textproduct: Aberdeen

KEY MESSAGES

- Dry conditions persist on Saturday with elevated fire weather conditions across central SD in the afternoon.

- Storm chances increase Saturday night, continue through Sunday, followed by rain Monday.

- Marginal Risk (1 of 5) to Slight Risk (2 of 5) mostly focused across central and northeast South Dakota Sunday afternoon.

UPDATE

Issued at 750 PM CDT Fri May 15 2026

Southern segment of Red Flag Warning went away at 7 PM CDT. Remaining segment will be allowed to expire on time in about an hour from now at 9 PM CDT. Already beginning to see wind speeds decreasing and relative humidity steadying out/increasing slightly. The rest of the forecast for tonight remains on track. No other changes planned at this time.

UPDATE Issued at 618 PM CDT Fri May 15 2026

See below for an aviation forecast discussion for the 00Z TAFs.

DISCUSSION

Issued at 252 PM CDT Fri May 15 2026

Mostly sunny skies have dominated the areas today with just a few streaks of mid level clouds passing overhead. Temperatures have warms into the 70s to near 80 as dew point temperatures have stayed fairly steady in the upper 20s to mid 30s. This have led to afternoon RH percentages from the mid teens to low 20s. Gusty winds were initially sluggish to get going this morning but have since picked up to between 25-35 mph this afternoon. So, Red Flag Warning conditions have been met and that posted headline will remain in effect into early to mid evening. By sunset, gusty winds will have diminished across most of the forecast area and RH's will have recovered back to around 30-35 percent. Temps overnight look to fall to near normal with readings in the 40s.

Latest suite of guidance today indicates not much change in the overall upper flow pattern across the Northern Plains and Upper Midwest through the weekend into next week. Essentially zonal flow will persist through Saturday as an upper trough begins to dig into the western CONUS. This system will make a change in our dry pattern by the end of the weekend. As it digs farther east, southwest flow a lot develops across the Northern Plains and it's anticipated to send a few successive mid level waves of energy into our Sunday through Monday. This system is then progged to move out of the region by the middle of next week which looks to be followed by a weak and disorganized pattern during the latter half of next week.

Saturday will feature increasing mid level heights associated with shortwave ridging aloft leaving our area with another dry and warm day. Forecast sounding still indicate an increase in mid level moisture with a deep dry subcloud layer, so only anticipate passing clouds. Sfc high pressure will shift east across ND during the morning and into northwest MN in the afternoon. This will promote a east to southeast wind by later in the day into Saturday night. The pressure gradient does tighten back up across central SD during the afternoon as lee side cyclogenesis gets underway southwest of our region. Gusty southeast winds will develop and with RH values expected to fall to around 20 percent, elevated fire weather conditons will once again develop. Issued an SPS for now to highlight this message.

By late evening and early overnight Saturday night, pooling low to to mid level moisture will be advected northward into our region in a warm advection process. Expect showers and thunderstorms to develop late Saturday into early Sunday in our west and southwest and then track east to northeast through the morning hours with the first in that series of mid level shortwaves moving through. Elevated convection for the most part will accompany this with the potential for a few strong to perhaps severe storms with some risk for mainly hail. With daytime heating, an unstable air mass develops, especially across our far southern/eastern zones into the heart of southeast SD/southwest MN/northwest IA/northeast NE. A sharp instability gradient looks to develop just off to the southeast of our forecast area, moreso in southeast SD. Expect more robust convection to develop there but since we are on the northwest cusp of this, our southeast zones will have the best chance to see more active severe storms versus locales farther north and east. A Marginal to Slight Risk for severe weather has been posted by SPC for parts of central into northeast SD and west central MN with an Enhanced Risk just off to our southeast. Large hail will be the primary threat for our area but localized damaging winds will also be possible along with locally heavy rainfall. Rainfall amounts will be highly dependent on the strength and placement of the convection. Rainfall chances will continue into Monday as another mid level wave and sfc low tracks southeast of the area. This rainfall looks like it could linger into Monday night and early Tuesday before finally tapering off. Drier, cooler conditions set in Tuesday and Wednesday. In fact, below normal temperatures will be possible by this time frame. Progs for overnight lows will have to be watched more closely in the coming days as the potential remains for readings in the low to mid 30s increasing the potential for frost.

AVIATION /00Z TAFS THROUGH 00Z SUNDAY/

Issued at 618 PM CDT Fri May 15 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are forecast to continue at all terminals through this forecast cycle. West to northwest winds 10 to 20 knots with gusts to 30 knots are slowly beginning to diminish, and will continue to decrease throughout the next 2-4 hours. Late tonight into Saturday the wind direction becomes east to southeast. At KPIR/KMBG from late Saturday morning to late Saturday afternoon speeds begin to increase out of the southeast to 15 to 20 knots with gusts up to 30 knots.

ABR WATCHES/WARNINGS/ADVISORIES

SD...Red Flag Warning until 9 PM CDT /8 PM MDT/ this evening for SDZ003>011-015>017-021. MN...Red Flag Warning until 9 PM CDT this evening for MNZ039-046.