Williston, North Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

567
FXUS63 KBIS 260847
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
347 AM CDT Sun Jul 26 2026

.KEY MESSAGES...

- Heat bursts associated with dying thunderstorms may produce
  locally strong winds across southern North Dakota early this
  morning.

- Very hot conditions today, with dangerously high temperatures
  and heat index values around 100 to 105 degrees.

- The combination of hot, dry, and breezy conditions today may
  cause near-critical fire weather conditions in parts of
  western and central North Dakota.

- The very hot temperatures may continue into Monday southwest,
  with a slight drop in temperatures elsewhere. The rest of the
  week remains hot with highs mostly in the 90s, but with some
  reading above 100 degrees possible in southwest North Dakota.

- Widespread precipitation chances are low until midweek, when
  there is a 30 to 50 percent chance for showers and
  thunderstorms across the forecast area.

&&

.DISCUSSION...
Issued at 347 AM CDT Sun Jul 26 2026

This morning, an area of showers and thunderstorms was ongoing
in far southwest North Dakota along the state border. The main
concern with this area of convection would be isolated strong
winds, as the very warm and dry air mass is supportive of heat
bursts. Elsewhere, fog has been developing across parts of the
James River Valley and up through much of north central North
Dakota, and will continue to monitor in case any additional
products are needed for this. High-res guidance has not done
well already catching on to the reduced visibilities, but would
expect at least patchy fog to persist into mid morning.

Another hot and mostly dry day is in the forecast today, as the
upper ridge axis continues to extend over the north central
CONUS with a low-level thermal ridge aiding in bringing well
above average temperatures to the state. Forecast highs range
from the lower 90s along the International Border to the 100 to
105 range across the southwest and south central. A Heat
Advisory remains in effect for most of the forecast area, with
the exception of the northern two tiers of counties.

Other forecast concerns today include a low chance for a few
showers and thunderstorms today in the Turtle Mountains area as
a weak surface low tracks along the International Border, and
patchy near-surface smoke across the southwest and south
central. HRRR smoke model hasn`t been performing the best the
last day or two but is very confident in a plume of thick smoke
accompanying the aforementioned surface low and associated
frontal boundary, so wanted to add it into the gridded forecast.
We also continue to mention near-critical fire weather
conditions across most of western and parts of central North
Dakota, with a northwest breeze today and minimum relative
humidity in the lower to mid teens for areas south and west of
the Missouri River.

Temperatures "cool down" a few degrees for the first half of the
work week, but forecast highs are still in the 90s to around 100
degrees F. Chances for widespread precipitation are low Monday
and Tuesday, although can`t rule out a few isolated showers and
thunderstorms associated with embedded impulses passing over
the ridge axis. More substantial blended PoPs emerge on
Wednesday as ensemble guidance is more confident on a stronger
wave moving across the Dakotas. Temperatures to end the week
cool down a bit further into the upper 80s to upper 90s,
although latest NBM percentiles show potential for warming up
slightly for next weekend. NSSL machine learning is currently
favoring Wednesday and Thursday for the highest likelihood of
severe thunderstorms, but any day for the next week will have
some potential for any storms that can develop to be at least
strong. There finally starts to be a signal for closer to normal
temperatures as we get past the first few days of August.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1252 AM CDT Sun Jul 26 2026

VFR conditions generally expected at all terminals through the
06Z TAF period. A few showers and an isolated thundershower are
possible across southwest North Dakota overnight, including
KDIK, although confidence in impacts and timing was too low to
include with this update. Some patchy fog is possible over
portions of the James River Valley overnight as well. Light and
variable winds overnight will become northwesterly through the
day Sunday, with gusts up to 25 knots possible.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 9 PM CDT /8 PM MDT/ this evening for
NDZ017>020-022-023-025-031>033-035>037-040>044-046>048-050-051-
057>062.

&&

$$

DISCUSSION...Jones
AVIATION...Jones