textproduct: Aberdeen

KEY MESSAGES

- Into early this evening, southerly winds gusting up to 35 to 50 mph will combine with relative humidity values of 10 to 25 percent to create Red Flag conditions today. If a fire were to ignite, it could become difficult to control or suppress.

- Showers and thunderstorms develop across central SD this evening and move east overnight. There is a marginal risk (level 1 of 5) for severe storms, mainly west of the Prairie Coteau, with the potential for wind gusts of 60 to 70 mph.

- Strong sustained west winds 25 to 35 mph with gusts 40 to 50 mph are expected Thursday mainly over central SD. High to very high grassland fire danger is expected Thursday afternoon as relative humidity falls to 20 to 40 percent.

UPDATE

Issued at 541 PM CDT Wed Apr 22 2026

Strong winds, low relative humidity, and dry grasses has resulted in a few fire starts this afternoon. Outside of thunderstorms, winds will remain out of the south into the late evening to overnight hours. While winds diminish 10-20mph over central SD (from the current gusts of 40-50mph), they will remain near the current speeds over the higher elevations of northeastern SD. We're continuing to watch showers and a few thunderstorms. We already had a weak thunderstorm bring gusts of 62 mph in McPherson County at 435 PM. Strong winds remain the primary concern this evening into the early overnight hours.

DISCUSSION

Issued at 534 PM CDT Wed Apr 22 2026

Southerly winds are increasing south of a warm front stretching from Fort Pierre to Watertown and creeping north this afternoon. Red Flag Warning remains in effect for the winds that will combine with near record highs and a very dry air mass to create very high to extreme grassland fire danger.

Shortwave energy ejecting out of an upper trough over the Rockies along with 45 to 50 kt llj will help generate convection this evening starting in central SD around 0z. This will mostly be ahead of and with a trailing cold front associated with the sfc low in MT/ND. The marginal risk (1 out of 5) for severe storms has expanded eastward to include all areas west of the Coteau. The main threat with the steep lapse rates and enhanced DCAPE will be strong winds with gusts of 60 to 70 mph (strongest in any short-lived downbursts). The drier airmass will keep hail to a minimum, but can't rule out an isolated cell or two capable of producing 1 inch hail. No wetting rains are expected with this system through Thursday, so will need to look closely at the fire weather threat Thursday, as well. Behind the convection/cold front more dry air moves in with westerly winds gusting as high as 50 mph across central SD by afternoon as the upper trough sweeps through with reinforcing caa. Will likely need a wind advisory for Thursday, but will push that off to the mid shift given the current headlines in place for today and potential for fire considerations for tomorrow.

The sfc low shunts north Thursday night. Another trough sets up early Friday, but models are not in good agreement about precip with the trough off the Black Hills or with the Colorado low moving into the plains late Friday. Global models seem to keep precip farther south even though hi-res puts the initial activity early Friday morning into central SD. With upper troughing digging into the northern Plains Thursday into next week, high temperatures will be below normal, topping out in the 50s through the middle of next week.

AVIATION /00Z TAFS THROUGH 00Z FRIDAY/

Issued at 541 PM CDT Wed Apr 22 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions with high based clouds are starting us off. However, there are isolated showers and a few thunderstorms that will be nearing PIR/MBG this evening. We will continue to monitor the latest trends and update to add thunderstorms if needed. Wind gusts will only diminish to 25-35kts overnight before rising again into the 35-45kt range. The strongest winds over the period are expected at PIR/MBG.

ABR WATCHES/WARNINGS/ADVISORIES

SD...Red Flag Warning until 8 PM CDT /7 PM MDT/ this evening for SDZ003>011-015>023-033>037-045-048-051. MN...Red Flag Warning until 8 PM CDT this evening for MNZ039-046.