textproduct: Bismarck

KEY MESSAGES

- Another round of isolated to scattered severe thunderstorms is possible this evening into Monday.

- Near to above average temperatures are favored this weekend through the middle of next week, potentially warming to well above average heading into the Fourth of July holiday weekend.

UPDATE

Issued at 644 AM CDT Sun Jun 28 2026

A little patchy fog has developed over parts of western and central North Dakota, with the most obvious reductions in visibility currently in the north central. Fog should dissipate rapidly this morning as the sun continues to rise. Otherwise, reduced PoPs in central ND through much of the day today to better match current radar and model forecast trends.

DISCUSSION

Issued at 323 AM CDT Sun Jun 28 2026

A line of thunderstorms has exited the forecast area (western through central North Dakota). As such, the severe weather threat has ended across the CWA early this morning.

Large upper low currently over eastern Montana/southern Saskatchewan will remain quasi-stationary as it wobbles around Montana, southern Saskatchewan, and southern Alberta through Monday. After which models are in fair agreement that it will push off east towards Manitoba before becoming quasi-stationary again Monday night through Tuesday. After Tuesday, it will finally move off to the east during the latter half of the week. Bottom line is that this will result in periodic showers and thunderstorms through the start of the workweek, some of which may be severe.

Today will be mostly dry, though a few showers and thunderstorms could develop mainly in the far northwest this afternoon. Severe weather potentially returns this evening, and especially overnight into Monday morning. Surface low pressure moving from central Nebraska through eastern South Dakota will advect Gulf moisture into much of the eastern half of the state. Another potentially strong shortwave off aforementioned upper low and 500 mb vort max could help force nocturnal supercells, which would likely be elevated in nature. As such, the primary threat will be very large hail, which could be two inches or greater in diameter. The highest probability for very large hail will be in south central and parts of southeastern North Dakota.

A conditional severe thunderstorm threat is possible again Monday afternoon and evening, however, that will heavily depend on how morning convection plays out and what the environment looks like later in the day. Other than a few stray showers or thunderstorms, Tuesday through Tuesday night then looks mostly dry. After which, periodic showers and thunderstorms are possible through the weekend as embedded shortwaves within southwesterly to westerly flow aloft push through the region. Though some uncertainty remains, deterministic models are in fair agreement that direct Gulf moisture will frequently be cut off during most, though not necessarily during all time periods. How this evolves will highly impact severe potential during the Holiday weekend, as well as just how high heat indices become.

High temperatures will gradually increase through the week as a ridge builds over the Northern Plains and Midwest, with the current NBM favoring the warmest day overall as July 3rd. This includes the warmest ambient and apparent temperatures. Latest NBM does show a potential slight cooling trend this weekend as an upper low breaks down ridging over the Northern Plains. However, moderate uncertainty remains in regard to the forecast for the holiday weekend.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 644 AM CDT Sun Jun 28 2026

Patchy fog is present in parts of western and central ND early this morning, though should rapidly dissipate over the next couple hours. Scattered showers, perhaps with a few rumbles of thunder, are possible in the northwest this morning and afternoon. Otherwise, a mostly dry day is expected today. Shower and thunderstorm chances then return to much of the state this evening and through the night. A few storms may be severe. IFR/MVFR ceilings may accompany these showers and thunderstorms mainly east of Highway 83 late tonight.

BIS WATCHES/WARNINGS/ADVISORIES

None.