textproduct: Bismarck

KEY MESSAGES

- Isolated to scattered severe thunderstorms are possible this afternoon and evening. Expected hazards include hail up to golf ball size and damaging winds up to 70 mph, with a tornado or two possible.

- Smoke from distant wildfires will make skies hazy and may bring reduced surface visibility today.

- Very hot conditions will return through the weekend, with dangerous heat index values around 100 to 105 degrees expected this weekend.

- The combination of hot, dry, and breezy conditions will create near-critical fire weather conditions today and again on Sunday, mainly in southwestern and some south central portions.

UPDATE

Issued at 949 AM CDT Fri Jul 24 2026

Low level stratus that had developed earlier this morning over much of the south central, including the James River Valley, is rapidly eroding. Therefore, morning stratus shouldn't have any impact on high temperatures today, as well as severe weather potential. Another thing is smoke. Yesterday's highs wound up about five degrees short across much of the area due to thick elevated smoke. Despite both the HRRR and RAP Smoke models suggesting similar concentrations, smoke doesn't appear as thick this morning on Geocolor satellite, on various webcams, and visually at the office. Therefore, unsure if there will be enough smoke to inhibit temperatures in a meaningful way today. If not, scattered severe thunderstorms are likely this afternoon. If so, things are a bit more questionable across the CWA.

UPDATE Issued at 642 AM CDT Fri Jul 24 2026

Low clouds, mist, and patchy fog continue to be found across the southcentral and southeast. This low level moisture has become quite robust, although fog reports have been limited. Maintained patchy fog and low clouds through at least mid morning. Otherwise, morning thunderstorms have mostly remained in souther Canada. A few thunderstorms are currently in Montana along the surface trough and warm front. Perhaps these move into northwestern ND this morning as the mentioned trough moves eastward and MUCAPE remains modest. Wind would be the main threat with any thunderstorm that develops this morning.

DISCUSSION

Issued at 405 AM CDT Fri Jul 24 2026

Increased low level moisture will bring low clouds and perhaps some patchy fog across south central and southeastern portions this morning. Surface trough with broad ridging aloft will bring a few different weather impacts today. To start, SPC has maintained the Slight Risk for much of central and eastern ND, while expanded the Marginal Risk into most of the state except the southwest. Overall the setup remains similar to previous discussions. Surface trough will move through today, with a weak cold front replacing a weak warm front this afternoon and evening. Modest instability and shear will be found along these fronts bringing all hazards of severe weather possible, if a stout cap can be broken. The likely main threat will be wind. Inverted V soundings, high DCAPE values, and modest to high 0 to 3 KM shear all indicate winds of 70 mph possible, with perhaps higher winds depending on what storm mode develops. Current thinking is storms are multi cluster today, with a brief window for supercells. Any supercells could bring large hail to golf ball in size. SPC has introduced an intensity level 1 for hail in the slight risk area, indicating hail 2 inches or greater is possible. This would be very conditional on rotating supercells and timing of the higher shear influencing these. This higher shear may be delayed to behind the surface trough, thus kept with golf ball sized hail for today. A tornado or two also remains possible although are still conditional on a surface based supercell storm mode and some interactions with either storms or remnant boundaries from this mornings convection if any. STP values around 1 are also found for a limited time this afternoon. Thus will maintain mention of a tornado or two possible, although chances still remain low. Timing wise, some thunderstorms are currently along the cold front in southern Canada. These thunderstorms could clip northern ND this morning, although should remain elevated. As this front and surface trough moves through this afternoon and evening, look for better chances of severe weather in central and eastern ND especially in the more moisture rich areas from this morning. This is again assuming the cap can be broken today. The initial thunderstorms should push eastward by early to mid evening. Some CAMs have isolated severe thunderstorms redeveloping along the stalled boundary later this evening into the early overnight hours. Although instability along this boundary lowers, shear will remain high. Chances for this redevelopment appear low at this time, although any sort of low level jet could be enough to overcome the lower lift along the stalled boundary thus have placed in some slight PoPs for this.

The next areas of concern for today are hot temperatures and the potential for near critical fire weather conditions. Warm front moving through will bring warming temperatures forecast in the 90s to lower 100s for much of the state today. However, HRRR smoke showing abundant wildfire smoke both aloft and at the surface moving in by this afternoon and lingering through tonight. Local research suggests abundant vertically integrated smoke could impact temperatures 5 to 10 degrees. Forecast HRRR Vertically Integrated Smoke values today appear to be modest yet may impact high temperatures, thus have lowered them a few degrees from the NBM. This lowering also lowers apparent temperatures today enough to create uncertainty on heat products for today. Thus will hold off, although some south central areas will get close to heat index values near 100 degrees. These hot and dry conditions, combined with increased westerly winds from the mentioned front could bring some near critical fire weather conditions to southwestern and south central portions this afternoon and evening. The number of hours of these near critical conditions combined with reported partially green fuels has cause to hold off on any fire weather products as well for today.

This weekend, hot temperatures and dangerous heat remains the biggest concern. Stalled front lifts back north Saturday, while the upper level ridge also looks to rebound slightly. This could be the hottest day of the weekend, although may depend on how much wildfire smoke lingers across the area. Widespread temperatures forecast in the 100s could lead to dangerous heat index values also in the 100s. Still appears to be a dryer heat compared to last weekend, although could still at least hit advisory levels. Although confidence is increasing in a heat product for this weekend, would still like to see how smoke impacts temperatures today, which could play out similar this weekend. Even so, those with outdoor plans will want to use caution given the elevated potential for dangerous heat this weekend. Weak instability, surface low, and the mentioned boundary could bring afternoon and evening thunderstorms each day this weekend. An isolated severe storm is possible as well each day, although severe chances look to be higher to our south on Saturday, and to our east on Sunday. Light winds on Saturday should limit the fire weather threat, although RH values will be in the teens and 20s. Low RH values and perhaps some increased westerly winds are forecast for Sunday, bringing near critical fire weather conditions possible for southwestern portions Sunday afternoon and evening.

Early to mid next week, upper level ridge looks to linger across the central US bringing a similar pattern of hot and generally dry conditions. Any weak disturbances or flattening of this ridge could bring some isolated to scattered thunderstorms, although current forecast has generally low PoPs. The dry nature of this ridge could limit the heat risk despite forecast highs in the 90s to low 100s. Low temperatures at night will also be mild and generally in the 60s. Fire weather conditions will also greatly depend on any days with increased winds, with the current forecast showing generally light winds to start next week. Overall look for well above normal temperatures to continue next week with low chances for precipitation.

AVIATION /12Z TAFS THROUGH 12Z SATURDAY/

Issued at 642 AM CDT Fri Jul 24 2026

Some lower clouds and patchy fog will linger this morning across portions of south central and southeastern ND, with VFR conditions expected elsewhere. For now expect these lower clouds to be confined from the KBIS to the KJMS area and southward, with MVFR to IFR ceilings possible through this morning. Generally VFR conditions are then expected for for the rest of today. Wildfire smoke could bring FEW to SCT cloud appearance aloft, while reduced visibilities at the surface are also expected today through tonight. Showers and thunderstorms may also return today through tonight. For now confidence was only high enough to include PROB30 groups at KBIS and KJMS. A breezy westerly wind is also expected today, becoming light and variable tonight.

BIS WATCHES/WARNINGS/ADVISORIES

None.