textproduct: Sioux Falls

KEY MESSAGES

- Near to below normal temperatures will dominate the work week with highs in the 50s to lower 60s. - Outside of sprinkles this afternoon, scattered rain returns by Thursday with a 60-80% probability of greater than 0.10" of rain.

- Nighttime lows may locally dip into the mid-upper 30s through Friday, but more widespread 30s with light winds/clear skies and a better frost potential will be Friday night/Saturday morning.

- Warmer temperatures return through the weekend into early next week with highs back above normal.

DISCUSSION

Issued at 1247 PM CDT Tue Oct 13 2026

Some very weak elevated instability and mid level moisture will move through the area this afternoon and early evening. Very light showers and sprinkles remain possible during this time with no impacts expected.

Winds decrease through the night with temperatures expected to fall back into the low to mid 40s, with a few spots in the upper 30s. The better chance for lows in the 30s will be near highway 14 and in the mid James Valley. For now will not issue a frost advisory as some of the models are hinting that a stratus deck around 1500 feet could develop later tonight which would limit the radiational cooling and frost potential.

Broad warm advection increases on Wednesday night ahead of a wave moving into NE. This forcing continues through a good portion of Thursday, so expect rain late Wednesday night into Thursday. Instability pretty negligible so do not expected any thunderstorms. Rainfall amounts should be highest south of I-90 where a quarter to a half an inch should be more common. The latest Canadian Ens, EC Ens and GEFS show about a 30 to 60 percent chance to exceed a half an inch south of I-90.

Thursday will become breezy with cool temperatures as rain comes to an end in the afternoon and evening. Highs should mostly be in the 50s.

While Saturday morning will be on the cold side, there are still come concerns that southerly return flow could set up early enough Friday night to avoid widespread frost and freeze. Right now, northwest IA and nearby locations appear to see the best chance for light winds late Friday night into Saturday morning and thus the better chance for frost.

Weak ridging and westerly flow aloft will develop Saturday into Sunday, bringing temperatures back to near to above normal during this time. Upper level ridging strengthens early next week and continues through mid week as a large trough deepens over the Rockies. This should support above normal temperatures and mainly dry conditions.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 1247 PM CDT Tue Oct 13 2026

Mostly VFR conditions through the period. Some patchy MVFR ceilings will be possible, mainly in northwest IA this afternoon and late tonight into Wednesday morning north of I-90.

FSD WATCHES/WARNINGS/ADVISORIES

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