Bismarck, North Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

185
FXUS63 KBIS 231809
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
1209 PM CST Sat Nov 23 2024

.KEY MESSAGES...

- There is a chance (30 to 60 percent) of light accumulating
  snow this weekend across the north, with chances decreasing
  towards the south. Any snow accumulations are expected to
  remain below one inch.

- Below average temperatures are expected this weekend and
  through next week. The coldest period is forecast over the
  Thanksgiving Holiday weekend.

- While no major storms are forecast for next week, weather
  disturbances moving through the region will bring chances for
  light snow at times.

&&

.UPDATE...
Issued at 1145 AM CST Sat Nov 23 2024

Snow continues to move in across the northwest. Light snow has
been observed in eastern Montana. Fog continues to weaken but
low stratus continues across the west. No updates are needed at
this time.

UPDATE
Issued at 848 AM CST Sat Nov 23 2024

Patchy fog continues to linger across the southwest. This had
lead to some light frost build up. Expanded and extended the
patchy for the southwest to match current trends. Visibility
reductions remain minimal with only a site or two dropping down
to half a mile. Other than that no updates are needed at this
time as the forecast remains on track.

UPDATE
Issued at 534 AM CST Sat Nov 23 2024

Mainly updated for Aviation Discussion (below). Did tweak sky
cover to better match latest satellite imagery. All other
weather elements on track this morning.

&&

.DISCUSSION...
Issued at 410 AM CST Sat Nov 23 2024

Currently, broad upper level ridge building east into the Great
Plains, with another deep upper level trough developing over the
west coast. Embedded impulse which brought some light
accumulating snowfall earlier Fri evening and earlier this
morning is tracking off to our east, with diminishing forcing
across the local region as the upper ridge axis approaches and
as a ridge of sfc high pressure builds southward into central
ND. Resultant radar returns have indeed shown a downward trend
in activity the past few hours.

Upper ridge moves slowly east across the Northern Plains today,
as a strong upper level jet rounds the base of the
aforementioned upper trough and lifts east-northeast into the
Northern Rockies. Embedded mid level energy ejecting out of the
upper trough will organize as it interacts with left exit
region jet dynamics, morphing into a closed low over far south
central Canada Sat night into Sunday over the southern
provinces of Saskatchewan and Manitoba. The projected track of
the mid level low and its associated sfc trough will keep the
bulk of QPF/accumulating snowfall north of the US/Canadian
border, with NBM and WPC guidance continuing the downward trend
in accumulations, now mostly less than one inch through Sunday
across my north.

CAA on Sunday on the back side of the sfc trough will see breezy
northwest winds, with daytime highs Sunday trending cooler from
today, then even colder for Monday with continued CAA, with
forecast highs only in the teens and low 20s. Overnight lows Sun
night will be in the single digits above, with wind chills in
the single digits and teens below zero with a steady northwest
breeze. Ridge of sfc high pressure settling over the state then
looks to bring even colder overnight lows for Mon night/Tues
AM, with lows in the single digits above and below zero, though
with light winds.

Ridge of high pressure building over the eastern Pacific and a
long wave trough over eastern North America will then result in
a dominate northwest flow aloft through next week and the
Thanksgiving Holiday weekend. This pattern will maintain below
average temperatures over the Dakotas, especially as we
progress later in the week. Ensembles and NBM are still showing
a couple of cold air surges, one around Thanksgiving Day and
another over the weekend. NBM MaxT/MinT 25/75 percentile spreads
have decreased, leading to higher confidence in the cold through
Friday of next week (mean NBM MaxT values are 15-20 degrees
below average for highs, with average highs for the local area
in late Nov right around 30F). Multiple shortwaves will also
move through the region next week, each bringing the chance for
some light snow and a period of elevated winds as associated
frontal boundaries push through. With sub-zero temperatures
forecast during the nighttime/morning hours late in the week,
will need to keep an eye on wind chill temperatures, as they
are currently projected to range from 10 below to 30 below zero
Thursday, Friday, and Saturday mornings.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1145 AM CST Sat Nov 23 2024

MVFR conditions will persist across the state for all terminals.
Snow continues to move into the northwest today and across the
northern half of the state tonight. Highest probability for snow
is along the international border. Low stratus has been
observed moving in behind the snow in eastern Montana and
forecast models have low stratus moving into the state this
evening through much of tomorrow. This will result in IFR
conditions and possible FZFG and BR early tomorrow morning.

&&

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

&&

$$

UPDATE...Johnson
DISCUSSION...NH
AVIATION...Johnson