textproduct: Aberdeen

KEY MESSAGES

- On Wednesday, winds out of the south will gust 35 to 45 mph and relative humidity will fall into the 15 to 30 percent range. The strong winds and warm/dry conditions will combine to create very high to extreme grassland fire danger index values. Fire Weather headlines are in place for this.

- There is a 35-75 percent chance of showers and thunderstorms Wednesday night into Thursday, mainly throughout central and north central South Dakota.

- Record or near record warm temperatures in the upper 80s to lower 90s are expected Wednesday.

- Strong sustained west winds 25 to 35 mph with gusts up to 45 mph are expected on Thursday.

DISCUSSION

Issued at 1147 AM CDT Tue Apr 21 2026

At 11 AM CDT, skies are sunny and temperatures are warming through the 50s and 60s. Winds are light and variable becoming east or southeast generally 5 to 15 mph.

Northwest flow aloft continues for another day and a half. Low level jet southerly winds still forecast to develop tonight and persist through Wednesday night in response to the strength of the low level WAA progged to develop tonight through Wednesday evening. Right now it does not appear as though Gulf moisture will make it this far north by Wednesday. RH's and sustained winds/gusts, combined with how warm it is forecast to get has yielded fire weather headlines for Wednesday afternoon. Right now temperatures warming into the 80s to low 90s with dewpoints up into the 30s and 40s are causing afternoon minimum rh's to fall well below 20-25 percent over much of the western half of the CWA. And, strong southerly winds 20 to 35 mph with gusts to 40-45 mph are forecast.

The closed upper low circulation now just off the west coast is still progged to make its way over into the central/northern plains region from late in the day Wednesday through Thursday. Still seeing a decent mid-level vort-lobe working over the CWA by the middle of Thursday. Out ahead of this vort-max, the combination of dynamic and thermodynamic factors for forcing, lift, and moisture/instability all supports the potential for a period of showers and thunderstorms heading into Wednesday night mainly across portions of central/north central South Dakota (35 to 75 percent chance of measurable precipitation), spreading into portions of northeast South Dakota/west central Minnesota by late Thursday morning. Beyond that, the forecast pretty much dries out for a couple of days as the upper circulation sets up to the north-northwest of the CWA. There is some general consensus that another chance for precipitation should be lining up for Sunday through Monday.

Still looks rather windy out of the west/northwest on Thursday across north central South Dakota, but the latest iteration of model progs is really backing off in terms of sustained/persistent strong westerlies Friday into Saturday. Also, models appear to be trying to retrograde the upper low slightly westward/northward over Canada during the weekend, which may allow for the Sunday/Monday precipitation potential to extend a bit further north toward this CWA than previous model runs have been placing it. This, in turn, is introducing some slight modifications (warming) to the temperature forecast from Friday through Monday of next week.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 1147 AM CDT Tue Apr 21 2026

Terminals KABR,KATY,KPIR,KMBG

Good VFR conditions are forecast through the TAF period, with strong southerly winds 15 to 30 knots with gusts to 40 knots developing later tonight and continuing through Wedneday. There could be a few hours of low level wind shear potential overnight at the KMBG terminal.

ABR WATCHES/WARNINGS/ADVISORIES

SD...Fire Weather Watch from Wednesday afternoon through Wednesday evening for SDZ007-008-011. Red Flag Warning from 1 PM to 8 PM CDT Wednesday for SDZ019>023. Fire Weather Watch from Wednesday afternoon through Wednesday evening for SDZ003>006-009-010. Red Flag Warning from 11 AM CDT /10 AM MDT/ to 8 PM CDT /7 PM MDT/ Wednesday for SDZ015>018-033>037-045-048-051. MN...Fire Weather Watch from Wednesday afternoon through Wednesday evening for MNZ039. Red Flag Warning from 1 PM to 8 PM CDT Wednesday for MNZ046.