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000
FXUS63 KBIS 211455
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
955 AM CDT Sun Apr 21 2024

.KEY MESSAGES...

- Dry with some breezy areas today, resulting in near critical
  fire weather conditions.

- Rain shower chances late tonight, Monday, lingering through
  Monday night. Greatest chances (~20 to 50 percent mainly
  north of Interstate 94) Monday afternoon and evening.

- West to northwest winds gusting to 50 mph possible Monday,
  with the highest gusts over western and far south central
  North Dakota.

- Critical fire weather conditions possible Monday over much of
  southwest and south central North Dakota. A Fire Weather Watch
  has been issued over these areas.

&&

.UPDATE...
Issued at 955 AM CDT Sun Apr 21 2024

Quiet weather continues this morning. Limited updates needed at
this time. There are some high clouds in Montana making their
way eastward. This could bring some increasing clouds this
afternoon, with limited impacts on the current forecast.

UPDATE
Issued at 639 AM CDT Sun Apr 21 2024

Quiet weather remains over the area this morning, so no changes
needed at this time.

&&

.DISCUSSION...
Issued at 401 AM CDT Sun Apr 21 2024

Current surface analysis places high pressure stretching through
the northern and central plains. Upper level analysis places
ridge over eastern Montana into Saskatchewan, while low pushes
into the Pacific Northwest/British Colombia. Quiet northerly
flow remains over our area with clear skies.

For today, ridge pushes over our area, though starts to break
down later in the day as a lobe of the aforementioned upper low
breaks off and pushes east, starting to close off as it enters
the Canadian prairies. Ahead of this feature, a quiet and mainly
clear day is expected with highs warming to above average.
Southwest winds will be on the increase, becoming a bit breezy
over some areas in the afternoon, as a trough to the lee of the
Rockies deepens and surface high settles southeast.

Tonight, aforementioned upper low deepens some but remains
rather compact as it moves over Saskatchewan nudging into
Manitoba as the surface trough pushes over our area. This may
bring a few light rain showers primarily to southwest and south
central portions of our area, but these will be light at best as
there is quite a bit of dry air to overcome.

Monday will become quite windy over the area as the surface low
shifts over Manitoba, continuing on its way towards Lake
Superior, resulting in a tightening pressure gradient over
western and central North Dakota, tightest towards the west and
south. Forecast soundings continue to show the possibility of
stronger winds mixing down, so will continue to mention the
potential for winds gusting to 50 mph, especially over western
and parts of south central North Dakota. As for precipiation,
upper low continues to trail the surface features a bit, with
cyclonic flow stretching through our area. This will continue
to bring chances for rain showers, mainly along and north of
Interstate 94 (~20 to 50 percent, generally greater as you go
north). With that said, for anywhere that does receive
precipitation chances for much remain low, with NBM showing
about a 20-30 percent chance for seeing a tenth or more.

System departs Tuesday with forecast now looking dry, but breezy
winds will remain into the early morning, gradually decreasing
from northwest to southeast as the day goes on. Upper ridge
passing through the region will bring continued dry conditions
through Wednesday. Guidance then shows the upper flow shifting
southwest and becoming active for the latter part of the work
week into the weekend, resulting in precipitation chances.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 639 AM CDT Sun Apr 21 2024

VFR conditions are expected to prevail through the forecast
period.

&&

.FIRE WEATHER...
Issued at 401 AM CDT Sun Apr 21 2024

Dry conditions are expected across the area today, with afternoon
minimum relative humidity values dipping into the mid teens to
mid 20s. Southwest winds will increase to 15 to 20 mph over most
locations, resulting in near critical fire weather conditions
across all of western and central North Dakota.

On Monday, winds will become west to northwest, increasing to 25
to 35 mph with gusts to 50 mph over much of the area. The lowest
humidity values of 20 to 25 percent are expected to be mainly
along and south of Interstate 94. Given the strong winds and low
humidity values, a Fire Weather Watch has been issued for much of
southwest and south central North Dakota for possible critical
fire weather conditions. Given the latest trends signaling the
possibility for the drier air to stretch further to the east,
would not be surprised if the watch will need to be expanded
east into the James River Valley later today, but again, that
depends on if this trend continues. Near critical fire weather
conditions are expected for most remaining areas with the
possible exception of northwest North Dakota.

There is a 20 to 50 percent chance of rain showers mainly north
of Interstate 94, with highest chances further north, though
some chances do dip through south central North Dakota into the
James River Valley mainly during the morning hours. With that
said, most of these showers are expected to be quite light with
only about a 20 to 30 percent chance of a tenth of an inch or
more, thus the warm/dry wind in the afternoon should dry out
fuels over the south but will have to monitor. A concern at this
point is virga or a very light shower passing through with dry
air down low, which would lead to erratic wind gusts.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
Fire Weather Watch from Monday afternoon through Monday
evening for NDZ031>036-040>047-050.

&&

$$

UPDATE...Anglin
DISCUSSION...JJS
AVIATION...JJS
FIRE WEATHER...JJS