textproduct: Sioux Falls

KEY MESSAGES

- Dry and seasonably mild conditions will dominate the week ahead with only very minor chances (<20%) for showers into early next week.

DISCUSSION

Issued at 117 PM CDT Thu Oct 1 2026

Cool, dry high pressure settles southward tonight leading to lighter winds and clearing skies. May be some mid/high level clouds so that could offset some of the potential radiational cooling. The NBM 10th percentile does sneak down to about 36 in parts of southwest MN and nearby locations, but for now expect low temperatures around 38 or higher with lower to mid 40s near and west of I-29. So, not a zero percent chance for patchy frost, but too low to issue any headlines.

High pressure slowly moves east on Friday, so expecting some cool high temperatures. Highs generally in the low to mid 60s. Southerly flow increasing in the afternoon west of I-29, then across the entire area Friday night. Lows may need to be increased a bit into the lower to mid 50s given the expected 925 mb temperatures.

Saturday will be warmer with southerly flow turning southwest during the afternoon. Highs more consistently in the upper 60s to lower 70s.

A cool front moves through Saturday night into Sunday bringing cool and dry conditions.

Monday will be dry and cool with highs in the 60s while southerly flow increases Tuesday into Wednesday ahead of the next wave, bringing a better potential for highs in the 70s.

A series of weak, moisture starved systems will move through the Northern Plains over the next 7 days, resulting in little to no impacts. The better chances for sprinkles or very light showers will be Friday and Saturday then again Monday into Tuesday. Both show waves moving by to the north with the tail end of forcing scraping by the area. Little to no instability with each wave coupled with abundant dry air leaves little in the way of precipitation production potential. Friday and Saturday looks like the better chance for a spotty shower will be north of I-90 where better mid level saturation is expected.

AVIATION /18Z TAFS THROUGH 18Z FRIDAY/

Issued at 1241 PM CDT Thu Oct 1 2026

VFR conditions expected for the period. Gusty winds up to 20 kts are possible until a little bit before sunset, clearing out of the northwest portion of the CWA near KHON first and stretching southeast through KFSD and down to KSUX. Winds overall trending down over the period, switching to light and variable for much of the area around 3-4z. Ceilings to drop slightly through the period, though non-impactful for category change.

FSD WATCHES/WARNINGS/ADVISORIES

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