textproduct: Bismarck

KEY MESSAGES

- Mainly dry conditions expected from Tuesday through the rest of the week.

- Below average temperatures continue through the first part of the week, then a warming trend develops.

UPDATE

Issued at 938 PM CDT Mon Apr 27 2026

Modified sky cover and hourly weather elements based on latest obs, otherwise there were no major changes to the forecast for tonight.

UPDATE Issued at 639 PM CDT Mon Apr 27 2026

Some lingering very light rain or snow south, and should dissipate over the next couple of hours. POPs were adjusted for this. Other main updates were to sky cover based on latest satellite imagery, and winds based on latest observations and trends. Allowed the Wind Advisory to expire with peak gusts below 40 mph now across the James River Valley. Overall quiet weather expected tonight.

DISCUSSION

Issued at 229 PM CDT Mon Apr 27 2026

Shortwave trough currently over eastern SD will lift further off into the Upper Midwest tonight, with the next major shortwave coming around the Hudson Bay low moving into the Rockies. Light radar returns continue over southern portions of the forecast area, but should clear out as the eastern shortwave continues to pull away. Fairly tight pressure gradient will continue over the southern James River Valley into the early evening before we lose the good mixing and the system pulls further east, so will keep the wind advisory going. Should start to see clouds clear out for a period overnight as high pressure builds into the Western Plains. Tomorrow, the Rockies shortwave moves out into the Plains, although the bulk of the vorticity and precipitation looks like it will be to our south. However, several CAMs show some shower activity across eastern MT and encroaching into far western ND. The model soundings have a pretty good dry layer at the surface so uncertain how much will actually reach the ground, but included some very low POPs in far northwestern ND for tomorrow afternoon.

Northwesterly flow aloft with a few weak embedded shortwaves continues through the end of the week and into the weekend. A few of these minor ripples could bring some low precip chances, but they are unlikely to be high QPF producers under northwest flow. ECMWF EFI is not showing much of a wet signal, and NBM probabilities of over a tenth of an inch of rain are under 20 percent. Temperatures should moderate back up to near or above seasonal averages later this week as 500mb heights rise. Some of the ensemble members showing another stronger trough digging in by day 7 that could bring some colder temps again, but several other clusters keep higher heights over the Plains, so confidence is low.

AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/

Issued at 639 PM CDT Mon Apr 27 2026

MVFR-low VFR ceilings continue for KDIK and KJMS, with cloud cover dissipating early this evening. All sites will be VFR for the remainder of the 00Z period, with some VFR diurnal CU for Tuesday daytime. North-northwest winds will diminish by 02Z all sites, remaining out of the northwest through the period.

BIS WATCHES/WARNINGS/ADVISORIES

None.