textproduct: Bismarck

KEY MESSAGES

- Medium to high chances for light rain from the Turtle Mountains south through the James River Valley and eastward.

- Temperatures favored to remain near to slightly above average until late next week.

- High chances for showers and thunderstorms Sunday evening through Monday night for all but northwest North Dakota.

DISCUSSION

Issued at 1259 PM CDT Fri Sep 25 2026

Currently, low cloud remains across central and eastern North Dakota, with only some high clouds in the west. Temperatures were mainly in the 60s , except low to mid 70s under the more abundant sunshine out west.

For tonight, most guidance suggests that the stratus will work back to the west as a south to southeast return flow strengthens over North Dakota ahead of a surface low situated over western Canada. We do not anticipated widespread dense fog like we have seen the past two mornings because of the increasing surface gradient. However, some patchy fog can not be ruled out. Guidance has been suggesting southern portions of the forecast area, and added a mention of patchy fog later tonight into Saturday morning. Latest guidance also keeps the mention of rain from the Turtle Mountains into the James River Valley and eastward late this afternoon through tonight. There is a timeframe later this evening where low pops do extend back to near the Missouri River in the south central, before shifting back to the east after midnight. With the saturated lower layers and some weak low level omega, we could see some patchy drizzle extending west of the main precipitation area, to the Highway 83 corridor. Will monitor, but too uncertain to add a mention at this time. On Saturday, the cold front associated with the Canadian low pressure system swings west to east through the forecast area. This will clear out the low stratus and shift winds from southerly to northwest. Although it won't be much colder behind the front, it will be noticeably drier. Highs will be mainly in the upper 60s to mid 70s across the forecast area Saturday. Look for breezy southerly winds central early in the day and breezy northwest winds over western ND late morning and into the afternoon. High pressure builds over the area Saturday night through a good portion of the day Sunday. Look for lows in the lower 40s to lower 50s Saturday night and highs on Sunday in the mid 60s to lower 70s.

Another upper level trough then looks to impact our weather later in the day Sunday, through Monday night. A lead shortwave propagating through a northern California upper trough will induce cyclogenesis over the central High Plains, with an inverted surface trough extending into the northern Plains by early Monday. A northern stream wave may induce convection over the Mondak region late Sunday, and into Sunday evening. Strong bulk shear will be situated over the area. MLCAPE of 500-1000J/KG lifts from South Dakota into southwest ND Sunday afternoon. Currently we have a general thunderstorm risk form SPC Sunday. A stronger storm can not be ruled out with some hail the most likely threat due to the likely elevated nature of the storms. The entire system spreads east Sunday night through Monday. Monday afternoon into early Monday may be another potential for stronger storms as strong bulk shear weakens a little but instability maybe greater from the south central into the James River Valley. As mentioned in the previous discussion, anomalously high Precipitable Water values and possibly some training storms, may result in efficient rainers with locally heavy rainfall Sunday night through Monday night as the system works it's way east across the forecast area.

We then dry out, at least for a while with a quasi-zonal flow over the region and temperatures remaining near normal with highs in the 60s to lower 70s and lows in the 40s through the middle portion of the workweek.

AVIATION /12Z TAFS THROUGH 12Z SATURDAY/

Issued at 1158 AM CDT Fri Sep 25 2026

Widespread stratus continues to lift over central ND with mainly MVFR ceilings, but a few IFR ceilings do remain. Expect a gradual improvement early this afternoon with areas west of a lint from Bismarck to Bottineau lifting to VFR. Areas to the east may remain MVFR through the day and tonight. In western ND expect VFR conditions this afternoon as the stratus should hold off for now. Tonight, expect stratus to expand back westward with all TAF sites and most, if not all of ND seeing MVFR to IFR ceilings, with perhaps a few areas see LIFR ceilings. At this time we do not think that fog will be as prevalent as the past few nights. Areas with cloud cover will see ceilings lower tonight but stratus is favored over fog. Farther west, where low clouds have yet to develop, there could be some patchy dense fog develop, but southerly winds are expected to increase through the day today, remaining breezy to windy tonight, thus the fog potential seems to be limited, with lower stratus favored here as well. Will certainly need to monitor though. Southerly winds do remain breezy through the night across the forecast area, then beginning around 12Z Saturday, a cold front will move west to east, shifting winds to the northwest and clearing the low stratus. By 18Z western ND should be clear from the low stratus, with low clouds remaining over central ND. Shower activity is expected over eastern ND tonight into Saturday morning, mainly for areas along and east of the Turtle Mountains through the James River Valley.

BIS WATCHES/WARNINGS/ADVISORIES

None.