textproduct: Bismarck

KEY MESSAGES

- Marginal (level 1 out of 5) to Slight Risk (level 2 out of 5) of severe weather over much of western and central North Dakota today into tonight.

- Marginal (level 1 out of 5 to Slight Risk (level 2 out of 5) of severe weather over central and 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.

UPDATE

Issued at 639 AM CDT Tue Jun 2 2026

We updated pops based on latest radar and added some patchy fog along and east of the Highway 83 corridor. Otherwise no changes to the going forecast.

DISCUSSION

Issued at 231 AM CDT Tue Jun 2 2026

The main forecast issue today will be the threat for severe convection today into tonight and again on Wednesday. An upper level low situated over far southwest Saskatchewan early this morning will move very slowly northeast through Wednesday morning, then will pick up a little speed Wednesday as it tracks east from Saskatchewan into Manitoba by Thursday morning. This will provide a risk for strong to severe thunderstorms over all of western and central North Dakota today, with the threat for strong to severe storms shifting into central and eastern ND on Wednesday.

Currently, scattered showers and embedded thunderstorms were lifting northeast across far east central Montana and into western North Dakota. Increasing CIN through the early morning hours should keep the threat for severe storms low, but with effective shear increasing over western ND through this same timeframe, a low threat for severe storms remains.

As we go through the morning hours and into this afternoon, the atmosphere is expected to destabilize along and ahead of weak cold front over western/central North Dakota. With the upper low position over southern Saskatchewan, most of western and central ND will be in a favorable position for strong shear of 40 to 55 knots this afternoon into this evening. The position of the aforementioned front is roughly NNE-SSW across central ND by mid afternoon. Bulk shear is increasing and is southwest to northeast across central ND in this same general timeframe. The orientation of the shear with the boundary looks to be neither parallel nor perpendicular, but does look to be more parallel than perpendicular. This would suggest a messy mixed mode and the HREF paintball of Updraft Helicity does indicate a mix of mostly short tracks, but also some longer tracks within the overall cluster. We will message the same threats as yesterday, large hail to golfball size, winds to 70 mph and an isolated tornado threat. These storms will also have the potential for very heavy rainfall. The tornado threat looks to be highest over southwest ND, closest to a surface low forecast to develop over western South Dakota. However, the RAP STP shows values of 1-3 along the aforementioned frontal boundary across central ND, with a local max over the north central late this afternoon. With more of a parallel than perpendicular component of shear, there may some higher wind gusts in any bowing segments, this kept the 70 mph wind threat. Large hail to the size of golf balls will also be a threat for any supercell storm.

The HREF UH paintballs also shows a max in the north central early to mid afternoon, then moving into or developing in the southwest/south central late afternoon into early this evening. There is then definitely a downtick in activity as we approach midnight tonight, but there may still be convection that lingers over the southwest/south central overnight and into Wednesday morning. Then on Wednesday we repeat the severe threat over central and into eastern ND as convection develops/strengthens over central ND and moves into the eastern portion of the state. All threats, large hail, strong damaging winds, heavy rain and isolated tornados will all be on the table, it will just be a question of how overnight and early morning convection (or the lack thereof) evolves early Wednesday. It does look like the threat Tuesday will be mainly during the day and into the early evening over our neck of the woods, but will have to see how things evolve today into early Wednesday morning before we get a better idea.

The threat for severe convection does look to wane a bit late in the workweek with the CSU machine learning page keeping the threat for severe storms limited to the far south, or even south of the forecast area. The threat does increase a bit by the weekend as we warm into the 80s and lower 90s by Saturday and especially Sunday. We become quite unstable each day, but the shear appears marginal at this time. But with the strong instability, there looks to be at least a small threat of severe storms over the weekend and into early next week.

AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/

Issued at 639 AM CDT Tue Jun 2 2026

Scattered showers with embedded thunderstorms over western and central ND this morning will propagate slowly east. Expect convection to re-develop over central ND this afternoon through this evening and spread eastward. Any thunderstorms will have the potential for MVFR to IFR ceilings and visibilities in heavy downpours. Strong winds and large hail will also be possible with any thunderstorm activity from later this morning through around 06 UTC. Expect a decrease in thunderstorm intensity 06-12 UTC, but isolated to scattered storms may remain. Areas of MVFR ceilings are also possible outside of thunderstorm activity late Tuesday night into early Wednesday morning. Expect a moderate south to southeast surface flow today across the forecast area. Winds are expected to diminish tonight and remain southerly over central ND, but may turn westerly over western ND.

BIS WATCHES/WARNINGS/ADVISORIES

None.