textproduct: Bismarck

KEY MESSAGES

- Low to medium chances (20 to 40 percent) for thunderstorms late this afternoon into this evening. Some may become severe over western and south central North Dakota.

- Daily chances for showers and thunderstorms continue through the upcoming work week.

- Near to a bit below average temperatures through the first part of the week, then a cooling trend for the later part of the week.

DISCUSSION

Issued at 326 AM CDT Sun Aug 9 2026

Current surface analysis places low over northeast Colorado/western Nebraska with inverted trough stretching through central South Dakota into south central North Dakota, while high remains over Alberta into Saskatchewan. Upper level analysis places broad high over the southwestern CONUS with modest ridging to the north, while low remains over northeast Manitoba/northern Ontario. Over our area, convection remains to the south and east of the James River Valley ahead of the aforementioned surface trough.

For today, quiet weather starts the day as aforementioned inverted trough pushes off to the east. As we get into the afternoon and evening hours, another surface low deepens and pushes through northern Wyoming into southwest South Dakota and western Wyoming, while an inverted trough pushes into northwest South Dakota and western North Dakota. In the meantime, a pair of modest short waves slide through west/northwest flow into our area. This will bring the next chances for showers/thunderstorms to western and central North Dakota late today into tonight. In the meantime, elevated deep layer shear is noted during this period, with 0-6km values around 45-55kts. The question is how much moisture can be advected in ahead of the inverted trough, and thus how elevated the instability may be. With that said, given the strong shear and the elements present to produce convection, the severe threat will be present going through the evening.

West-northwest flow pattern remains active our our area through mid-week bringing a daily chance for showers and thunderstorms, with clusters suggesting an upper flow shift to more westerly or even a bit southwesterly as we get later in the week, which would continue precipitation chances. Temperatures remain near to a bit below average through mid-week, cooling below average for later in the week.

AVIATION /06Z TAFS THROUGH 06Z MONDAY/

Issued at 102 AM CDT Sun Aug 9 2026

Isolated thunderstorms remain possible over far south central North Dakota into the James River Valley overnight. Later Sunday afternoon and Sunday evening, isolated to scattered thunderstorm chances spread west to east over western and central North Dakota. In addition, wildfire smoke aloft will occasionally reach the surface, possibly bringing brief periods of MVFR visibility.

BIS WATCHES/WARNINGS/ADVISORIES

None.