163
FXUS63 KBIS 281953
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
253 PM CDT Tue Jul 28 2026

.KEY MESSAGES...

- Hot and smoky conditions continue through at least the middle
  of the week, with highs around 90 to 100.

- Medium to high chances (40 to 70 percent) for showers and
  thunderstorms Wednesday afternoon through Thursday. Some
  storms could be severe, especially in the west half of the
  state Wednesday afternoon and evening.

- A little cooler Thursday and Friday, but hot conditions could
  return for the upcoming weekend.

&&

.DISCUSSION...
Issued at 132 PM CDT Tue Jul 28 2026

Currently, scattered showers and isolated thunderstorms
continue to propagate east from eastern MT into western ND.
Instability is limited here and CIN continues to increase over
western ND this afternoon, so the threat for thunderstorms
remains low here. Over eastern ND, instability is much more
concerning with 2500 J/Kg of MLCape situated over the northern
James River Valley with little capping and convective
temperatures in the low to mid 90s (current temps around 90).
Forecast HRRR soundings indicate a marginally severe potential
should convection develop. A limiting factor is building upper
heights and the lack of forcing for ascent this afternoon,
combined with a general drying of the lower boundary layer.
Cams have been back and forth as whether or not to develop
convection here today. Currently, a couple of the CAMS are
showing at least an attempt at convection, while a majority
remain dry. If we would see convection from the Turtle Mountains
into the James River Valley a stronger to marginally severe
storm can not be ruled out. For most, this afternoon and tonight
will be dry.

Wednesday will be another hot day across western and central
ND. Afternoon high temperatures range mostly from the mid 90s to
near 103, with the hottest temperatures over the west central
and southwest. Heat Advisory criteria may be met, generally in
areas south and west of the Missouri River. However, the areal
extent of advisory criteria heat indices is low. There are also
some concerns regarding cloud cover from convection, limiting
temperatures if it develops earlier in the day. In addition, the
southwest portion of the state will probably see some of the
lower dewpoint in the area Wednesday afternoon, limiting heat
indices to below the actual air temperatures. Will let later
shifts monitor for possible highlights tomorrow.

Another concern Wednesday will be the threat for severe storms.
SPC has upgraded pretty much the western half of the state to a
slight chance (level 2 out of 5) for severe storms. In general,
it looks like storms will develop over eastern Montana Wednesday
afternoon and move into western ND through early evening.
Damaging winds will be possible given the inverted V soundings.
Large hail will also be possible given the steep lapse rates
and increasing winds aloft. We will message the same hazards as
the previous forecast, golfball sized hail and 70 mph winds.
Storm mode looks to be more linear north with bulk shear vectors
more parallel to the surface trough, while they are more
perpendicular south, indicating more of a supercell threat.
With a surface low over eastern Montana and strong surface
heating, there could be a window of opportunity for a tornado
early on, in the northwest where LCL heights will be more
favorable. Cams are pretty consistent in convection not holding
together as it moves into a less favorable environment over
central ND. This then muddles the picture for potential
convection on Thursday. There is currently a marginal risk for
severe storms across most of the forecast area on Thursday. We
will keep messaging general for Thursday at this time as a lot
will depend on how things evolve tomorrow. Bulk shear definitely
looks to be weaker and Cape also looks like it may be lower
with more cloud cover remaining over a good portion of the
forecast area.

Thursday and Friday will be cooler (relatively) with highs in
the mid 80s to lower 90s Thursday, and mid 80s to mid 90s
Friday. We then warm back up over the weekend with some 100
degree readings possible once again Saturday and especially
Sunday. Heat headlines may once again be in play. Fire weather
concerns may also be heightened by Sunday as grasses continue to
cure and we see stronger southerly winds develop Sunday
afternoon. Another cooldown does look to be in store for at
least the beginning of next week.

&&

.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 1155 AM CDT Tue Jul 28 2026

VFR conditions are expected through the 12Z TAF period.
Generally light and variable winds through the period 12 knots
or less. Isolated thunderstorms can not be ruled out, but too
much uncertainty to even include a PROB30 at any TAF site.
Patchy fog can not be ruled out either late tonight into
Wednesday morning but too much uncertainty to include any fog at
this time.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION...TWH
AVIATION...TWH