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KEY MESSAGES

- Near critical to critical fire weather conditions for much of North Dakota today.

- Warmer and windy today with scattered showers and isolated thunderstorms in the afternoon and evening. Then seasonably cool temperatures return for the weekend.

- Near to sub-freezing low temperatures are possible across northern North Dakota tonight and most of the state Saturday night.

- Warm and windy weather next week could lead to daily critical fire weather conditions, especially in western North Dakota.

UPDATE

Issued at 1245 PM CDT Fri May 8 2026

Main update was to expand the Red Flag Warning to include much of central North Dakota. These areas are seeing higher than forecast winds in excess of 20 mph combined with low RH values in the teens and 20s. Given the warming temperatures and windy conditions today, decided to expand. All Red Flag Warnings are now in effect until 10 PM CDT tonight. Otherwise the forecast remains on track. There is some frost potential in the north tonight into Saturday morning. This will be evaluated further for a later update.

UPDATE Issued at 953 AM CDT Fri May 8 2026

Stay showers over south central North Dakota have exited the area with quiet weather continuing. Otherwise, main change was to expand the Red Flag Warning over far western North Dakota southward along the Montana border through Bowman County.

UPDATE Issued at 649 AM CDT Fri May 8 2026

Radar shows a few stray showers moving southeast through south central North Dakota early this morning, but nothing more than sprinkles are likely reaching the ground due to a very dry layer of air sampled by the 12Z BIS RAOB. The forecast for today remains on track. Current conditions and trends were blended in for this update.

DISCUSSION

Issued at 522 AM CDT Fri May 8 2026

Persistent northwest cyclonic flow pattern progged to remain over the Northern Plains today into Sunday. Today will be warmer but windier ahead of a cold front being driven down from Canada by a shortwave digging into the Red River Valley this evening. High temperatures in the mid 60s to to mid 70s yielding afternoon RH around 20 percent combined with northwest winds around 25 to 30 mph and gusting to near 40 mph are expected to result in critical fire weather conditions in far northwest and parts of south central North Dakota, including the James River Valley. Red Flag Warnings have been issued, with more detailed information in the Fire Weather section below. Most CAMs are simulating isolated to scattered high- based showers developing ahead of the front in the mid to late afternoon, becoming scattered to widespread with the frontal passage and stronger DCVA this evening. There may be enough CAPE to support a few thunderstorms this afternoon and evening as well, but the ensemble range of outcomes is from zero CAPE to as much as 500 J/kg, with these differences apparently being driven by surface dewpoint uncertainty. An example of the worst-case scenario, which may be borderline unreasonable, is the 06Z NAMnest that brings a mature bowing segment as part of an MCS through the Turtle Mountains and Devils Lake Basin areas this evening. Up to 500 J/kg of CAPE would support marginally severe convection in the high-shear environment that is forecast, but we are quite skeptical of the mid 40s dewpoints in the NAMnest. HREF mean dewpoints are closer to 40, and the HRRR is in the mid 30s. Meanwhile, the RAP actually has lower 40s dewpoints paired with zero CAPE. Nevertheless, in the absence of the aforementioned worst-case scenario, deep inverted-v thermodynamic profiles could support wind gusts stronger than the background BL momentum transfer gusts with any shower or storm.

The cold front will usher in yet another seasonably cool and dry air mass that is forecast to persist through the first half of the weekend. Temperatures across the northern half of the state could fall to near freezing tonight, followed by near to below freezing temperatures statewide Saturday night as surface high pressure builds over the Canadian prairie provinces. The growing season officially begins today, so frost/freeze headlines may be necessary both tonight and on a much wider basis Saturday night. Despite the cool down to highs in the mid 50s to mid 60s on Saturday, afternoon humidity percentages in the 20s and northwest winds still breezy at around 15 to 20 mph could lead to near-critical fire weather conditions. A shortwave moving down the foothills of the Northern Rockies on Saturday could bring some light rain into the southwest corner of the state, but it more likely to remain dry. Sunday sees a slight warmup with much lighter winds as an amplified transient upper ridge pushes off the Rockies.

Ensemble guidance continues to advertise a potent shortwave/ clipper type system ejecting off the southern Canadian Rockies on Monday and digging into the Upper Mississippi River Valley Monday night. All ensemble clusters show the 850 mb thermal ridge over western North Dakota Monday afternoon, which could allow temperatures to climb above 80. There is also increasing ensemble consistency with this system now bringing medium chances for showers (and thunderstorms) to areas north and east of the Missouri River. Something to keep an eye on is that every cluster contains a narrow ribbon of CAPE on the order of a few hundred J/kg somewhere over central North Dakota Monday afternoon/evening with no lower than 50 kts of deep layer shear. Windy conditions are a given with this system, but there is still higher ensemble uncertainty on the magnitude of 850 mb winds for mixing potential. A brief, slight cool down in the post frontal air mass on Tuesday could be followed by temperatures more persistently above normal for the rest of next week, with ensemble clusters continuing to show near-equal probabilities for either a progressive, high-amplitude wave pattern or stagnant western CONUS ridging. For either synoptic pattern outcome, chances for rain at this forecast time range remain low. The biggest concern for next week is the potential for daily critical fire weather conditions, which is further discussed in the Fire Weather section below.

AVIATION /18Z TAFS THROUGH 18Z SATURDAY/

Issued at 1245 PM CDT Fri May 8 2026

Mainly VFR conditions expected through the forecast period. Some increasing mid to high level clouds will be found today, with chances for showers and thunderstorms later this afternoon through this evening. Most sites have PROB30 groups in TAFs for these thunderstorm chances. Some gusty winds are possible with any thunderstorm activity. Cold front will push through tonight, and may bring some brief MVFR to low VFR ceilings at times, especially in the KJMS area. Saturday then sees a mix of cloud cover with VFR and dry conditions generally expected. A gusty northwest wind will be found today becoming a steady northerly wind tonight into Saturday morning.

FIRE WEATHER

Issued at 1245 PM CDT Fri May 8 2026

Red Flag Warning now expanded across much of central North Dakota given higher than forecast winds over 20 mph and low humidity values in the teens and 20s. Currently much of the state is in a Red Flag Warning through this evening, while remaining areas in the north central and northeast are expected to be near critical fire weather conditions today through this evening. A weak cold front is still expected to move through this evening, slightly shifting winds to the north. Showers and a few thunderstorms are possible along this front through this evening. Any thunderstorms could bring gusty and erratic winds. Winds diminish yet remain a steady north wind tonight. Humidity recoveries will be much improved tonight with cooler temperatures moving in.

Lower dewpoints (than straight NBM) were blended into the forecast on Saturday, resulting in minimum humidity around 20 to 30 percent, lowest in the northwest quadrant of the state. The wind forecast for Saturday afternoon has slightly diminished from previous iterations, but still has northwest winds around 15 to 25 mph, strongest in the James River Valley area. Because the strongest winds and lowest RH are not forecast to greatly overlap, only near-critical fire weather conditions are being messaged for Saturday at this time.

After one day of much lighter winds on Sunday, a long stretch of enhanced fire weather concerns enters the forecast next week as temperatures are favored to be well above normal. Confidence is increasing that much of western North Dakota will experience critical fire weather conditions on Monday, with gusty southerly winds early in the day shifting to the northwest and becoming strong in the afternoon as humidity falls to near 20 percent. The risk for critical fire weather conditions more or less continues in western North Dakota through the work week, with daily gusty winds and minimum RH around 20 percent. Tuesday looks to be the least windy day in the west, but perhaps the windiest day for the eastern half of the state. A secondary area that shows up repeatedly in NBM guidance for critical fire weather next week is a portion of south central North Dakota bounded by Interstate 94, the James River, South Dakota, and Lake Oahe. Daily details for fire weather beyond the Monday/ Tuesday time frame remain uncertain, but there is undoubtedly increasing potential for a longer duration of high- impact fire weather, at least until fuels start to green up.

BIS WATCHES/WARNINGS/ADVISORIES

Red Flag Warning until 10 PM CDT /9 PM MDT/ this evening for NDZ001-002-009>011-017>023-025-031>037-040>048-050-051. Frost Advisory from 1 AM CDT /midnight MDT/ to 9 AM CDT /8 AM MDT/ Saturday for NDZ001>005-009-010-012-013-017>020-022-023- 025-055>058.