textproduct: Bismarck

KEY MESSAGES

- Below normal temperatures continue through tonight, with highs in the mid 40s to mid 50s and lows in the 20s.

- Warmer beginning Thursday, but sub-freezing low temperatures return to the forecast Saturday night.

- Only occasional low chances for light precipitation through the middle of next week.

UPDATE

Issued at 639 AM CDT Wed May 6 2026

A deck of stratus clouds has been persisting longer than expected over central and eastern North Dakota since last night. The sky cover forecast has been updated to better reflect current observations and trends. It does appear that the RAP is starting to better capture these clouds, which projects them gradually eroding from west to east this afternoon. Meanwhile, a clear sky across western North Dakota overnight allowed temperatures to plummet into the teens in low-lying, sheltered areas.

DISCUSSION

Issued at 305 AM CDT Wed May 6 2026

A persistent Hudson Bay low will maintain a predominant northwest cyclonic flow pattern over the Northern Plains through the weekend. Occasional embedded shortwaves combined with diurnal heating could generate a few light showers at times, but the probability for measurable precipitation at any given location (aside from the southwest corner of the state) is very low.

An unseasonably cold and dry air mass remains entrenched over the region this morning within a broad surface ridging regime. A shortwave digging south through Saskatchewan will reach North Dakota this afternoon and commence weak warm air advection, but not enough to allow afternoon temperatures to rise above the upper 40s east to mid 50s west. The timing of the shortwave is highly favorable for diurnal shower development, but as was the case yesterday, there is uncertainty if there will be enough moisture available. We kept a 15 to 20 percent chance of light showers in the forecast from the Turtle Mountains through the James River Valley this afternoon. Most of any precipitation that develops would fall as rain, but it may be cold enough for snow, sleet, or graupel in the Turtle Mountains and Devils Lake Basin areas if anything develops early in the afternoon. Winds this afternoon will remain out the northwest, but not be as strong as the past few days at only around 10 to 15 mph.

Another night of sub-freezing temperatures is forecast to be followed by a more substantial warmup on Thursday, with highs returning closer to early May normals in the upper 50s to mid 60s. Another shortwave embedded in the northwest cyclonic flow could bring some light rain showers and perhaps a stray thunderstorm across southwest North Dakota Thursday afternoon. The warming trend continues on Friday as the northwest flow aloft briefly turns anticyclonic. The NBM shows high confidence in above normal high temperatures in the upper 60s to mid 70s across the western half of the state on Friday. Stronger northwest winds are also set to return on Friday though, which could lead to near-critical fire weather conditions. A slightly more potent shortwave is then forecast to dig through the Canadian prairie provinces towards the western Great Lakes late Friday through Saturday, driving a cold front through the region. This is forecast to lead to a modest cool down for Saturday, perhaps with a relatively higher but still overall low chance for showers. Meanwhile, a separate shortwave ejecting off the Northern Rockies could bring more persistent shower activity to far southwest parts of the state on Saturday.

The cooler air mass is forecast to linger through the weekend, with low temperatures mostly in the 30s. Saturday night is favored to be slightly cooler than Sunday night, with the latest NBM projecting widespread lower to mid 30s and even some upper 20s. With the growing season officially beginning on Friday, it is looking increasingly likely that frost/freeze headlines will be needed this weekend. Ensembles favor slightly warmer temperatures next week (60s and 70s for highs, 40s for lows) as flow aloft remains northwesterly but turns more active as upper level ridging builds over the Desert Southwest. Precipitation chances are likely to become more frequent and perhaps higher early to mid next week, but predictability at this time range remains low.

AVIATION /12Z TAFS THROUGH 12Z THURSDAY/

Issued at 639 AM CDT Wed May 6 2026

VFR conditions are expected through the forecast period. A stratus deck with ceilings around 5,000 ft will persist over central and eastern North Dakota this morning, slowly lifting and eroding from the west through the afternoon. Isolated light rain showers could approach KJMS this afternoon, with no impacts to aviation expected. Light and variable winds early this morning will become northwesterly around 10 kts later this morning and afternoon, then return to light and variable this evening.

BIS WATCHES/WARNINGS/ADVISORIES

None.