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KEY MESSAGES

- Critical fire weather conditions are expected across much of southwest and south central North Dakota on Monday.

- Smoke from distant wildfires may continue to reduce visibility through Monday.

- Scattered showers and thunderstorms tonight through Monday. A few storms could be strong to severe in central and eastern parts of the state.

- Highs in the 70s on Tuesday, then warming back up to the 80s and 90s through the end of the work week.

UPDATE

Issued at 216 AM CDT Mon Aug 3 2026

Convection is beginning to initiate across southern North Dakota along a broad area of 850-700 mb warm air advection and frontogenesis. Cloud bases remain quite high, but there has been some occasional lightning with this activity, and reflectivity has recently exceed 40 dBZ. So think at least sprinkles are reaching the ground in some areas.

UPDATE Issued at 956 PM CDT Sun Aug 2 2026

The front currently spans from northeast North Dakota down to the south central. Models have pulled back on precipitation tonight with it likely starting tomorrow as an upper level wave moves across the region. Visibility reductions continue to be observed across western North Dakota as smoke settles to the ground. No updates are needed at this time as the forecast remains on track.

UPDATE Issued at 643 PM CDT Sun Aug 2 2026

Smoke continues to filter over the upper level ridge into western and northern North Dakota this evening. Visibility reductions down to 3sm has been observed in Watford City. Visibility reductions are forecast to be more wide spread across the state tonight as the inversion traps smoke down to the surface. A front continues to move across central North Dakota reducing the chances for precipitation tonight as the lift moves further east.

DISCUSSION

Issued at 332 PM CDT Sun Aug 2 2026

Cold front is slowly pushing eastward across North Dakota, and has stalled around central North Dakota. Abundant wildfire smoke has moved in behind this front and has lowered visibilities across the west. These visibilities will remain reduced through at least tonight, and cold linger through much of the day Monday. Ahead of this front remains hot temperatures and modest dewpoints. For the most part these are contained within the Heat Advisory. Some counties just north and east of this Heat Advisory are close to criteria. With the front progressing eastward, these heat index values should be peaking soon. Breezy south winds are also found ahead of this front, with some breezy northwest winds along and behind this front. Low RH values combined with these breezy winds are bringing some critical fire weather conditions across the west. The Red Flag Warning remains as a result, see the Fire Weather Discussion below for more details. For the rest of the night, most CAMs delay convection until later tonight, although the latest NAMNest tries to initiate convection in the more moist central areas this evening. MUCAPE and shear in these areas are somewhat robust this evening, although surface based cape is quite capped. Thus anything that does develop this evening would be elevated, although could be strong to severe with hail to quarters and winds to 60 mph the main threat. The more increased chances for showers and thunderstorms still look to be later tonight through Monday morning as the surface low takes better shape and the upper wave moves threat. Same threats are possible and SPC has maintained a Marginal Risk for central and eastern areas tonight.

Monday, critical fire weather conditions will remain across southwestern ND, and spread slightly eastward into south central portions, mainly west of the Missouri River. This stems from breezy north winds and low humidity values behind today's front despite some cooler temperatures. See the Fire Weather Discussion below for more details. Otherwise the surface low will continue to push eastward, with the cold front reinforced and also pushing eastward. The result could be periods of showers and thunderstorms, especially in the central and east. SPC has maintained a Marginal to Slight Risk for the eastern third of North Dakota. There could be around of strong to severe storms in the morning, then another round in the afternoon and evening. The afternoon and evening storms may have more shear to work with and could be better organized to perhaps supercell storm mode. Higher chances for storms are just east of the CWA, yet any stalling of the front could shift this into the James River Valley and will need to be monitored. Otherwise look for cooler temperatures on Monday with highs near 70 northwest to mid 80s southeast. North northwest winds could get close to advisory level behind this front on Monday, especially with sustained wind speeds. Wildfire smoke may also linger Monday, diminishing somewhat Monday night. Precipitation chances also diminish Monday, with cool lows in the 40s west to 50s east.

Forecast confidence remains high that surface high pressure will build into the region on Tuesday under an upper level longwave trough. This should bring below normal temperatures to all, with highs on Tuesday in the 70s and lows around 45 to 50 Tuesday night. A quick warm up remains favored thereafter, with near normal highs in the 80s on Wednesday increasing to above normal in the 90s along and south and west of the Missouri River by Friday. But there is still uncertainty in the evolution of the synoptic pattern and how much the Hudson Bay low may keep the western CONUS upper ridge from building eastward. This uncertainty is reflected in larger temperature spreads by the end of the work week, and also keeps precipitation chances after Monday very low for the time being. The northwest flow pattern aloft could provide for some breezy conditions through at least mid week. This is of note as dry conditions look to linger through the week, with afternoon RH values forecast in the teens and 20s, with some 30s. This could bring some increased fire weather concerns through the week, depending on if the breezier winds align with the lower humidity values.

AVIATION /06Z TAFS THROUGH 06Z TUESDAY/

Issued at 216 AM CDT Mon Aug 3 2026

Scattered showers and isolated thunderstorms are possible across much of the state late tonight through Monday afternoon. Brief MVFR/IFR visibility restrictions, MVFR ceilings, and gusty winds can be expected with heavier showers and storms. Smoke may also continue to reduce visibility at times, but it is expected to clear from northwest to southeast Monday afternoon and evening. It will become windy on Monday, with northwest to northeast winds around 20-25 kts and gusts to around 30 kts.

FIRE WEATHER

Issued at 315 PM CDT Sun Aug 2 2026

Critical fire weather condition will continue today through Monday for portions of western and south central North Dakota. Rest of today, cold front will continue to progress eastward and shift a breezy southerly wind to a breezy westerly wind. Meanwhile, very low humidity vales in the teens across the west will bring critical fire weather conditions. Thus the Red Flag Warning remains for much of western North Dakota through this evening. Outside of this warning could still be some near critical fire weather conditions, especially with shifting winds from the mentioned front. Critical fire weather conditions looks to be found across much of these same areas on Monday into Monday evening. With low humidity recoveries tonight also in these areas, have decided to extend the Red Flag warning through tonight and into Monday for all of the current counties except Williams and McKenzie county. Showers and thunderstorms may also be found tonight, mainly in northwest, central, and eastern portions. The chance of a wetting rain is low. Behind this front will also be wildfire smoke, which could reduce visibility at the surface.

Monday, critical fire weather conditions will remain for southwestern portions of the state and move into some south central portions of the state. These areas will see breezy northerly winds and afternoon humidity values in the 20s. Even with some cooler temperatures, winds, lapse rates, and still low humidity values still support critical fire weather conditions. Thus a Red Flag Warning has been extended for southwestern portions (as mentioned), and issued for some south central portions, mainly zones just west of the Missouri River. These breezy conditions will be found elsewhere, although afternoon humidity values should be above 35 percent. More shower and thunderstorm chances will continue for central and eastern portions on Monday, with low chances for a wetting rain. An isolated severe storm is also possible tonight through Monday in these same areas.

BIS WATCHES/WARNINGS/ADVISORIES

Red Flag Warning until 9 PM CDT /8 PM MDT/ this evening for NDZ018-031>033-040-041-043-044. Red Flag Warning from noon CDT /11 AM MDT/ today to 9 PM CDT /8 PM MDT/ this evening for NDZ019-020-034-042-045.