textproduct: Bismarck

KEY MESSAGES

- Periodic showers and thunderstorms across the west today, moving eastward tonight. Periodic shower and thunderstorm chances will continue through Tuesday.

- The threat for severe weather is overall low today through at least the middle of next week, although an isolated strong storm is possible Monday and Tuesday.

- Temperatures will remain below average through the middle of next week, with a slight warm up favored for the end of next week.

UPDATE

Issued at 1246 PM CDT Sun Jun 21 2026

Showers continue to very slowly enter western North Dakota. However, with a lack of instability, lightning hasn't been observed in eastern Montana over the past couple hours. Instability may increase to some degree later this afternoon or evening potentially resulting in isolated thunderstorm development in western and north central North Dakota. All in all, the forecast remains on track.

UPDATE Issued at 844 AM CDT Sun Jun 21 2026

Showers are present in the far southwest, though overall precipitation has been light so far. Otherwise, radar echoes in eastern Montana continue to gradually work eastward. The eastern PoP extent may be a little on the high end this morning, but will leave as-is for now and see how things evolve over the next few hours.

UPDATE Issued at 645 AM CDT Sun Jun 21 2026

Limited updates needed this morning. Low pressure system in SD is brining some showers to southwestern portions, with thunderstorms just across the border in MT and SD. Meanwhile showers and thunderstorms in eastern MT have developed from a second low in souther Canada. These will slowly move eastward and may impact western ND later this morning or more likely this afternoon. Made some minor adjustments to PoPs based on the current radar trends, otherwise the forecast remains on track.

DISCUSSION

Issued at 359 AM CDT Sun Jun 21 2026

Two areas of low pressure will bring some unsettled and cooler weather to the area today. The first low pressure system currently in northwestern SD has returned showers to the southwest with abundant cloud cover elsewhere early this morning. Precipitation associated with this low could linger across these southwestern portions through this morning, then diminish once the low moves southeastward into SD. Influence from the second area of low pressure could then take over this afternoon through this evening and bring another round of showers and perhaps some thunderstorms to the west. An axis of instability will set up with this second low in eastern Montana, with some modest shear. Right now it does appear this instability does not make it very far into western ND, thus the threat for severe weather is low today through this evening. The mentioned cloud cover will bring cooler highs today, with 60s west to the low to mid 70s east. A breezy at times southeast wind will also linger through today. Tonight, the initial push of precipitation associated with the second low will push across the state, with perhaps an isolated thunderstorm. Lows tonight will generally be near 50 degrees. Monday, broad upper low will move more into the region, continuing unsettled weather and below normal temperatures. A weak warm front may set up during the day Monday, followed by passage of a weak cold front Monday night. A favorable jet location could also help increase chances for showers and thunderstorms Monday. SPC has maintained general risk for thunderstorms Monday, although there is some modest to high shear and modest instability Monday afternoon and evening. Thus an isolated strong to perhaps severe storm is possible. Hail would likely be the main threat given low DCAPE. Pwats over an inch would indicate some locally heavy rain is also possible. With this weak warm front could be slightly warmer temperatures in the 70s on Monday. Widespread showers and thunderstorms will linger through Monday night, with lows in the upper 40s to lower 50s. Slightly cooler and breezy northwest winds are expected for Tuesday after passage of a cold front. Broad upper low could provide for some afternoon and evening showers and thunderstorms across much of the area on Tuesday. Weak instability with lingering modest to high shear could once again bring an isolated strong to severe storm. The higher chances for these stronger storms will generally be in eastern ND where SPC currently has a Marginal Risk for severe weather on Tuesday. Precipitation should diminish Tuesday night, with cooler lows in the 40s to lower 50s.

Wednesday through Friday, a mix of weak ridging and west to northwest flow are generally forecast. This brings mainly dry conditions at least initially, with perhaps some increased chances later in the work week. Temperatures will go on a slow warming trend with highs near 80 by the end of the work week. Timing of the next broad trough could impact weather for next weekend. Current forecast has increase chances for showers and thunderstorms as a result especially later in the day Saturday through Sunday. Temperatures will continue to be near seasonable normals to start the weekend, although may cool slightly once the mentioned trough moves through. SPC currently does not have any severe outlooks in ND for days 4 through 8 although makes note in the text discussion of the potential for severe weather returning in the northern plains from the mentioned return to trough pattern. CSU-MLP is also picking up on some severe weather potential for the upcoming weekend. Timing of this trough will greatly determine the location of severe weather during this time period and will be worth monitoring going forward.

AVIATION /18Z TAFS THROUGH 18Z MONDAY/

Issued at 1246 PM CDT Sun Jun 21 2026

Showers are slowly entering western North Dakota with light rain now observed at KXWA and the Bowman radar indicating light rain could begin at KDIK any moment now. MVFR ceilings and visibility have been observed with these showers in eastern Montana, and could impact western ND as well. Showers will likely end in the southwest later this afternoon or evening, but persist in the north through the night tonight, possibly impacting KMOT as well. Embedded isolated thunderstorms are possible later this afternoon and evening.

BIS WATCHES/WARNINGS/ADVISORIES

None.