textproduct: Bismarck

KEY MESSAGES

- Critical fire weather conditions and strong winds in parts of Central North Dakota and the James River Valley into early this evening.

- Windy conditions and low humidity values through the rest of the upcoming week may lead to daily critical fire weather conditions.

- A low chance (15-25%) for thunderstorms and showers across the east Thursday. Another chance (40-60%) of rain this weekend.

UPDATE

Issued at 541 PM CDT Tue May 12 2026

Quick update to cancel the western row of counties from the Wind Advisory, as wind speeds and gusts have decreased to magnitudes comfortably below advisory criteria in that area as the surface pressure gradient and winds aloft relax. We anticipate allowing the rest of the Wind Advisory to expire as scheduled at 7 pm CDT.

DISCUSSION

Issued at 342 PM CDT Tue May 12 2026

There is an upper level low located over the Great Lakes with an upper level ridge over the west. This has placed the Northern Plains in the in northwesterly flow. The surface pressure gradient is in a northwest to southeast orientation thus resulting in windy northwest winds. There are 40 kt winds at 850 mb aloft which have mixed down to the surface resulting in windy conditions across the eastern half of the state. This has led to windy conditions and dry conditions this afternoon (see the fire weather discussion for more information.) Temperatures this afternoon have warmed into the 70s. Surface high pressure is forecast to move into the region tonight bringing in calm winds. Surface high pressure could bring cooler overnight lows across the region. There is a low chance of frost as lows could drop down into the mid 30s, but this is less likely.

Tomorrow, another upper level low is forecast to dig across the Pacific Northwest. This will lead to surface low pressure over eastern Montana and surface high pressure out over Minnesota. Thus, leading to a tight north south orientated pressure gradient producing windy southeasterly winds. Winds are forecast to be around 20 to 30 mph by the afternoon into the overnight hours. High temperatures tomorrow are forecast to warm in to the upper 70s to upper 80s out west. Dry and windy conditions will lead to more critical fire weather out west.

The aforementioned upper low over the Pacific northwest will deepen east of the Northern Rockies moving out over the Northern Plains Thursday into Friday. There is a low chance for thunderstorms across the eastern half of the state, but the majority of western and central North Dakota looks to be in the dry slot of the upper low. This upper level low is forecast to bring high winds across much of the northern half of the state Thursday and across much of the state Friday. A 60 to 65 kt 700 mb jet streak is forecast to line up across northern North Dakota Thursday afternoon into early Friday supporting high winds. Dry conditions will continue, and with high winds will lead to critical fire weather concerns until the weekend. Temperatures will remain in the 70s and 80s until the weekend.

Surface high pressure is forecast to move across the region Friday night, thus leading to clearing skies and a colder airmass. This could bring back chances for frost across the north for Saturday morning. A subtle ridge is forecast to move off to our east resulting in southwesterly flow Saturday into Sunday. A trough will move through the region bringing in a chance for some rain this weekend, which will bring a subtle reprieve from the dry and windy conditions. The pattern remains to look active in the extended.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 1215 PM CDT Tue May 12 2026

VFR conditions will continue across the region for the next 24 hours. A layer of scattered to few cumulus is forming across much of the central and western half of the state. Winds will continue out of the northwest with KMOT and KJMS having the windiest conditions this afternoon. Surface high pressure will move into the region tonight resulting in lighter winds and a wind shift out of the south by tomorrow morning. Winds will pick across the western half of the state by tomorrow afternoon.

FIRE WEATHER

Issued at 356 PM CDT Tue May 12 2026

Critical fire weather conditions will continue through the week. This afternoon the main threat is east of the Missouri as windy conditions continue across the eastern half of the state. Minimum relative humidity is forecast to drop as low as 20 percent across the east with the windy conditions. A strong northwest wind will subside tonight as surface high pressure moves through the region with fair overnight recoveries. This will also bring a wind shift by tomorrow morning.

Southeast winds tomorrow are forecast to be around 20 to 30 mph by the afternoon out west moving across the central and James River Valley Wednesday night. Minimum relative humidity is forecast to drop down to around 15 percent out west. Thus, the west and portions of the south central will see another round of critical fire weather conditions. Overnight recoveries are forecast to be poor Wednesday night helping further critical fire weather conditions.

Critical fire weather conditions will return again Thursday and Friday across the whole region. Another dry system will move through the region Thursday and Friday bringing in high winds across the state. There is also a low chance for thunderstorms Thursday afternoon. Strong westerly winds could approach 40 mph sustained with gusts up 60 mph possible. The minimum relative humidity is forecast to drop down around 15 to 25 percent. Any fires that ignite will spread rapidly and become difficult to control or suppress.

Rain chances return to the region Saturday night into Sunday bringing in some temporary relief.

BIS WATCHES/WARNINGS/ADVISORIES

Red Flag Warning from 11 AM CDT /10 AM MDT/ to 10 PM CDT /9 PM MDT/ Wednesday for NDZ001-002-009-010-017-018-031>033-040>045. Red Flag Warning until 9 PM CDT this evening for NDZ003>005- 011>013-021>023-025-035>037-046>048-050-051. Wind Advisory until 7 PM CDT this evening for NDZ005-013-023- 025-036-037-047-048-050-051.