textproduct: Aberdeen

KEY MESSAGES

- High temperatures will be in the 40s and 50s through next Tuesday, which is around 5 to 10 degrees above normal. Warmest temperatures will be this weekend.

- Turning markedly colder starting next Wednesday, as temperatures tumble into the teens at night and 20s and 30s during the day.

UPDATE

Issued at 656 PM CST Wed Nov 19 2025

Just a quick update to add dense fog to two areas, one up east of Mobridge to Eureka, the other just west/south of Pierre into Murdo and parts of I-90 in Jones/Lyman. These are fairly small areas overall, and separated by 40 miles (Sully/Hughes counties) so at this time considered too localized for a dense fog advisory despite visibility down to 1/4 mile on webcams. Additionally, its fairly rare to have have dense fog on a northwest component. Expect it will transition to the southeast with the mean flow this evening/overnight.

UPDATE Issued at 530 PM CST Wed Nov 19 2025

See below for an update to the aviation discussion...

DISCUSSION

Issued at 139 PM CST Wed Nov 19 2025

At 1 PM CST, skies were a mix of sun (central South Dakota) and clouds (north central/northeast South Dakota and west central Minnesota). Been mixing out low clouds and patches of (dense at times) fog today underneath what had been a blanket of earlier mid/high clouds. Temperatures have been warming out of the 30s through the 40s, with a few locations (central South Dakota) starting to run up into the 50s. Except for the far western (west river) counties where a west-northwest wind has developed early this afternoon, winds continue out of the south around 10 to 20 mph with some occasionally higher gusts.

The wind-shift responsible for turning the wind around to a west- northwest direction will make it's way over into Minnesota during the evening hours, with an area of surface high pressure building into the region behind it overnight. This high pressure is forecast to stick around Thursday and Thursday night, yielding dry, light wind conditions, and temperatures a little bit cooler for Thursday, with highs only expected in the mid 40s to around 50 degrees (about 5 to 10 degrees cooler than today's expected highs, but still roughly 5 degrees above climo normals for mid-November).

The long term period is a split flow pattern, where the northern branch jet-stream is a low amplitude upper level ridge over the northwest/north central CONUS from Friday through next Monday. There is general agreement amongst model camps for a longwave trof to work through the northern branch jet-stream and knock the ridge down across southern Canada and the northern plains from Monday night through the end of the forecast period. This upper level trof is expected to drop and drag a potent cold front through the CWA somewhere between 12Z Tuesday and 12Z Wednesday. With an upper level closed low drifting out of the desert southwest into the deep south Saturday through Monday, there is some doubt over whether any Gulf moisture will make it past the southern U.S. system, and be available to generate WAA-zone forced light precipitation (over this CWA) with this northern branch system Tuesday/Wednesday. Suffice it to say, the change in airmasses with this cold fropa next week will be quite noticeable. Instead of high temperatures being in the 40s and 50s, highs will only be in the 20s and 30s starting next Wednesday. Low temperatures are expected to transition from 20s and 30s down into the teens (possibly single digits) above zero.

AVIATION /00Z TAFS THROUGH 00Z FRIDAY/

Issued at 530 PM CST Wed Nov 19 2025

Terminals KABR,KATY,KPIR,KMBG

We have one layer of MVFR/IFR stratus that ensconces KABR/KATY, a smaller area of IFR CIGS out by KPIR, and a third small area of IFR CIGS/Fog by KMBG, while just to the northwest of KMBG a layer of MVFR stratus. As we proceed through the TAF period, the low CIGS impacting KABR/KATY will shift to the north. Then the stuff in North Dakota will take over for KMBG/KPIR. That then continues east to eventually impact KABR/KATY. The time between status layers for KABR may be very short indeed, but a little longer for KATY which will have a discernible period of VFR conditions. This low moisture is expected to stick around into the day Thursday.

ABR WATCHES/WARNINGS/ADVISORIES

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