textproduct: Sioux Falls

KEY MESSAGES

- A Red Flag Warning will continue through early evening for most locations. Please avoid burning and any activities that can spark a fire.

- A strong cold front moves through the area late tonight into Friday. Behind the front, much cooler air moves in and any rain may briefly change to a wintry mix and/or snow near and north of US Highway 14.

- Spotty showers and isolated thunderstorms are possible on Friday morning into mid afternoon. Severe weather is unlikely.

DISCUSSION

Issued at 157 PM CDT Thu Apr 16 2026

A strong LLJ will be in place tonight with some elevated instability, but a capping inversion will likely preclude any thunderstorm development. Strong southerly flow at the surface will keep temperatures very mild through the night, but a strong cold front will move into central SD later tonight will bring a quick drop in temperatures. This front will be near I-29 by sunrise and east of northwest IA and southwest MN by noon. There will likely be a small window in the morning near and east of I-29 that may allow for scattered showers and isolated thunderstorms to develop. With 1000 J/kg CAPE available a very isolated storm could produce hail to the size of quarters. For now the capping inversion will likely not allow for this stronger development.

Overall, temperatures should be falling through the day for most locations, likely stabilizing with a small rise near and west of I- 29. With wind gusts of 30 to 40 mph, elevated fire danger is expected. Some spotty very light showers will be possible but impacts will be minor.

A period of quiet weather will settle into the area Saturday through about Wednesday next week as a stronger northern stream jet keeps drier air in place. What will initially start as a cool day in the 50s on Saturday with breezy conditions will transition to a period of highs generally in the 70s Monday through Friday next week. Thursday into Friday upper level troughing moves into the Rockies with varying degrees of agreement on placement and strength of the potential system. Regardless this should bring the chance for showers and thunderstorms back into the forecast during this time as deeper southerly flow develops ahead of this system.

AVIATION /18Z TAFS THROUGH 18Z FRIDAY/

Issued at 1158 AM CDT Thu Apr 16 2026

South to southwest winds will gust to around 30 to 35 mph through the day and remain gusty tonight as well, with gusts around 25 mph more common. A cold front will move in later tonight in central SD then into southwest MN and northwest IA by late morning. Winds behind this front will gust to 30 to 40 mph. While precipitation chances are fairly low, scattered showers and isolated thunderstorms will be possible near and east of I-29 on Friday morning along with some MVFR ceilings.

FIRE WEATHER

Issued at 157 PM CDT Thu Apr 16 2026

Widespread red flag conditions are underway this afternoon will gradually improve this evening. Winds will remain fairly strong through tonight and turn to the northwest later tonight in central SD and on Friday morning along and east of I-29. Northwest winds behind this front will gust to 30 to 40 mph on Friday. Spotty showers and isolated thunderstorms are possible mainly near and east of I-29 Friday morning through mid afternoon.

High to very high fire danger are expected both Friday and Saturday due to the strong winds expected.

FSD WATCHES/WARNINGS/ADVISORIES

SD...Red Flag Warning until 8 PM CDT this evening for SDZ038>040- 050-052>071. MN...Red Flag Warning until 8 PM CDT this evening for MNZ071-072- 080-089-097-098. IA...Red Flag Warning until 8 PM CDT this evening for IAZ001-012- 020-031. NE...Red Flag Warning until 8 PM CDT this evening for NEZ013-014.