textproduct: Bismarck

KEY MESSAGES

- Dry conditions continuing through Thursday night.

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

- Low to medium shower/thunderstorm chances return Friday morning and will continue through the weekend and into early next week.

- An isolated severe thunderstorm is possible on Friday, mainly across south-central and southeast North Dakota.

UPDATE

Issued at 955 PM CDT Wed Aug 26 2026

Added patchy smoke across the forecast area as wildfire smoke has settled near the surface once again.

UPDATE Issued at 635 PM CDT Wed Aug 26 2026

Little to no updates needed early this evening. There is a strip of smoke, mostly aloft, across central and southeastern North Dakota. At times visibility may drop to 6 miles.

DISCUSSION

Issued at 230 PM CDT Wed Aug 26 2026

Water vapor satellite imagery and upper air analysis show a sharp upper trough continuing eastward across the Great Lakes region, and a mid/upper ridge axis across the central and northern Rockies. At the surface, a weak ridge is settling in across western North Dakota, and light northwest winds are gradually becoming even lighter and more variable this afternoon. Overnight tonight into Thursday morning, light winds and clear skies in association with this surface ridge will support optimal radiational cooling which may lead to patchy shallow fog in some of the river valleys and other lower elevation areas. However, given the presence of this drier air mass, coverage will be limited. Lows tonight should generally bottom out in the upper 40s to low 50s. Increasing southerly/southeasterly winds and ample diurnal heating should quickly mix out any fog that develops Thursday morning. The primary mid/upper ridge axis will nose out over eastern Montana and western North Dakota by Thursday afternoon, and this will support slightly warmer temperatures with afternoon highs raging from upper 70s to upper 80s. It's possible a few locations across southwest North Dakota surpass the 90-degree mark. Additionally, the aforementioned increasing southerly winds ahead of a strengthening surface trough across central Montana along with 20-25% RH across western North Dakota could present some modest fire weather concerns, but recent rainfall should quell this concern some. Increasing cloud cover, along with breezy conditions keeping the boundary layer somewhat mixed, should keep Thursday night lows slightly above average in the upper 50s to low 60s.

Several CAMs and global models are supporting the idea of a band of elevated showers and storms sweeping from west to east across the state from early Friday morning through early Friday afternoon. This idea is generally supported as widespread lift, caused by an axis of mid-level WAA traversing across the state in addition to an incoming shortwave trough rounding the northern periphery of the mid/upper ridge axis (which should be centered just east of the Rockies by Friday morning), overspreads much of the forecast area. MUCAPE around 1000-1500 J/kg and effective shear around 40 knots could support some organized convection capable of small hail. One caveat to Friday morning/early Friday afternoon storm chances will be some modest CIN across the region. However, the aforementioned synoptic lift should be more than enough to overcome this. Later in the day, uncertainty about the evolution of the leftover elevated convection and the potential for additional afternoon/evening surface-based convection remains relatively high. Questions that remain are: how quickly will elevated showers and storms exit eastward, how much does the atmosphere destabilize in the wake of this activity, and how far east is the next shortwave trough by Friday evening? Currently, guidance suggests destabilization of the atmosphere Friday afternoon will be confined to mainly southern North Dakota with the warm front likely staying south of I-94. However, the shortwave trough axis looks to still be out over western/central Montana by Friday evening keeping much of the broad ascent just west of the forecast area. Still, a surface-based storm or two cannot be ruled out along or south of the warm front Friday afternoon and evening. These potential storms could be strong to severe before the loss of diurnal heating late Friday evening/Friday night. Generally speaking, highs Friday afternoon will be slightly above average with low to mid 90s across southwest ND and upper 70s to low 80s across northern and eastern ND.

Mid range guidance suggests the primary mid/upper ridge axis will stall out across the central plains keeping zonal flow aloft across the north-central CONUS. Embedded shortwave impulses traversing in this flow aloft will support periodic chances for showers and storms across the forecast area through much of this weekend. Global guidance continues to suggest that sufficient instability and shear will be in place Saturday (and perhaps Sunday?) to support strong or marginally severe storms. Broad and deep troughing across the western CONUS will place southwesterly flow aloft across the northern plains early next week. A parade of shortwave troughs embedded in this flow will continue supporting periodic shower and storm chances through the middle of next week. Also, temperatures are forecast to remain near average this weekend into early next week.

AVIATION /00Z TAFS THROUGH 00Z FRIDAY/

Issued at 955 PM CDT Wed Aug 26 2026

All VFR through the period. Tonight will be mostly light and variable winds before sustaining from 140 Thursday 10-15kts. Patchy wildfire smoke may reduce visibilities.

BIS WATCHES/WARNINGS/ADVISORIES

None.