textproduct: Bismarck

KEY MESSAGES

- Cooler temperatures remain today, followed by a strong warming trend through the weekend.

- Isolated severe thunderstorms are possible Thursday afternoon into Thursday evening.

- Very hot this weekend and early next week, with daily high temperatures and maximum heat indices around 95 to 105.

UPDATE

Issued at 1239 PM CDT Wed Jul 8 2026

Clusters of light rain showers continue across the northwest and north central. Otherwise the going forecast looks good.

UPDATE Issued at 935 AM CDT Wed Jul 8 2026

Continued broad, low PoPs across parts of the north and central to account for widely scattered showers this morning. Otherwise, going forecast looks good for today.

UPDATE Issued at 628 AM CDT Wed Jul 8 2026

Isolated showers continue over portions of northwest and central ND early this morning. Made some minor adjustments to pops to account for this. Stratus/fog has not been as forecast as was feared, but low ceilings and patchy fog do remain in a few areas this morning. Overall few changes needed for the early morning update.

DISCUSSION

Issued at 339 AM CDT Wed Jul 8 2026

A broad quasi-zonal upper level flow will continue over the region through the remainder of the workweek, followed by significant upper level ridging over a large portion of the western and central Conus. This could bring a significant prolonged heatwave to western and central ND this weekend into early next week.

Currently, the latest satellite imagery show a number of waves moving through the broad upper level flow. Latest radar shows an area of isolated showers situated over northwest ND. Patches of low stratus/fog have been noted under breaks of high level cirrus, but as of yet nothing widespread. As we head into the early morning hours guidance suggests, and it seems reasonable, given the low T/Td spreads we will see an increase in stratus and fog. Guidance does favor western and southern portions of the forecast area.

For today, forecast soundings suggest instability will remain weak this morning. However with an approaching shortwave currently indicated over eastern Montana, there may be enough forcing to keep a mention of showers in the forecast. Soundings dry out this afternoon and mostly dry conditions are expected. Afternoon convection off the higher terrain in Wyoming and southeast Montana should remain south and east of the forecast area later today, but an evening thunderstorm can not be ruled out in the far southwest. Another wave tracking along the International Border may fire convection over central Montana, and if it holds together could move into far western ND towards daybreak Thursday. The severe threat by this time would be low.

On Thursday, the aforementioned wave tracks across the state and a surface trough lingers over the area. It will become very unstable over western ND Thursday afternoon with RAP forecast MLCAPE values around 3000 J/Kg. Bulk shear is marginal, ranging from 25 to 35 knots. Forcing for ascent will be modest with only weak impulses moving through a slowly building ridge. If there is enough forcing to overcome some low level capping, isolated strong to severe thunderstorms will be possible. SPC has maintained a marginal risk (level 1 out of 5) for severe storms across most of the forecast area Thursday. Shear vectors are not completely perpendicular to the surface boundary but enough so that a supercell thunderstorm can't be ruled out. The main threats Thursday afternoon and evening would be large hail to the size of golf balls and 60 mph winds.

After Thursday, attention shifts to the potential for a prolonged heat threat through the weekend and into early next week. Friday will see daytime highs climb into the upper 80s to mid 90s, but the most impactful heat will be over the weekend and early next week. Daytime highs of 90 to 100 on Saturday, and 95 to 105 Sunday may necessitate the need for a long term Heat Hazard, especially since overnight low temperatures remain at or above the 70 degree mark. At this time, Sunday looks to be the most oppressive day with heat indices above 100 degrees across most of the forecast area, and up to 108 degrees in a few areas. However if you consider the HeatRisk and WBGT, a case could be made for a long term hazard encompassing Saturday through Monday, given the warm overnight lows. We still have a while to ponder, but if current forecast trends hold, it will definitely be a very hot weekend. With a lot of outdoor events going on, we will definitely be increasing our heat related messaging.

The oppressive heat should limit thunderstorm activity over the weekend.

AVIATION /18Z TAFS THROUGH 18Z THURSDAY/

Issued at 1239 PM CDT Wed Jul 8 2026

VFR with a few areas in the south central of BKN MVFR CIGs this afternoon. Winds will be southeasterly 5 to 10kts, calming after sunset.

BIS WATCHES/WARNINGS/ADVISORIES

None.