textproduct: Bismarck

KEY MESSAGES

- Mainly dry conditions through Thursday evening.

- Near to slightly above average temperatures continue through the week into early next week.

- Low to medium shower/thunderstorm chances return Friday, and continue through the weekend into early in the work week.

- An isolated severe thunderstorm is possible on Friday, especially in south central and southeastern portions.

UPDATE

Issued at 953 AM CDT Wed Aug 26 2026

Forecast remains on track with little to no updates needed. Patchy fog across north-central portions of the state has largely mixed out, and mostly clear skies will dominate the region today.

DISCUSSION

Issued at 402 AM CDT Wed Aug 26 2026

Surface high pressure will bring dry conditions and mainly clear skies today, although some clouds may linger across the east as northwest flow aloft continues. North northwest winds will be much reduced today as well, with more steady winds lingering across the east. Low afternoon RH in the 20s will be found in the west today, although light winds should limit any fire weather concerns today. Look for near normal highs today in the mid 70s to mid 80s. Tonight, mainly dry conditions look to continue. There are some CAMs that bring isolated showers to the southwest along a weak boundary. An overall dry atmosphere and lack of instability should limit this threat, thus the outgoing forecast remains dry. Winds will become light and variable for the most part tonight. Clear skies could combine with these light winds to produce some patchy fog, although dry air in place will limit this potential so have not included it in the current forecast. Lows tonight will be in the mid 40s to mid 50s. The surface high moves across the eastern half of the state on Thursday, with an upper level ridge settling in across the west. The result will be another mainly dry day with continued near to slightly above normal high temperatures in the upper 70s to upper 80s. Developing surface low to the west will switch the winds to the south, and be sustained at 10 to 20 mph across the west. Meanwhile low afternoon RH values in the 20s could also be found in the west on Thursday. This could bring some increased fire weather concerns to these areas, although winds are expected to remain short of critical fire weather criteria. Surface low moves more into western MT Thursday night, bringing a steady southerly wind to much of the area. Meanwhile the ridge aloft breaks down, lifting an elevated warm front across the state. This could bring some isolated to scattered showers and thunderstorms across the west Thursday night. Right now instability and shear look low to modest Thursday night, although the location of the low level jet may help overcome this. For now the severe weather threat is low yet worth monitoring.

The initial upper level wave and surface low then looks to move through Friday. The warm front associated with this feature could bring high temperatures into the 80s to lower 90s for much of the area. The potential for severe weather will also return with this feature, although timing of the wave will determine where thunderstorms set up. If thunderstorms can develop early enough across the CWA, large hail and damaging winds will be the main threat. SPC has clipped parts of south central and southeastern portions of the CWA with a Marginal Risk for severe weather on Friday to account for this potential. This area looks to have an additional push of moisture which could help with convection. Lingering low level jet aloft could also provide some increased shear in this area further increasing the chances for severe weather, and may also bring a breezy south wind to the CWA. The shear vector may also favor discrete supercells, at least initially, along this boundary. An isolated tornado would also be possible along the warm front in this area, although is very conditional and may be more favored in South Dakota where the better shear is. Overall this set up could be the next chance for at least isolated severe thunderstorms and will be worth monitoring for the latest updates. Zonal flow aloft with embedded shortwaves, combined with a lingering surface low, could continue near daily chances for showers and thunderstorms through the weekend. CSU- MLP also showing the isolated severe weather threat could continue through the weekend. Warm front stalls on Saturday, lingering slightly above normal temperatures in the 80s. A weak cold front could move through Sunday, slightly cooling temperatures yet still bringing near normal highs. Mild lows in the 50s to lower 60s will continue through the weekend. Fire weather concerns Friday through the weekend overall look low. Some low RH values will be found in the west on Friday, although the breezier southerly winds will be located more in central and eastern portions. The rest of the weekend sees improved humidity values with generally light winds. Southwesterly pattern aloft then looks to continue into early next week, bringing more near to slightly above normal temperatures along with near daily chances for showers and thunderstorms.

AVIATION /12Z TAFS THROUGH 12Z THURSDAY/

Issued at 642 AM CDT Wed Aug 26 2026

Mainly VFR conditions expected through the forecast period. Some patchy fog may be found in the north through mid morning, although confidence was not high enough to include in the TAFs at this time. FEW to SCT MVFR to low VFR clouds may also be found in the east this morning. These could impact the KJMS area, although coverage was too isolated to include in the TAFs. Otherwise look for mainly clear skies throughout the forecast period, with only a FEW afternoon VFR clouds. Winds will overall be a light north northwest wind today, becoming light and variable then east to southeast tonight.

BIS WATCHES/WARNINGS/ADVISORIES

None.