textproduct: Sioux Falls

KEY MESSAGES

- Near critical fire weather conditions this afternoon across portions of southeast South Dakota, northwest Iowa, and northeast Nebraska. Any fire may spread quickly. Conditions will improve after sunset.

- A Fire Weather Watch is in effect for portions of southeast South Dakota, northwest Iowa, and northeast Nebraska from 11 am to 6 pm CST Friday. A combination of strong winds and low humidity may lead to critical fire weather conditions. Burning should be avoided as any fire may spread quickly.

- Accumulating snow is expected late Friday night into Saturday morning. Snow amounts from 1-2 inches are expected for areas mainly along and north of I-90. Locally higher amounts may fall in a narrower band.

- A more active weather pattern is expected next week. While there is still a wide variation in forecast guidance, there will be multiple chances for precipitation. Precipitation type will depend on temperatures.

DISCUSSION

Issued at 220 PM CST Thu Feb 26 2026

Currently watching several observation sites flirt with Red Flag Warning criteria. While RH has dropped below 30 percent for much of the area and some spots below 20-25 percent, there have been hour to hour fluctuations in winds. Would like to see a more consistent higher end wind to justify the issuance of a headline. Will cover these near critical conditions with a Special Weather Statement through the afternoon. Conditions should improve rapidly after sunset as surface winds decouple and humidity increases.

Attention then turns to tomorrow. Another warm, dry, and breezy day. See the Fire Weather section below for more details.

A potent short-wave in northwest flow then drops south across the southern Canadian Prairies on Friday with its attendant surface cold front moving through the forecast area Friday night into Saturday. Along this frontal boundary, expect the development of some light snow. All guidance is showing a band of snow oriented northwest to southeast across SD/MN/IA, but there are differences in exact placement. A blended solution suggests the area most likely to see accumulating snow along and north of I-90. Right now, 1-2 inches seem reasonable, although model soundings show several hours of a saturated profile within the dendritic growth zone. This may lend to a narrower band of higher snow that may require winter headlines. Highs Saturday will range from near 20 degrees along the Buffalo Ridge to the mid-30s along the Missouri River Valley.

Continued cold into Sunday with another chance for light snow as a more subtle wave moves through northwest flow aloft. 12Z model suite is split with the GFS/NAM farther south with any precipitation and the ECMWF/GEM a bit farther north. Moisture is not as impressive with this wave, so any accumulation appears minimal.

Temperatures moderate into next week with a fairly significant change in the 500 hPa synoptic pattern. There's agreement in large scale troughing across the western CONUS, but wide variation in when and how strong any individual waves lift northeastward into the Northern Plains. At this time, temperature profiles suggest above freezing values during the day and below freezing at night. Therefore, precipitation type will be highly dependent on time of day. For now, NBM broad brushed 20 to 40 POPs for next week seem reasonable.

AVIATION /18Z TAFS THROUGH 18Z FRIDAY/

Issued at 1125 AM CST Thu Feb 26 2026

VFR conditions will be the rule at all TAF airfields through 27.18Z. With mostly sunny/clear skies, the primary concern will be breezy northwest wind this afternoon and again late in the period Friday morning. Expect gusts from 18-25 kts with higher values along and north of I-90. Otherwise, winds diminish quickly near sunset with light south-southwest flow this evening and overnight.

FIRE WEATHER

Issued at 220 PM CST Thu Feb 26 2026

Friday will be warm, dry, and windy. Expect minimum RH similar to today with the lowest values along the Missouri River Valley. Main difference tomorrow will be more consistent, stronger winds. Model soundings suggest deep mixing by mid-afternoon up to around 6000 ft agl with at least 30 kts at the top of the boundary layer. Some of the more aggressive guidance shows 40+ knots. The best overlap of stronger winds and low humidity exists from Charles Mix to Plymouth/Woodbury Counties. For these areas, have issued a Fire Weather Watch from 11 am to 6 pm CST. Burning should be avoided tomorrow as any fire may spread rapidly. Given conditions this afternoon, later shifts may need to consider a possible spatial expansion northward of any updated fire weather headlines.

FSD WATCHES/WARNINGS/ADVISORIES

SD...Fire Weather Watch from Friday morning through Friday afternoon for SDZ050-063-068>071. MN...None. IA...Fire Weather Watch from Friday morning through Friday afternoon for IAZ020-031. NE...Fire Weather Watch from Friday morning through Friday afternoon for NEZ013-014.