation over the next few days will be spotty, with better chances focused along a mid-level front near the Missouri River Valley Monday, then in response to warm advection across northwest Iowa on Tuesday. In both cases, the thermal profiles would support a period of light snow or perhaps a rain/snow mix. However, with only a low (<20%) probability that 48-72 hour total QPF will exceed 0.25", snowfall amounts should be rather light.

Temperatures rebound nicely for Wednesday, again in response to a breezy southwest to westerly flow which will support another day of elevated fire danger.

Issued at 943 PM CDT Sat Apr 4 2026

Winds have diminished across the area, and this may allow for some patchy light fog to develop in areas that saw snowmelt earlier today. Winds will remain elevated enough to prevent widespread issues from occurring, but trends will be monitored in case winds go lighter than expected. Otherwise, temperatures are still on track to drop to the upper 20s by daybreak.

An upper wave moving across northern Minnesota will send a cold front through the area tomorrow afternoon and evening, and there will be just enough lift to get a few rain showers going primarily over southwest Minnesota. This is where soundings show just enough elevated instability to allow for some of these showers to overcome the dry sub-cloud layer. Farther south and west, the dry sub-cloud layer will likely be too much for the rain to overcome, so only expecting virga farther west across the area. These showers/virga may also bring down some stronger wind gusts up to 40 mph as it moves through the area. Highs on Sunday will range from the low 60s across the Missouri River Valley to the around 50 degrees along Highway 14. The Highway 14 corridor will have the greatest uncertainty high temperature wise due to the timing of the cold front, as evidenced by a difference of around twenty degrees between the NBM 10th and 90th percentiles. A faster cold front would mean highs stay mainly in the low 40s along Highway 14, but a slower front than expected could result in highs approaching the 60 degree mark there.

Otherwise, breezy conditions will continue into Sunday evening with a push of cold air advection expected following the frontal passage. This colder air filtering in will also allow for temperatures to drop to the low 20s north to upper 20s/low 30s south by Monday morning.

DISCUSSION

Issued at 1241 PM CDT Sat Apr 4 2026

Wrap around snow will continue to slowly drift east and northeast through early evening. Precipitation should mostly come to an end by late afternoon as the upper level low pushes east and drier air moves in. With the chilly air mass in place lows will again be in the 20s.

Deep northwest flow will bring the next wave to the north of the area on Sunday which could bring some patchy light rain to parts of southwest MN, but chances remain low. A nice little bump in temperatures ahead of this wave with highs from the lower 60s along the Missouri River and in the 50s most other locations. Will likely see some falling temperatures late afternoon near and north of I-90 as the cold front drops south. Will likely see some gusts from the northwest of 25 to 35 mph with strong cold air advection from late afternoon through about midnight. This will bring a chilly Monday morning with lows possibly into the teens near highway 14 and 20s elsewhere.

Monday will be a chilly day with highs in the 30s and 40s and a north wind of 10 to 20 mph. A weak system will bring some mid level frontal forcing to the Missouri River Valley with some patchy light rain and light snow possible. For now amounts look fairly low.

Low pressure will deepen over MT on Tuesday and ahead will swing a wave onto the Plains. Overall the threat for meaningful precipitation is low, but some patchy light rain and light snow is possible. A quick look at the soundings hints that saturation aloft moves in, but the low levels remain dry. By the time the low level saturate a bit, the upper level begin to dry out so the overlap will likely be short lived. There is some weak elevated instability in mainly northwest IA which could help sustain a little bit of precipitation.

This deeper low pressure in MT will swing into the Northern Plains Wednesday and bring a shot of warmth with highs in the 60s most locations. There will be a chance for some light rain or light snow Wednesday into Thursday, but the majority of the forcing with this wave will be to the north. Winds will turn gusty Thursday afternoon and Thursday night as the system passes by to the north.

The southern stream jet becomes more active late in the week into next weekend as a trough of low pressure develops over the western U.S. This should bring our next better chance for precipitation. The latest Canadian and GEFS 50th percentile ensemble output showing a half an inch to an inch of precipitation during this time wile the ECMWF Ens is hanging on to dryer conditions. This is likely due to the ECMWF indicating a weaker western U.S. trough. Will keep an eye on this as this system would likely produce rain and snow.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 645 AM CDT Sun Apr 5 2026

VFR conditions will be most prevalent through the TAF period. Exceptions will be some early morning MVFR fog along the western fringe of the Coteau des Prairies in east central South Dakota, not expected to impact KHON, but locations east toward De Smet. Could also see MVFR stratus behind a cold front late in the period. Confidence is too low to indicate an MVFR ceiling at this time, but did highlight potential timing with SCT015-020 mention for now.

Finally, west-northwest winds will increase by midday with gusts 25-30kt more common from 18Z through sunset or shortly after (01-02Z).

FSD WATCHES/WARNINGS/ADVISORIES

SD...None. MN...None. IA...None. NE...None.