textproduct: Bismarck

KEY MESSAGES

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

- The combination of hot, dry, and breezy conditions today 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 readings above 100 degrees possible in southwest North Dakota.

- Widespread precipitation chances are low until midweek, when there is a 30 to 50 percent chance for showers and thunderstorms across the forecast area.

UPDATE

Issued at 919 AM CDT Sun Jul 26 2026

A couple areas of fog earlier this morning are quickly eroding. Otherwise no changes to the going forecast. Another very hot day today, especially far southwest and south central. There is some guidance that suggests the far south central could overperform with high temperatures today. Will monitor but now will keep forecast highs here as is, 100 to 105 degrees from around Hettinger to Bismarck and Linton. Updated text products out shortly.

UPDATE Issued at 646 AM CDT Sun Jul 26 2026

Patchy fog has led to multiple automated sites reporting reduced visibility this morning, so did expand mention of fog in gridded forecast, although reductions have been pretty transient both spatially and temporally. Radar returns have pretty much entirely sunk south of the ND/SD state line, with an additional area of convection in southwest Manitoba that is currently tracking to cross the International Border east of the forecast area. High-res guidance has backed off some on showers and thunderstorms moving through the Turtle Mountains area today but have left in low chance mention for now.

DISCUSSION

Issued at 347 AM CDT Sun Jul 26 2026

This morning, an area of showers and thunderstorms was ongoing in far southwest North Dakota along the state border. The main concern with this area of convection would be isolated strong winds, as the very warm and dry air mass is supportive of heat bursts. Elsewhere, fog has been developing across parts of the James River Valley and up through much of north central North Dakota, and will continue to monitor in case any additional products are needed for this. High-res guidance has not done well already catching on to the reduced visibilities, but would expect at least patchy fog to persist into mid morning.

Another hot and mostly dry day is in the forecast today, as the upper ridge axis continues to extend over the north central CONUS with a low-level thermal ridge aiding in bringing well above average temperatures to the state. Forecast highs range from the lower 90s along the International Border to the 100 to 105 range across the southwest and south central. A Heat Advisory remains in effect for most of the forecast area, with the exception of the northern two tiers of counties.

Other forecast concerns today include a low chance for a few showers and thunderstorms today in the Turtle Mountains area as a weak surface low tracks along the International Border, and patchy near-surface smoke across the southwest and south central. HRRR smoke model hasn't been performing the best the last day or two but is very confident in a plume of thick smoke accompanying the aforementioned surface low and associated frontal boundary, so wanted to add it into the gridded forecast. We also continue to mention near-critical fire weather conditions across most of western and parts of central North Dakota, with a northwest breeze today and minimum relative humidity in the lower to mid teens for areas south and west of the Missouri River.

Temperatures "cool down" a few degrees for the first half of the work week, but forecast highs are still in the 90s to around 100 degrees F. Chances for widespread precipitation are low Monday and Tuesday, although can't rule out a few isolated showers and thunderstorms associated with embedded impulses passing over the ridge axis. More substantial blended PoPs emerge on Wednesday as ensemble guidance is more confident on a stronger wave moving across the Dakotas. Temperatures to end the week cool down a bit further into the upper 80s to upper 90s, although latest NBM percentiles show potential for warming up slightly for next weekend. NSSL machine learning is currently favoring Wednesday and Thursday for the highest likelihood of severe thunderstorms, but any day for the next week will have some potential for any storms that can develop to be at least strong. There finally starts to be a signal for closer to normal temperatures as we get past the first few days of August.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 646 AM CDT Sun Jul 26 2026

VFR conditions expected overall at all terminals through the 12Z TAF period. Patchy fog has been observed across parts of the north central and James River Valley, so do have TEMPO groups in at KMOT and KJMS for reduced visibility. Light and variable winds this morning will become northwesterly through the day, with isolated gusts up to 25 knots possible. Wildfire smoke could lead to both hazy skies and potentially minor surface visibility reductions, although too low of confidence to include at any terminal with this update. Most likely terminal that could be impacted by this is KDIK.

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.