textproduct: Sioux Falls

KEY MESSAGES

- Near to above normal temperatures will continue into the new week with highs mainly in the 80s to mid 90s. Heat indices may approach the upper 90s in spots Monday and Tuesday afternoon.

- After a brief break from severe weather through Monday, the chances for a few strong to severe storms will increase starting late Monday and again by Tuesday night. Keep up to date with the latest forecast!

DISCUSSION

Issued at 136 PM CDT Sun Jul 5 2026

CURRENTS & TONIGHT: A summer-like day continues! Taking a look across the area, quieter conditions persist this afternoon with many areas observing temperatures in the low to upper 80s. This combined with dew points in the upper 60s to low 70s and light winds has led to a picture perfect summer afternoon. With no rain expected in the forecast today mainly due to strengthening ridging, this would be a perfect time to hit the water park/pool and enjoy something cold like ice cream. Otherwise, the seasonable conditions will carry over into the overnight hours as temperatures only decrease into the low to upper 60s for the night.

MONDAY-WEDNESDAY: Looking into the new week, the previously mentioned ridging will begin to flatten by Monday giving way to more quasi-zonal flow aloft. With strengthening mid-level warm air advection (WAA) in place and a return to southerly surface winds, temperatures will continue their gradual increase during the early week leading to daily highs in the mid 80s to mid 90s through Tuesday. This combined with dew points in the upper 60s to low 70s will lead to heat indices in the mid to upper 90s with the most oppressive conditions west of I-29. While this falls just short of heat advisory criteria, make sure to stay hydrated and take frequent breaks if working outdoors! Otherwise, the flow pattern aloft will usher in multiple waves through midweek lead to near-daily chances for a few stronger storms. Starting on Monday, a cold front will stall out roughly from the Black Hills to Northeastern SD. As this front is intersected by an approaching shortwave, scattered showers and thunderstorms will develop with a few potentially becoming severe.

While there are still some questions as to if this developing activity can sustain itself with the limited shear (15-30 kts), there should be at least a low chance (30%-40%) for a few storms to make their way into areas along and south of the U.S. Highway-14 corridor through early Tuesday morning. Nonetheless, if this pulsy activity can maintain its intensity; the main hazards would be up to quarter-sized hail and 60 mph winds gusts. The next chances potentially come from Tuesday night into Wednesday as the stalled boundary lifts towards the ND/SD border and is intersected by a slightly stronger wave generating scattered showers and thunderstorms. While there is still some uncertainty as to how far north the boundary lifts, confidence in our severe weather potential has lower a bit due to the better forcing being just north of us and limited shear/instability. However, we could at least get some pockets of moderate to heavy rainfall out it with PWATs between 1.25" to 1.75" inches and deeper warm cloud depths. While flash flooding is not expect, localized ponding will be possible in any areas that receive prolonged accumulations with this developing activity.

THURSDAY ONWARDS: Heading into the extended period, an active period will continue aloft as quasi-zonal flow continues into the weekend. Multiple waves will progress through the plains leading to at least some smaller chances (<30%) through Saturday. With the ridging expected to strengthen over the western CONUS during the upcoming weekend, we could see the return of oppressive temperatures mainly in the 90s to low 100s as early as Sunday. With heat indices potentially reflecting similar values, make sure to stay hydrated and to monitor your local forecast!

AVIATION /18Z TAFS THROUGH 18Z MONDAY/

Issued at 1228 PM CDT Sun Jul 5 2026

VFR conditions will continue this TAF period. Besides a few diurnally driven sprinkles, no aviation concerns are expected. Otherwise, Light southeasterly winds will become more southerly by Monday afternoon to end the TAF period.

FSD WATCHES/WARNINGS/ADVISORIES

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