textproduct: Bismarck

KEY MESSAGES

- Precpitation will diminish from west to east through the day.

- Strong winds expected in the southern James River Valley today.

- 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.

DISCUSSION

Issued at 400 AM CDT Mon Apr 27 2026

Southwesterly flow is found over the northern Plains this morning as a closed low over the southern Canadian Prairies is progged to slowly slink off toward Hudson Bay through the day today. At the surface, a low pressure system moving across eastern South Dakota into southern Minnesota is promoting precpitation across much of western and central North Dakota this morning. While mainly falling as rain, some snow is found along the northwestern extent of this precipitation as cooler air moves in behind this system. Chances for precpitation will diminish from west to east this morning and through the early afternoon as the inciting low pressure system moves off into the Great Lakes Region, and as high pressure moves in from the northwest through the day today. Additional QPF this morning through this afternoon is expected to be fairly light, with low to medium chances to exceed 0.10" an inch of precipitation found across the far south and the James River Valley.

With the decent pressure gradient draped across the northern Plains between the incoming high pressure center and the exiting low pressure system, breezy to windy conditions are expected this afternoon, though the lack of strong winds aloft will limit the overall potential. Portions of the southern James River Valley are expected to approach Wind Advisory criteria late this morning into this afternoon, with sustained speeds around 25 to 30 MPH and isolated gusts as high as 45 MPH, especially when and where rain is falling. As such, a Windy Advisory will be in effect for portions of south central North Dakota from 7 AM CDT this morning through 7 PM CDT this evening. Winds should diminish fairly quickly in the late afternoon and early evening as the the low moves further to the northeast and the gradient relaxes.

Otherwise for today below normal temperatures are expected to continue across the northern Plains, reinforcing with the cooler air moving in behind the low pressure system. Low temperatures this morning are from the mid 20s west to the upper 30s east, while highs this afternoon are forecast broadly in the 40s to lower 50s. Mostly cloudy skies are expected to diminish through the afternoon and evening as high pressure becomes more established over the area.

A somewhat messy but broadly north-northwesterly flow regime is then expected Tuesday through the remainder of the workweek as a transient ridge makes landfall into the Pacific northwest. Mainly dry weather and warming conditions are anticipated through this period, though the occasional shortwave perturbation could promote low chances (10 to 30 percent) for rain each day across our south. With this warming trend, highs broadly in the 50s are expected Tuesday through Thursday, before peaking into the 60s and lower 70s this weekend. Looking further ahead, ensemble members broadly advertise a transition to more strictly northwesterly flow late Sunday into early next week as the transient ridge is absorbed into the general flow pattern. With this, we could expected at least some chance for precipitation across the area some time during this period, though there is no strong signal for any real rainmakers at the time of this forecast cycle. Cluster analysis reveals that the most ensemble members advertise at least some light precpitation across much of the forecast area by late Sunday into Monday, though there is some disagreement on whether or not this will be fairly widespread (60 percent of members), or more restricted to our far southern counties (40 percent). In either scenario, high temperatures would be expected to be a little cooler compared to the preceding weekend, near to slightly below normal for this time of year.

AVIATION /06Z TAFS THROUGH 06Z TUESDAY/

Issued at 400 AM CDT Mon Apr 27 2026

Precpitation will promote MVFR to IFR ceilings across portions of western and south central North Dakota overnight, slowly improving from northwest to southeast through the day Monday. While much of this precpitation is expected to fall as rain, light snow is possible over the west, which could promote MVFR to IFR visibilities when and where it falls. VFR conditions are generally expected to persist across the north central. North to northeast winds are expected to strengthen overnight through this morning, becoming gusty over portions of south central North Dakota late Monday morning through the afternoon, before diminishing through the early evening.

BIS WATCHES/WARNINGS/ADVISORIES

None.