textproduct: Bismarck

KEY MESSAGES

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

- Low to medium chances (20 to 40 percent) of seeing 2 or more inches of snow over a corridor from around Bismarck-Steele to around Harvey-Carrington.

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

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 /18Z TAFS THROUGH 18Z FRIDAY/

Issued at 222 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. Conditions will slightly improve Friday morning.

BIS WATCHES/WARNINGS/ADVISORIES

None.