textproduct: Aberdeen

KEY MESSAGES

- Another round of rain arrives Friday afternoon into Saturday morning. There is a 40-60% chance to see a quarter of an inch or more through Saturday morning.

- Expect temperatures near normal for the next few days, with highs in the upper 60s to low 70s. Signs point towards a cooldown next week.

UPDATE

Issued at 1226 PM CDT Thu Sep 24 2026

Aviation discussion below has been updated in accordance with the 18Z TAF issuance.

UPDATE Issued at 921 AM CDT Thu Sep 24 2026

This morning, some lingering showers are in place over northeastern South Dakota and western Minnesota. The threat for lightning is effectively over at this point, and showers are expected to continue pushing eastward, exiting the area in the next couple of hours. Meanwhile, some patchy fog was in place earlier this morning, causing visiblity reductions as low as a mile at times. Observations indicate that the fog is in the process of burning off this morning, but some minor visibility reductions may still be possible over the next hour.

UPDATE Issued at 639 AM CDT Thu Sep 24 2026

The aviation discussion has been updated for the 12Z TAFS.

DISCUSSION

Issued at 211 AM CDT Thu Sep 24 2026

As of 06Z, the shortwave is currently positioned over northwestern SD through ND/Canada with winds out of southwest through 850mb and southerly/southeasterly winds at the surface. With this flow lots of moisture is being pulled in from the south and southwestern US (seen on water vapor imagery) in thanks to a 30kt LLJ over much of the CWA as the surface trough currently extends just west of the CWA. This has led to better coverage and formation of scattered rain showers tracking northeast along and just east of the Mo River with additional rain moving in from southern SD/NE. 500 j/kg of MUCAPE and 25-30kts of bulk shear is producing weak embedded thunderstorms we well. Through 12Z CAMs really indicate this shortwave energy induced rain across NE/KS continuing to merge with the rain over the Northern Plains to produce additional development and better coverage of the scattered rain, and potentially weak thunderstorms, east of the James River into MN. The last of precip is forecast to exit far eastern SD/MN by the midday or early afternoon as CAMs overall agree on this. A few of the CAMS do indicate lingering spotty showers possible Coteau eastward 18Z through tonight. Probability of QPF (or additional QPF)>0.25" (starting at 06Z) is 60- 95% James Valley and eastward, highest along and east of I29. Prob for a half inch is 60-80% along and east of I29. Any stronger rain showers or storms could produce locally higher QPF.

Otherwise, dry air aloft moves in behind the system and will continue to spread eastward across the CWA with the driest air along and west of the MO River by this evening/overnight as the Northern Plains remains under this broad ridge and mid level high moves in over the region. Surface winds will be out of the southeast/east over central SD and southeast over northeastern SD/MN. With ongoing low level moisture and cloud cover hanging around, this could result in low stratus/drizzle/fog late tonight through Friday morning as NAM/EC soundings indicate this classic drizzle setup with some omega at the surface to 850 and dry air aloft. So fog and drizzle may need to be added in closer to time if confidence increases.

We continue with this shortwave train as more energy moves in from the south combining with a stronger negatively tilted shortwave moving in from the southwest (per an ongoing trough hanging over the PacNW). This neg tilted shortwave will track northeast across the region Friday through Saturday. Southeasterly flow at low levels will pull in moisture resulting in another round of rain. As of now, pops will increase south to north across the CWA Friday afternoon and evening with the bulk of the precip occurring Friday night through Saturday morning (mainly east of Mo River) with the help of strengthening LLJ. Latest NBM pops range from 40-70%, highest James Valley and eastward. Rain will diminish west to east through late Saturday afternoon. Probability of 24 QPF>0.25 ending Saturday evening is 40-60% James Valley and eastward. Still a bit of a difference between models QPF wise with the 25-75th spread of 0.3 to 0.6", highest over eastern and southeastern CWA.

Dry conditions for Sunday but we will continue in this active weather pattern as the trough that has been hanging out over the PacNW will track northeast into Canada with another trough developing over the western CONUS Monday and track eastward and over the central/southern CONUS Tuesday/Wednesday. Still quite the difference between the Clusters on location timing and intensity and its surface low that is forecast to develop over the Northern Rockies and track across the Northern Plains Monday/Tuesday bringing the return of rain.

AVIATION /18Z TAFS THROUGH 18Z FRIDAY/

Issued at 1226 PM CDT Thu Sep 24 2026

Terminals KABR,KATY,KPIR,KMBG

MVFR to IFR conditions remain over much of the region this afternoon, with the cloud deck responsible for the category reductions beginning to clear out over central South Dakota. Otherwise, there is some lingering drizzle over parts of northeastern South Dakota and western Minnesota, which may cause some reductions in visibility down to MVFR or IFR status through this evening at KATY.

The main focus in the aviation forecast is the potential for fog development late tonight into early Friday morning. Light winds and high near-surface moisture provide a prime environment for widespread fog to develop, particularly over north central and northeastern South Dakota. Visibility down to IFR levels will be possible, and perhaps even LIFR at times. Confidence is a bit lower on the extent of coverage further south, but the expectation is that most of the forecast area will see at least some visibility reduction. Fog is generally expected to dissipate by mid-morning.

ABR WATCHES/WARNINGS/ADVISORIES

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