textproduct: Aberdeen

KEY MESSAGES

- Fog, with visibilities around 3 miles, may develop across far northeastern South Dakota and west central Minnesota early this morning.

- High temperatures Friday and Saturday will average 25 to 35 degrees above normal. Expect more seasonal temperatures from Sunday onward, with highs in the 40s to 50s through the start of the work week.

- Fire weather concerns remain over central South Dakota through Saturday, with afternoon gusts 15-25 mph Friday and Saturday and afternoon humidity nearing 20%. Watch for winds shifting out of a northerly direction and increasing with gusts around 30 mph late Saturday evening into Saturday night.

DISCUSSION

Issued at 147 AM CDT Fri Mar 20 2026

There is some signal for fog development early this morning, mainly over areas east of the James River. Strong RH recovery in addition to the recent snowmelt should leave the area primed for radiation fog to develop this morning. The wind provides a bit of a caveat however, up to 10-15 miles per hour out of the south. It seems to be a setup in which fog may develop where and/or when winds are light, but the uncertainty is too high to pinpoint the specifics any further than that.

The main concern for today and tomorrow will be the abnormal warmth and associated fire weather concerns. Compared to Thursday, looking at a bit of an 850mb temperature decrease (roughly a 2-4 degree Celsius difference across the board) this afternoon, so that will be reflected with a slight dip in high temperatures today. Still expecting temperatures into the 70s across most of the area (upper 60s over parts of northeastern South Dakota and western Minnesota), which will once again threaten record highs. Saturday's highs will be a bit warmer, ranging from the 70s over northeastern South Dakota and western Minnesota to 80s over central South Dakota. Once again record highs will be threatened, and confidence is higher on records being broken on Saturday over Friday (though both days reaching records is well within the realm of possibility).

With the abnormal warmth comes the concern for critical fire weather conditions Friday and Saturday. For Friday, both the wind and humidity will be on the margin of the threshold for Red Flag Warning criteria (gusts of 25 mph and 20% humidity respectively), but confidence is low at this point. Ensemble joint probabilities put the peak chances of reaching Red Flag criteria this afternoon at roughly 10-20% over portions of Dewey and Corson county. Winds Saturday are expected to fall short of Red Flag criteria in the afternoon (gusting 15-20 mph). Afternoon humidity will still drop below 20 percent over portions of Jones and Lyman counties, which could still lead to some elevated fire weather concerns.

Saturday night a cold front is set to pass through the forecast area, increasing winds overnight (gusts up to 30-35 mph) and veering them to the north. While the broad pattern of a ridge over the western CONUS will remain in place moving forward, temperatures behind this front will cool down to become near-normal (highs in the mid-40s) to just above normal through the start of next week. There will also be some chances for precipitation development along the front overnight Saturday into Sunday morning. An early look at soundings indicate rain will likely be the dominant precip type. The latest NBM probabilities show that areas along the South Dakota/North Dakota border have a 50-70% chance (decreasing moving further south) of seeing temperatures at or below freezing. All that to say freezing rain cannot be ruled out as a precip type early Sunday morning at this time. QPF expectations at this time are just a couple of hundredths, which coupled with a short period of time for temperatures to remain below freezing means that widespread impacts from ice accumulation appear unlikely at this time. Still, isolated slick spots may cause some minor travel concerns Sunday morning.

AVIATION /06Z TAFS THROUGH 06Z SATURDAY/

Issued at 1225 AM CDT Fri Mar 20 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are expected to continue at all sites over the next 24 hours. The only exception would be if fog potential early in the morning materializes. The latest guidance keeps the fog potential bottled up mainly north and east of this region, so pulled the fog mention out of the KATY TAF for now. Will re- introduce a TEMPO group for fog, though, if needed.

ABR WATCHES/WARNINGS/ADVISORIES

SD...None. MN...None.