textproduct: Bismarck

KEY MESSAGES

- Isolated strong to severe storms will be possible across portions of western and south central North Dakota through early tonight. Heat bursts associated with dying thunderstorms may also produce locally strong winds.

- Very hot conditions through the weekend, with dangerously high temperatures and heat index values around 100 to 105 degrees.

- The combination of hot, dry, and breezy conditions on Sunday may cause near-critical fire weather conditions in parts of western and central North Dakota.

- The very hot temperatures may continue into Monday southwest, with a slight drop in temperatures elsewhere. The rest of the week remains hot with highs mostly in the 90s, but with some reading above 100 degrees possible in southwest North Dakota.

- Daily low to medium (20 to 40%) chances for thunderstorms remain in the forecast through the work week.

UPDATE

Issued at 1252 AM CDT Sun Jul 26 2026

Radar reflectivity has died off in northeast Montana, but still watching some light returns with a few lightning pulses approach our southwest counties from southeast Montana. As previous shifts have mentioned, main concern with any areas of precipitation would be heat bursts and subsequent stronger wind gusts associated with those. Upstream wind obs in Montana have been pretty tame, but will continue to monitor.

UPDATE Issued at 945 PM CDT Sat Jul 25 2026

Weak radar returns and a few rumbles of thunder can be found over far south central North Dakota this evening, found along the far northern extent of a storm complex found in eastern South Dakota. While these showers and storms are expected to rapidly diminish over the next few hours, more storms upstream in eastern Montana are expected to begin moving across the ND/MT later this evening. With robust inhibition blanketing much of the forecast area, it is uncertain just long these storms will remain active overnight, though a handful of CAMs continue to advertise at least some storms persisting into early hours of Sunday morning. The primary hazard associated with any severe thunderstorm is expected to be damaging wind gusts up to 60 MPH. As mentioned previously, the dry and warm environment aloft is also conducive to heat bursts, meaning that severe wind gusts will be possible even with dying thunderstorms. SPC has placed much of western and portions of south central North Dakota into a level 1 of 5 risk for severe thunderstorms for tonight. Regarding updates, have blended in the latest CAMs into the PoPs through late tonight.

UPDATE Issued at 630 PM CDT Sat Jul 25 2026

Isolated weak radar returns linger over portions of the far southwest at the time of this early evening update. Later this evening into early tonight, showers and storms currently developing upstream in central Montana are expected to begin moving toward the ND/MT border. Short term CAMs continue to have difficulty resolving the longevity of these storms due to the fairly robust capping expected to be in place over western North Dakota by this time, though one or two models continue to propagate at least some showers and storms across western North Dakota into central North Dakota overnight. Considering this, have opted to spread low PoPs (less than 20 percent) overnight through early Sunday morning. In the scenario where storms do end up diminishing rapidly as they cross over the ND/MT border, there is some potential for isolated strong winds as the very hot and dry vertical column across western North Dakota would be supportive of heat bursts. All of that is to say, we will need to monitor conditions as we head into the evening.

DISCUSSION

Issued at 250 PM CDT Sat Jul 25 2026

Very hot temperatures continue across much of western and central North Dakota this Saturday afternoon. Hettinger had already reached 104 degrees as of noon MDT. Many other locations south and west of the Missouri River are also around the 100 degree mark early this afternoon. In Bismarck, our morning fog held temperatures down a bit through mid morning, but we are catching up quick with an early afternoon reading in the mid 90s. The Heat Advisory started at 1 PM CDT and no changes here with temperatures and/or heat indices in the 100-105 range for the Advisory area.

The risk for thunderstorms remains low tonight, especially over northern and eastern portions of the forecast area. The better forcing for ascent will remain over southeast Montana into northwest South Dakota, yet a stronger storm or two can not be ruled out in the far southwest, producing a marginally severe wind gust.

Sunday will be a repeat of today temperatures wise, with forecast highs once again expected to be over 100 degrees over much of the southwest and south central. Only slightly cooler temperatures in the 90s are anticipated along the International Border. The very hot temperatures should keep thunderstorm chances to a minimum. If anything, perhaps an isolated shower/storm brushing the International Border Sunday morning, and possibly some dissipating convection moving into the west later Sunday night. Most of the day will be sunny and hot. The threat for severe storms Sunday is minimal.

The very hot and dry conditions Sunday, combined with a dry cold front passage, may create near critical fire weather concerns Sunday afternoon and early evening. Afternoon relative humidities will drop to 12 to 18 percent across much of western North Dakota. Northwest winds will increase behind the dry cold front to 15 to 20 mph with gust to 30 mph. Due to the recent dry conditions, grasses have begun to cure and near critical fire weather conditions may be reached.

On Monday, the upper level ridge over the Northern Plains flattens a little bringing cooler temperatures northeast, but with very hot temperatures still possible in the southwest and far south central. Will hold off on any extensions of the Heat Advisory, but this is something that may be needed as we get closer to Monday. As was mentioned above, daytime thunderstorm activity will be suppressed due to the hot temperatures. A morning or overnight isolated thunderstorm can not be ruled out though.

The remainder of the work week will continue to bring hot temperatures, mainly in the 90s, but with some 100 degree readings still possible in the southwest. Overall though, not quite as hot as this weekend. Daily low chances (20-30%) thunderstorm chances will remain through the week but with a low predictability in when and where they may occur. There does look to be a little better chance of precipitation in the Wednesday/Thursday timeframe with another impulse that briefly flattens the mean upper level ridge.

AVIATION /06Z TAFS THROUGH 06Z MONDAY/

Issued at 1252 AM CDT Sun Jul 26 2026

VFR conditions generally expected at all terminals through the 06Z TAF period. A few showers and an isolated thundershower are possible across southwest North Dakota overnight, including KDIK, although confidence in impacts and timing was too low to include with this update. Some patchy fog is possible over portions of the James River Valley overnight as well. Light and variable winds overnight will become northwesterly through the day Sunday, with gusts up to 25 knots possible.

BIS WATCHES/WARNINGS/ADVISORIES

Heat Advisory until 9 PM CDT /8 PM MDT/ this evening for NDZ017>020-022-023-025-031>033-035>037-040>044-046>048-050-051- 057>062.