textproduct: Sioux Falls

KEY MESSAGES

- QUIET AND MILD: Dry conditions and above normal temperatures continue through Wednesday with highs in the 50s and 60s.

- MINIMAL RAIN INTO THE WEEKEND: Besides a few sprinkles north of I-90 late this evening, most areas should remain dry into the weekend.

- COLDER AIR AHEAD: A strong front drops temperatures significantly Thursday and Friday, though temperatures will gradually warm above normal by the end of next weekend.

UPDATE

Issued at 230 AM CST Tue Nov 10 2026

Taking a look across the area, another quiet night continues as a surface high gradually progresses across the area. While lighter surface winds could lead to some patchy valley fog at times, we're continuing to see short-range guidance back off coverage this morning. With this in mind, decided to strip it out of the visibility grids for most areas. Otherwise, expect the quieter conditions to hang around for most of the day as strengthening warm air advection (WAA) increases cloud coverage. This combined with the arrival of a cold front will limit temperatures to the upper 50s to mid 60s for the day. While most areas will stay dry, can't completely rule out a few isolated sprinkles to very light showers north of I-90 late this evening. Lastly, an influx of arctic air behind this front will plummet temperatures into the 30s and 40s for highs and 20s to 30s for overnight lows from Wednesday onwards so make sure to dress appropriately.

DISCUSSION

Issued at 1200 PM CST Mon Nov 9 2026

THIS AFTERNOON: A weak frontal boundary has moved through the forecast area this afternoon. A warm westerly northwesterly flow behind the front continues to allow temperatures to surge into the 60s. By this evening, a light to even variable wind may develop.

TONIGHT: Outside of scattered high lvl cirrus, a rather quiet overnight period is expected. The light and variable winds that develop will promote strong radiational cooling, dropping low temperatures near the freezing mark. Some high resolution models such as the HRRR/RRFS/RAP indicate enough cooling for valley/river based fog to develop.

TUESDAY: Southwesterly surface winds will increase through the day on Tuesday as a progressive open wave begins to cross the Northern Rockies. This wave induces surface cyclogenesis across the western Dakota early in the day, increasing the SPG over the Tri-State area. With modest low-lvl warm advection in place, it's possible that temperature may warm higher than what the NBM suggests. Will trend temperatures towards the 90th percentile, indicating upper 50s to lower 60s. The relatively moisture starved trough will move through the Plains Tuesday night, pushing the surface low into Western Minnesota late in the evening and bringing strong cold advection through the Dakotas. Wind gusts through the James and Missouri River valleys have potential to reach the 35 to 45 mph range which has led me to bump winds upwards. Some questions continue on the depth of the low-lvl moisture field, which could produce a sprinkle as it moves through. The latest ensemble guidance continues to back off on the probabilities of any measurable rain (<20%).

WEDNESDAY: By Wednesday morning, the development of a large ridge over the western CONUS and a trough over the eastern CONUS will put the CWA into zone of strong cold advection. The initial surge of cold air early Wednesday won't be nearly as strong as the secondary surge that arrives Wednesday night. Thus, temperatures Wednesday afternoon may still rise into the 50s.

THURSDAY-FRIDAY: Under the influence of a modifying arctic airmass at the end of the week, temperatures will fall below normal with highs only near 40 degrees and morning lows likely to fall into the middle 20s by Friday morning. No precipitation is expected.

SATURDAY-MONDAY: Regional weather will remain very quiet through next weekend and into the early portions of next week. Mid- lvl ridging will slowly transition eastward during the weekend, allowing a slow increase in southerly to southeasterly surface winds Saturday. These winds will increase further on Sunday, introducing very low fire danger risks with gusts over 20-30 mph. Temperatures will continue to warm through the weekend, but slowly as low-lvl warm advection is not intense, and SE surface flow is less conducive to strong warming. Nevertheless, by Sunday and Monday we'll see highs back above normal into the 50s.

AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/

Issued at 1039 PM CST Mon Nov 9 2026

Patchy light fog is expected to develop through daybreak, though widespread issues are not expected. As such, most locations won't see any fog, but enough confidence to include at least a couple of hours of visibilities down to the 3-5SM range at KSUX and KHON. Any fog should lift by 10.14Z. Otherwise, VFR conditions are expected through the period.

Winds remain light to calm through the early morning hours, with southerly winds around 5-10 kts (slightly higher in south-central South Dakota) returning through the day today. A low pressure system moves across the Highway 14 corridor to end the period, taking a cold front along with it that will stretch southwest from the low. As this system moves through, winds will turn to the northwest. Lastly, LLWS concerns may return at the end of the period, but confidence was not high enough to include in the TAFs at this time.

FSD WATCHES/WARNINGS/ADVISORIES

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