textproduct: Sioux Falls

KEY MESSAGES

- Temperatures through much of this week will be on the warm side of average for this time of year, with highs in the upper 40s and 50s, and lows in the 30s to mid 40s.

- A period of breezy to gusty winds are expected today through much of the week. Areas along and west of I-29 will see frequent gusts of 25-35 mph with occasional gusts up to 45 mph possible on Tuesday.

- Continued dry and windy conditions may result in elevated fire danger through Tuesday and possibly Wednesday.

- More active weather looks likely around Friday/Saturday. Rain should be the main precipitation type with an isolated thunderstorm possible.

DISCUSSION

Issued at 1251 PM CST Sun Nov 15 2026

The main story through Tuesday will be strong southerly winds and dry conditions. Slow moving surface high pressure to the east and a deepening low pressure over the Northern Rockies will bring a strong surface pressure gradient to the Northern and Central Plains. Model sounding mixed layer suggests winds should gust to 25 to 35 mph on Monday and 35 to 45 mph on Tuesday. Both days should see elevated fire weather concerns, with the surface relative humidity being the only real negative factor with afternoon minimum relative humidity only falling to 55 to 65 percent.

Surface low pressure moves onto the Plains Wednesday which will keep very strong winds in place, likely strongest east of Highway 81.

Wednesday afternoon and evening will see a fairly dynamic wave swing through. Rapid cooling aloft in the 700-500mb layer may bring a brief period of instability as a cold front swings through at the surface. The combination of this lift along the front and the cooling aloft may allow a band of showers and possibly a rumble of thunder or two to develop, but nothing severe. Even small hail looks very unlikely if a small thunderstorm could develop as CAPE values are only around 100-250 J/kg and the freezing level should be around 7 kft. The challenge will be whether or not the system closes off or just swings through as an open wave. Without closing off the cooling aloft may not be enough to allow showers to develop.

Beyond the shower and very isolated thunder threat Wednesday will be strong winds shifting from the south to the west in the afternoon and evening. As they turn to the west, gusts in the evening and early overnight hours could be around 40 mph.

Later Wednesday night into Thursday night a quick upper level ridge moves through and mainly dry conditions are expected. The next wave will move into the area Friday into Friday night, with showers and isolated thunderstorms possible. Current trends deepen the low across ND Friday night into Saturday, then move east into Sunday. Overall, at least precipitationwise, this should not be a very impactful event. Shold remain all rain with only a very small threat for snow later Friday into Saturday as the system moves east. With the low wrapping up to the north and shifting east and northeast there will likely not be much cold air to wrap in behind. Also, even if this system can produce a couple of inches of rain, rivers are expected to remain within their banks.

AVIATION /18Z TAFS THROUGH 18Z MONDAY/

Issued at 1106 AM CST Sun Nov 15 2026

VFR through the period. Some periodic low level wind shear will be possible later tonight, with the better chances around KSUX. Otherwise gusty south winds will persist through the period.

FSD WATCHES/WARNINGS/ADVISORIES

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