textproduct: Aberdeen

KEY MESSAGES

- Highs in the 60s and 70s Saturday through Tuesday will be 15 to 25 degrees above normal for this time of year.

- On Saturday, winds will be out of a southerly direction gusting 35 to 45 mph. Combined with the dry air and dry fuels, very high Grassland Fire Danger Index values are forecast Saturday for portions of south central to northeastern South Dakota and west central Minnesota, with extreme possibly over east central South Dakota.

UPDATE

Issued at 626 PM CDT Thu Mar 26 2026

Updated for 00Z Aviation discussion below.

UPDATE Issued at 547 PM CDT Thu Mar 26 2026

Minor updates to the forecast for tonight, largely to capture latest trends in the higher res models for winds/snow behind the cold front. Looks to be a 3-6hr period of increased winds behind the front overnight tonight, primarily over central SD. Low level lapse rates steepen up after the front and allow for mixing down the 925mb winds around 25-30kts from northwest to southeast. Tried to time the peak winds initially behind the front, then slowly tapered them off into Fri morning. Similar theme for PoPs/Snow over northeast SD and west central MN. While the initial push of snow from MT and western ND this evening should diminish as it moves into north central SD, another area associated with the shortwave and steepening LRs behind the front may be enough to produce shallow snow showers. While CAMs are mixed on it occurring, when we've seen past situations like this with steep LRs and moisture getting into the DGZ, we'll usually get a few snow showers. Thus, added in some slight chance PoPs and flurries to account for it.

DISCUSSION

Issued at 304 PM CDT Thu Mar 26 2026

A cold day continues, with temperatures steady to falling through the day under thick clouds. At 20Z, the ABR 88D radar shows reflectivity values stretching from north central SD through just south of Aberdeen and southern Roberts county into west central MN. This band has produced light snow with visibility down to 1.5 miles over Mobridge when it passed, and has brought a wintry mix of light snow and freezing rain to Milbank. The most pronounced/productive portions of this line are over north central SD and west central MN. The trend is for this time to continue its slow southern movement, with a diminishing trend. We'll need to continue to monitor the southern progression, as an increase in chances of precipitation may be warranted.

Temperatures will fall into the teens to low 20s tonight, and still only rebound into the 30s and 40s Friday. Despite the cold air, drier air will move in, with afternoon relative humidity values falling into the 30 to 35 percent range. Winds will be much lighter Friday, with gusts on the order of 20-25 mph.

Relative humidity recovery Friday night/Saturday morning will be in the 30 to 60 percent range (lowest over central SD). Expect winds to increase out of the south overnight with a 40-60kt low level jet. While winds will diminish quickly over north central SD in the afternoon, the winds will hold on longest over south central to northeastern SD (especially over the eastern downslope areas of the Prairie Coteau). The southerly direction gusting 35 to 45 mph, and minimum afternoon humidity will fall between 15 and 25 percent. The strongest winds will extend across south central to northeastern South Dakota during the morning to early afternoon hours, before diminishing. Very high Grassland Fire Danger Index values are forecast Saturday for portions of south central to northeastern South Dakota and west central Minnesota, with extreme possibly over east central South Dakota. A Fire Weather Watch has been issued Saturday for our 5 southeastern most counties, where the strongest winds align with dry air/relative humidity less than 25%.

While we do have the mention of precipitation returning Tuesday- tuesday night, it is only around a 20 percent chance. Cooler air, and at least a 30% chance of precipitation will return for Wednesday and Thursday.

AVIATION /00Z TAFS THROUGH 00Z SATURDAY/

Issued at 626 PM CDT Thu Mar 26 2026

Terminals KABR,KATY,KPIR,KMBG

Lingering MVFR ceilings will remain for at least a few more hours at KABR/KATY, although do have concern that they even leave at KATY tonight. Otherwise, the rest of the forecast is tied to an upper level disturbance and cold front that will moves through overnight tonight. This may bring snow showers to KMBG, with the line currently moving through western ND. Not too much south into SD, but latest trends and hi-res models point towards it approaching KMBG and potentially diminishing before reaching the site. Did add a PROB30 to account for that potential. As the front moves through overnight, expect northwest winds to pick up and gust to 25-30kts over central SD and potentially into KABR through through the first half of the morning before gradually diminishing. Also, could see some snow showers behind the front in northeast SD late tonight into Friday morning. Currently don't have them reaching KABR/KATY, but am seeing some trends farther to the southwest, so may need to add a PROB30 for it with the 06Z issuance.

ABR WATCHES/WARNINGS/ADVISORIES

SD...Fire Weather Watch from Saturday morning through Saturday evening for SDZ019>023.

MN...None.