Bismarck, North Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

041
FXUS63 KBIS 171944
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
244 PM CDT Thu Apr 17 2025

.KEY MESSAGES...

- Isolated rain and snow showers are possible (20% chance)
  tonight through Friday.

- Windy and colder this afternoon and Friday with highs mainly
  in the 40s. The strongest winds will be this afternoon in the
  James River Valley.

- Trending warmer for the weekend and the start of next week.

- Widespread chances for precipitation (30 to 60 percent) return
  Monday and Tuesday.

&&

.DISCUSSION...
Issued at 244 PM CDT Thu Apr 17 2025

This afternoon, a closed low was analyzed in the central Canadian
Prairies, with a secondary low over the Southern Rockies. At the
surface, a deep low was moving into southern Minnesota, with
scattered showers and thunderstorms circulating around the center of
the low. Any lightning activity has stayed east of the forecast
area, with only a few small areas of radar returns and light rain
left in parts of southern North Dakota. Ceilings are still modestly
high across much of the area, although some lower cloud decks around
4 to 5k feet have been dropping south from Canada through the early
afternoon. A tight surface pressure gradient has led to strong
northwest winds through the day, gusting around 40 mph in the James
River Valley, closest to the center of the low. Afternoon highs will
be in the mid 40s to lower 50s, with the cloud cover and winds
making it feel even cooler.

Synoptic flow is progged to become somewhat split tonight into
Friday, as a southern stream trough digs over the Southern Rockies,
while the northern stream wave moves south from the Canadian
Prairies into North Dakota. The main change with this forecast
update was to broad brush a 20 percent chance of precipitation,
starting in the north overnight tonight and expanding south through
the day Friday. The last few runs of high-res guidance have been
relatively consistent in bringing in widely scattered showers , in
line with the base of the northern stream trough swinging through
the state. We expect these to be primarily rain showers, although
with cooler temperatures, can`t rule out some snow either mixing in
with the rain or a total transition from rain to snow. Any
accumulations would be very light and limited to grassy surfaces.
Cooler temperatures and breezy northwest winds will accompany the
chances for showers, with highs back into the 40s on Friday.

This weekend looks much more pleasant compared to today and
Friday, as a low amplitude upper ridge moves through the
Northern Plains region. Expect widespread highs back into the
50s on Saturday, and the 60s on Sunday. Southerly winds will be
a bit lighter on Saturday, compared to 15 to 20 mph on Sunday.
Clouds will begin increasing on Sunday ahead of approaching
chances for precipitation.

Ensemble cluster analysis favors broad southwest flow aloft for the
first half of next week, with a trough passing through the Northern
Rockies into the Northern Plains at some point Monday into Tuesday.
Latest NBM output gives a broad 30 to 60 percent chance of
precipitation across the area Monday through Tuesday evening.
Overall p-type is strongly favored to be rain, although can`t rule
out some snow mixing in across the north Tuesday morning. At this
point the probability for any substantial amounts of liquid
precipitation is marginal, with a low chance for exceeding 0.50
inches of rain over any 48 hour period. There could be a few
thunderstorms in the mix as well, with deterministic models
advertising a couple hundred J/kg of CAPE.

There is high confidence in seasonable temperatures next week, with
max temperatures in the 50s and 60s. There are some signs of a brief
cooldown from Monday to Tuesday, although temperatures are still
favored to stay near normal.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1243 PM CDT Thu Apr 17 2025

VFR conditions through most of the period, with a few scattered
showers in the James River Valley to start the 18Z TAF period.
Some low VFR ceilings are moving in across northern North
Dakota, with occasional MVFR cloud decks embedded. Winds will
diminish some overnight as scattered rain/snow showers move
south through the end of the TAF period, although too low of
confidence in timing and location to include at any one site
with this update. MVFR ceilings are also expected to move in
early Friday morning, with northwest winds staying breezy
through the end of the period.

&&

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

&&

$$

DISCUSSION...Jones
AVIATION...Jones