textproduct: Bismarck

KEY MESSAGES

- Periods of rain or snow this evening transition to snow overnight. During the transition, there may be a period of freezing rain or sleet, mainly over the James River Valley region.

- Medium chances (40 to 60 percent) of seeing 2 or more inches of snow over a corridor from around Bismarck-Steele to around Harvey-Carrington. Locally higher amounts to 4 inches possible.

- Well below average temperatures Friday and Saturday, followed by temperatures trending warmer Sunday through the middle portions of next week.

UPDATE

Issued at 839 PM CDT Thu Apr 16 2026

We initially extended the SPS for the potential for a light glaze of ice in the northern James River Valley. After some of the short term models started arriving we ended up issuing a small, short duration Winter Weather Advisory from 10 PM this evening through 8 AM Friday morning.

The counties in the Advisory include Burleigh, Sheridan, Kidder, Wells, Foster and Stutsman. Foster and Stutsman were separated out for lesser snow/sleet accumulations (around an inch) and possibly more ice accumulation (light glaze to 0.05"). Burleigh, Kidder, Sheridan and Wells have seen an uptick in snow. Generally still 1-3 inches. However, a smaller area, currently eastern Burleigh and Sheridan into western Wells and Kidder counties could see 2-3 inches with locally higher amounts to around 4 inches.

Not sure about if we see these higher snowfall rates and if this is the area that eventually sees them. But we are pretty sure that if we do see rain change over to snow early enough tonight, there is enough very strong FG forcing to produce some higher snowfall rates over south central ND. The 12Z HREF was showing some low to moderate probabilities for snowfall rates greater than an inch an hour from around 06-10 UTC over south central ND. The WPC Snowband Probability Tracker was also hitting this area for higher snowfall rates during this same timeframe. Given the strong winds that are developing, the Blowing snow model is indicating some moderate impacts due to blowing snow when the heavy snow combines with the strong winds.

There are some limiting factors as well. Temperatures are a concern. It will be cold enough to turn to snow but surface and ground temperatures are warm enough that where we do not see the heavy snow rates, snow may be slow to accumulate. There is some potential for some banding, but given the lack of strong or even moderate synoptic scale forcing, it would probably be more unorganized. Lapse rates are steep to begin with, but taper pretty quickly as the the cold air builds over the area. Impacts could be significant for a while overnight, but the precipitation should be pretty much out of the area by around or shortly after 12 UTC. Portions of the I-94 and Highway 83 corridors could be impacted and with the real nice weather of late, we figured we would go ahead with an Advisory. The good news is that by the weekend the snow will be a distant memory.

UPDATE Issued at 538 PM CDT Thu Apr 16 2026

Cold front has pushed through all but the far southern James River Valley. Initially behind the front, a few mid and high clouds. Perhaps some shower activity was working it's way into northwest-west central ND. The main surge of precipitation will come tonight as the upper trough approaches. Shower activity continues to increase over western SD and eastern WY and this will continue to push northeast through the evening. For the early evening update we adjusted sky cover lower over a good portion of southwest and central ND. We also delayed the onset of the precip into the southwest, south central this evening. Otherwise no significant changes at this time.

DISCUSSION

Issued at 222 PM CDT Thu Apr 16 2026

Current surface analysis places low over south central North Dakota into north central South Dakota, with front stretching off to the west/southwest. High remains over northern Saskatchewan/Manitoba. Upper level analysis places ridge over the upper midwest with trough stretching from the lee of the Canadian Rockies towards the Great Basin, with low closing off over southern Alberta into northern Montana. This all is placing us in southwest flow. Over our area, a wide variety of temperatures exists with cold air wrapping in north and west of the low, and quite mild temperatures south and east. With the mild temperatures and rather low humidity over our southern James River Valley area, near critical fire weather conditions continue.

For tonight, trough continues its approach with cold air pouring into the area, while precipitation develops mainly along an area of notably elevated frontogenesis sliding through the area. Most locations start out as rain (exception being northern cold locations) with a transition to snow overnight. An area of concern continues to be over the James River Valley region where during that transition, forecast soundings suggest there may be a period of freezing rain or sleet. Have issued a Special Weather Statement to bring awareness to this, but given the question on how long this could last will hold off on an Advisory for now and will re-evaluate at a later time. As for snow amounts, still expect the higher amounts in line where the greatest and longer lasting area of frontogenesis is noted. Latest NBM guidance continues to show an area generally from Bismarck-Steele northeastward to Harvey-Carrington with around a 60 percent chance of seeing an inch or more, and around a 20-40 percent chance of seeing two inches. Some snow may linger over central North Dakota into Friday morning before departing to the east.

Notably colder air settles in for Friday, with highs only expected to climb into the upper 20s to the 30s. This colder air then shifts off to the east as ridging over the far western CONUS pushes east, resulting in a warming trend this weekend. By Monday, highs in the 60s to mid 70s are expected. Dry and mild conditions continue through mid-week before ensembles suggest a more active pattern bringing precipitation chances.

AVIATION /00Z TAFS THROUGH 00Z SATURDAY/

Issued at 538 PM CDT Thu Apr 16 2026

Widespread MVFR-IFR ceilings develop this evening into the overnight at all terminals, as a low pressure system brings rain and snow chances to the region, and possibly some freezing rain to the James River Valley including the KJMS terminal. Winds will also become northwesterly and gusty behind a cold front. Precipitation should exit eastern portions of the forecast area by mid to late Friday morning, with improving ceilings Friday afternoon. Winds will remain strong from the northwest through Friday afternoon.

BIS WATCHES/WARNINGS/ADVISORIES

Winter Weather Advisory until 8 AM CDT Friday for NDZ022-023- 025-035>037.