515
FXUS63 KBIS 250038
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
638 PM CST Sun Nov 24 2024

.KEY MESSAGES...

- Below normal temperatures will continue through next week.
  The coldest period is forecast over the Thanksgiving Holiday
  weekend, when morning wind chill temperatures will approach 30
  below zero some areas.

- A clipper system could bring light accumulations across the
  state Tuesday and Wednesday.

&&

.UPDATE...
Issued at 626 PM CST Sun Nov 24 2024

Light snow continues to shift to the east of the area, with
a few flakes lingering over eastern Dickey County. This will
continue to move out over the next few hours. With that said,
have increased clouds in the forecast over much of the area.
Although clearing is developing, especially over the northwest,
clouds still remain overcast over southeastern portions of the
area.


&&

.DISCUSSION...
Issued at 228 PM CST Sun Nov 24 2024

An upper level low continues to move across southern
Saskatchewan into southern Manitoba placing western North
Dakota in the dry slot. Dry air wrapping around the upper low
and subsidence aloft is mixing breezy conditions across the
west. Dry air continues to drive the low stratus over central
North Dakota eastward. Dry air intrusion has also ended freezing
drizzle across much of central North Dakota while freezing
drizzle continues eastern North Dakota and portions of the James
River Valley, but will clear up later this evening. Some snow
continues to move up from the southwest and could clip the James
River Valley this evening. Overnight lows are forecast to drop
down near 0 to the single digits. This due to strong surface
high pressure and a strong Arctic airmass settling in the
region. Temperatures are already in the low teens in the
northwest as surface high pressure builds.

Tomorrow, high temperatures may only climb out into the lower
teens north to 20s south. The upper level pattern will lock
into northwesterly flow as high pressure builds out over Western
CONUS and low pressure stalls out over the Great Lakes. This
will keep the upper level pattern over the Northern Plains in
northwesterly flow. Thus, opening the door for a few weak upper
level waves resulting in light snow throughout the week. The
first of these waves is forecast to move in late Tuesday into
Wednesday. The 25th to 75th snow forecast currently has 1 to 2
inches possible with locally higher amounts possible. Another
weaker wave could move through the region Thanksgiving.

Temperatures are forecast to remain in the teens up north and
the 20s down south through the week. These below normal
temperatures will linger through weekend as another burst of
cold air move trough the region and the end of the week. This
will lead to cold temperatures persisting around Thanksgiving.
Low temperatures are forecast to drop down to 15 to 20 below up
north to 5 below to 0 down south Friday morning. Wind chills
could reach 30 below across the state. These cold temperatures
will persist into the weekend.

The pattern begins to look a bit more uncertain next week. If
the upper level ridge shifts further east that would result in
"warmer" temperatures or if the ridge remains out west colder
temperatures will persist. The warmer solution has about 65
percent chance while the colder solution is around 35 percent
chance. This is reflected in the NBM 25th-75th which has over a
30 degree spreed for high temperatures early next week. Even
though there is a 30 degree spread, the 25th percentile trends
warmer at the beginning of next week showing a rebound in
temperatures.

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 626 PM CST Sun Nov 24 2024

Localized IFR with areas of MVFR ceilings will continue over
parts of south central North Dakota including the KJMS terminal
this evening, with conditions improving overnight. Elsewhere,
most locations will remain VFR, though localized MVFR cloud
cover may pass by from time to time overnight.

&&

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

&&

$$

UPDATE...JJS
DISCUSSION...Johnson
AVIATION...JJS