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KEY MESSAGES

- Isolated to scattered severe thunderstorms expected over much of western and central North Dakota through this evening.

- Isolated to scattered severe thunderstorms possible over central into eastern North Dakota on Wednesday.

- Low to medium chances of showers and thunderstorms Thursday through the remainder of the week.

- Highs in the 70s and 80s through the workweek, warming into the 80s and lower 90s for the weekend.

DISCUSSION

Issued at 151 PM CDT Tue Jun 2 2026

Relatively well stacked low pressure is present over southern Saskatchewan. This low will very gradually slide eastward over the next couple days. During this timeframe, an associated very slow moving cold frontal boundary currently draped north to south over western North Dakota will slide eastward. This frontal boundary will likely become quasistationary, and possibly retrograde, at times. Showers and thunderstorms are present and will continue to frequently develop along and ahead of this frontal boundary.

High pressure over the Great Lakes region will continue advecting moisture from the Gulf of America into the Northern Plains. This added moisture, with boundary layer dewpoints in the mid 50s to low 60s will help produce a buoyant atmosphere. In addition, deep layer shear along and ahead of the front is generally progged at around 35 to 45 kts with a southwesterly component. Combined, this should produce the conditions for isolated to scattered severe thunderstorms this afternoon and evening. With the southwesterly component of the 0 to 6 km bulk shear vectors and a north to south frontal boundary, suspect clusters are the most likely thunderstorm mode along most of the front. Considering there is already a clusterish line of showers and thunderstorms along the frontal boundary, suspect a limited timeframe for any discrete cells to develop this afternoon. Though one has already developed near the Turtle Mountains as of this writing. This means that while there may be a window for golf ball size hail and an isolated tornado threat, this may wind up being a case where widespread marginal severe thunderstorms prevail overall. In addition, slow moving storm motions with the potential for training could lead to heavy rain and a localized flooding event.

Of note, a mesoanalyst will produce a mesoanalysis discussion within the next hour or two. This will provide even further details in regard to the severe weather threat based on the evolving severe weather environment. Depending on how the environment evolves, changes to the above threat expectations are not out of the question.

While there may be initial LLJ development this evening mainly over the eastern half of the state, it does not look to persist through the night. Therefore, while isolated to scattered showers and thunderstorms are likely to persist through at least parts of the area through tonight, the severe threat will likely wane rapidly as the sun sets, instability decreases, and capping increases. Still, a few strong storms are not entirely out of the question overnight.

For Wednesday, the aforementioned frontal boundary will continue to gradually shift eastward and as such, so will the severe threat. Therefore, concur with SPC that the highest severe potential for Wednesday will be in the south central (mainly east of Hwy 83) and in eastern North Dakota. The biggest threats will remain strong winds and large hail, though an isolated tornado threat could return mainly in the far southeast, including the southern James River Valley of ND.

Gulf moisture will be, at least temporarily, cut off behind the frontal boundary. However, a deepening low pressure over the Central Plains could bring the return of showers and thunderstorms mainly to southern North Dakota Thursday through Friday. The severe threat is favored to remain south for the most part at this time, though will keep an eye on that over the next couple days. Saturday is favored to remain mostly dry, after which periodic showers and thunderstorms are possible to start next week. CSU machine learning suggests at least low severe weather potential most days to start next week.

Slightly above average temperatures with highs in the mid 70s to low 80s are expected to continue through Friday. Well above average temperatures are then expected to return this weekend and are favored to continue into the middle of next week. Lows will start out mostly in the mid 40s to low 50s before increasing to the 50s to low 60s next week.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 1256 PM CDT Tue Jun 2 2026

A narrow line of showers and thunderstorms continues along a very slow moving cold frontal boundary over western North Dakota. These showers and thunderstorms are currently impacting the KMOT and KDIK terminals and will for at least another hour or two. The frontal boundary will very slowly drift eastward, perhaps stalling at times, through the TAF period. This will likely produce continuous showers and thunderstorms that should expand in coverage later this afternoon and through the night tonight. Isolated to scattered severe thunderstorms are expected this afternoon and evening, with the highest chances for severe weather being in central and southwestern North Dakota. Of note, to this point, winds have generally been fairly tame with these showers and thunderstorms. However, gusty and erratic winds are expected to develop as thunderstorm intensity increases this afternoon and evening.

BIS WATCHES/WARNINGS/ADVISORIES

None.