textproduct: Aberdeen

KEY MESSAGES

- Warming trend continues through Thursday. Highs in the upper 70s to mid 80s Thursday (15 to 30 degrees above normal).

- The combination of warm temperatures and southerly winds of 25 to 30 miles per hour result in High to Very High Grassland Fire Danger Thursday. A Red Flag Warning is in effect for Thursday over central and northeastern South Dakota as well as parts of north central South Dakota. A Fire Weather Watch has been issued for west central Minnesota as well.

- A cold front will move through the area Thursday night, leading to below normal temperatures (highs in the 40s) and precipitation Thursday night into Friday. Precipitation starts out as rain Thursday night before transitioning to snow as colder air moves in. A couple tenths of snow accumulation on grassy surfaces is expected.

UPDATE

Issued at 622 PM CDT Wed Apr 15 2026

The forecast remains on track this evening. No major changes are planned.

DISCUSSION

Issued at 230 PM CDT Wed Apr 15 2026

Warming trend continues today with highs widely on track to hit the mid-70s, about 15 degrees above normal for this time of year. Other than some fair weather cumulus over eastern South Dakota and into western Minnesota, clear skies and light winds will continue through the rest of this afternoon and evening.

Temperatures increase further on Thursday, with 850mb temperatures of 15-19 degrees Celsius, well above the 90th percentile for this time of year. This translates to highs over much of the area (excluding north central South Dakota due to a cold front discussed below) reaching the upper 70s to low 80s. Despite these highs 20-25 degrees above normal, no climate sites are expected to hit record highs. Southerly winds are expected to increase Thursday as well due to the incoming low pressure center and resultant tightening of the pressure gradient. Gusts up to 30 knots are expected across the forecast area by the afternoon. Due to the widespread warmth dropping humidity to 15 to 25 percent as well as the gusty winds, the Fire Weather Watch has been upgraded to a Red Flag Warning across central and northeastern South Dakota, as well as part of north central South Dakota. A Fire Weather Watch has also been issued for Big Stone and Traverse counties in western Minnesota, as confidence in reaching Red Flag criteria is slightly lower over that area.

A longwave trough will move east over the next couple of days, supporting a low pressure center and a cold front influencing the Northern Great Plains beginning Thursday. In the afternoon and evening on Thursday, the cold front will begin moving across the forecast area, which is an acceleration in timing from previous forecasts. Precipitation is expected to develop slightly behind the front, with the lift coming from divergence aloft in the exit region of the trough. At the moment, precipitation chances remain mainly over north central South Dakota. Ensemble probability of reaching a tenth of an inch of liquid equivalent extends in a gradient across the forecast area, up to 60 percent in Corson County and decreasing moving to the southeast. As cold air settles in behind frontal passage, a transition from the initial precipitation type of rain will transition to snow. The majority of the precipitation is expected to fall before the warm nose cools below freezing and allows for snow to reach the surface. Therefore, only a couple of tenths of an inch of snow are expected at the most. Ground temperatures will be quite warm still, so expecting most of the snow to melt on impact, with the possible exception of grassy surfaces.

Post-frontal northerly winds will also pick up, gusting to 30-40 miles per hour across the area Friday. Similar speeds will be present Saturday over northeastern South Dakota and western Minnesota, with a slight dip over central and north central South Dakota (gusts topping out at 30 miles per hour in that area). NBM probabilities have backed down a bit, now sitting at less than a 20 percent chance of reaching Wind Advisory criteria both afternoons. Upper-level support Friday and Saturday afternoons will remain below 35-40 knots, so concern for any sort of Wind Advisory potential is waning.

Looking ahead to next week, an upper-level ridge will build into the area, heralding the return of above normal temperatures to the Northern Great Plains. Current ensemble means put highs in the mid to upper 70s while the ridge is overhead, roughly 10-20 degrees above normal. Ensemble cluster then show a fair degree of confidence on another trough developing over the western CONUS, placing the Aberdeen forecast area into the left exit region and possibly bringing chances for precipitation. There is still quite a large timing disparity on when exactly this system is set to arrive, so sometime mid-week is the best depiction at this time range.

AVIATION /00Z TAFS THROUGH 00Z FRIDAY/

Issued at 622 PM CDT Wed Apr 15 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are expected through Thursday afternoon. Southerly winds increase Thursday morning with gusts to around 25 kts then shift to the northwest toward the end of the period as a cold front moves through.

ABR WATCHES/WARNINGS/ADVISORIES

SD...Red Flag Warning from 11 AM CDT /10 AM MDT/ to 8 PM CDT /7 PM MDT/ Thursday for SDZ005>008-010-011-016>023-033>037-045- 048-051.

MN...Fire Weather Watch from Thursday morning through Thursday evening for MNZ039-046.