textproduct: Bismarck

KEY MESSAGES

- Chances for showers and thunderstorms increase into this weekend, with strong to severe storms possible both Saturday and Sunday.

- Temperatures remain at or slightly below normal today, then will trend warmer this weekend.

- Temperatures trend much warmer next week, with low to medium chances for daily showers and thunderstorms.

DISCUSSION

Issued at 425 AM CDT Fri Jun 26 2026

Currently, zonal flow aloft with a S/WV impulse propagating eastward across the Dakotas early this morning. This wave results in an area of showers developing slowly east and slightly north across southwest and south central areas of the state. This activity will continue east-northeast this morning, with further development across my east into this afternoon. Mostly dry over the western half of the state today as a S/WV mid level ridge attempts to build north into the High Plains/western Dakotas this afternoon. Temperatures today will be similar to slightly warmer compared to Thursday as a result, along with a steady southeast breeze with gusts up to near 25 mph at times as we mix.

Deep upper level low currently along the western Canadian coast will continue to slide southeast into the Pacific Northwest coastal area tonight. This will result in a long wave trough over the western CONUS amplifying, transitioning our flow aloft to southwesterly tonight. Still expect High Plains convection along a lee side sfc trough later today and this evening, lifting north-northeast into the Northern Plains tonight. A nocturnal low level jet (LLJ) is also still depicted developing across the central and eastern Dakotas late tonight, helping to maintain/initiate new convection over central/portions of eastern ND late tonight into Sat morning with models projecting near 1000 J/kg of MUCAPE though weak shear.

Not much has changed for this weekend's outlook, with southwest flow aloft increasing as the large upper level low develops east over much of the western CONUS within a long wave trough regime. Models continue to show robust instability and favorable shear over the state on Saturday, as warm air and moisture advection increase along and ahead of a deepening sfc trough across the far western Dakotas. Severe weather scenarios look to be either convection to our west moving east into the area, and/or possible discrete convection along the sfc trough/frontal boundary firing up as a strong embedded S/WV lifts into the area. The former scenario would see wind and hail as main threats, with the latter seeing all facets of severe weather possible. SPC has kept pretty much all of western and central North Dakota in the Slight Risk (level 2 of 5) area for Day 2 (Saturday).

For Sunday, south to north orientated sfc trough/frontal boundary becomes quasi-stationary/redevelops over the central Dakotas, leading to another round of strong to severe convection during the day along to east of this boundary. SPC has eastern areas of the state in the Slight Risk area for Day 3 for this. Across western and central North Dakota, we're in the Marginal Risk (level 1 of 5) for severe weather as another S/WV and associated sfc low move north-northeast across the High Plains/western Dakotas area Sunday night. Would not be surprised if this conditional outlook is upgraded in future SPC outlooks.

In addition to the active weather pattern discussed above, forecast temperatures this coming weekend will finally warm to above normal for late June, with forecast highs in the upper 70s to near 90, depending on what side of the sfc front you are. Southeast winds also increase, especially on Saturday as the sfc trough deepens to the west, with peak gusts approaching advisory criteria (45 mph) central and east.

We trend cooler and drier for Monday as the closed low lifts northeast through the Northern Plains. Thereafter, we remain in a southwest flow aloft pattern, with a quasi-stationary sfc trough in the lee of the Rockies. Consistent southerly low/mid level flow results in continued WAA and a steady increase in low level moisture through next week. NBM and ensembles thus continue to show a nice warming trend next week, with forecast highs by the end of next week for the July 4th Holiday warming into the mid 80s to mid 90s. The pattern aloft will also yield near daily thunderstorm chances, but more conditional and dependent on convective inhibition, any nocturnal LLJ, or any embedded impulses moving through.

AVIATION /06Z TAFS THROUGH 06Z SATURDAY/

Issued at 122 AM CDT Fri Jun 26 2026

A weather disturbance will bring an area of showers and possibly a few rumbles of thunder into southwestern and south central North Dakota tonight, expanding north and east Friday morning while ending in the west. MVFR ceilings and visibility are possible with any showers. In addition, MVFR-IFR ceilings are forecast to develop with these showers and may last through Friday morning and into the afternoon over parts of western and central ND.

BIS WATCHES/WARNINGS/ADVISORIES

None.