Williston, North Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

951
FXUS63 KBIS 211749
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
Issued by National Weather Service Grand Forks ND
1149 AM CST Thu Nov 21 2024

.KEY MESSAGES...

- Below average temperatures through the weekend with highs
  mostly in the 20s and 30s, and lows mostly in the single
  digits to teens above zero. Even colder temperatures possible
  to start next week, though uncertainty remains higher.

- A 60 to 90 percent chance of additional accumulating snow this
  weekend in the north, with lower chances south. There is a 50
  to 70 percent chance of at least 4 inches of snow mainly along
  and north of Highway 2 and especially west of Highway 281.

&&

.UPDATE...
Issued at 1142 AM CST Thu Nov 21 2024

Some sporadic light snow near Sloulin is causing some reductions
in visibility. Later this evening the southern portion of
Western North Dakota will start to clear out but will start to
redevelop throughout the day tomorrow.

UPDATE
Issued at 855 AM CST Thu Nov 21 2024

Lake effect snow and stratus continue over the central and south
central. Otherwise the forecast remains on track for today.

UPDATE
Issued at 609 AM CST Thu Nov 21 2024

Quick update to expand light snow shower mention south central.
Lake effect stratus and snow showers continue, pushing a bit
more east so expanded POPs for early this morning.

UPDATE
Issued at 536 AM CST Thu Nov 21 2024

The forecast remains on track.

&&

.DISCUSSION...
Issued at 352 AM CST Thu Nov 21 2024

Lake effect stratus and light snow is occurring south of Lake
Sakakawea, with Hazen reporting light snow. This should only
last for a few hours before ending as winds become light and
variable. Otherwise, dry conditions with highs ranging from the
low 20s north to the upper 30s southwest are on tap today. Lows
tonight will be mostly in the teens. These high temperatures
are around 5 to 10 degrees below average for this time of year,
while the lows are near to slightly below average. Weak energy
tonight will provide a 20 percent chance of light snow in the
far northwest, though any accumulations are likely to be a
dusting at most. Dry conditions with similar highs are expected
during the day Friday as well.

During the period from now through Friday, a ridge starts in
place over the Highs Plains and will stretch eastward over the
Central Plains. Upper low pressure off the Pacific will split
into two individual circulations, which will do-si-do around
each other. The parent low will then begin to reingest the
second circulation, and momentum from this upper low dance will
result in a third low pressure center splitting off, spiraling
through the Rockies, and passing through south central
Canada/North Dakota as a clipper system.

Initially, as aforementioned ridging over the Central Plains
begins flattening Friday night, light snow off WAA is possible
mainly in the northwest and then expanding into the north
central Saturday. However, as the clipper begins to organize and
move through the area, snow chances increase Saturday night
through Sunday. At this time, there is now a 60 to 90 percent
chance of accumulating snow in the northern half of the state
Saturday night through Sunday. In addition, there is a 50 to 70
percent chance of 4 inches or more of snow mainly along and
north of Highway 2 and especially west of Highway 281. Winds
are not progged to be anywhere near as strong with this system
as the last system. However, breezy to windy conditions are
still in the forecast during the day Sunday.

Beyond Sunday night, multiple weak shortwaves are possible next
workweek, though the bigger story will be continued well below
average temperatures. Highs for next week are favored to be
mostly in the teens and 20s with lows mainly in the single
digits on either side of zero, though predominantly on the
positive side. That said, NBM 25th/75th ensemble forecast
spreads remain high for next week with plenty of room to be 5 to
even 10 degrees warmer or colder than in the present
deterministic forecast.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1142 AM CST Thu Nov 21 2024

Cloud ceiling are slowly moving in from the West but will stay
between 7,000ft and 10,000ft. Some clearing mainly I-94 and
south is expected to occur this evening however some fog
development in those areas make occur as low level moisture may
become trapped under the area of high pressure. Under the area
of high pressure winds are likely to become variable at 4 knots
or less. Depending on whether or not the clouds clear out will
determine if the fog will develop in these areas of clear skies.


&&

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

&&

$$

UPDATE...MM
DISCUSSION... Telken
AVIATION...MM