941
FXUS63 KBIS 071208
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
708 AM CDT Tue May 7 2024

.KEY MESSAGES...

- Widespread showers are expected across western and northern
  North Dakota today, with isolated to scattered showers south
  central into the James River Valley.

- Strong westerly winds are expected along and south of Highway
  12 in far southwest North Dakota from mid morning to early
  evening today.

- A transition to warmer and drier weather is expected for the
  end of the work week and into the weekend.

&&

.UPDATE...
Issued at 707 AM CDT Tue May 7 2024

At 700 AM CDT, the center of the surface was located over western
parts of the Standing Rock Reservation. Patchy fog has developed to
the north and west of the low in southwest North Dakota where an
inverted trough is maintaining lighter winds. The fog should lift by
mid morning as low clouds fill back in and winds increase.
Otherwise, the forecast for today remains on track.


&&

.DISCUSSION...
Issued at 430 AM CDT Tue May 7 2024

A stacked low pressure system with MSLP down to 983 mb is spinning
over northwest South Dakota early this morning. The mid/upper trough
that the low resides in exhibits negative tilt, placing the warm/
moist conveyer belt with a continuous stream of cyclonic vorticity
advection from southern Minnesota curling toward southeast
Saskatchewan, the deformation zone with strong upper level
divergence over eastern Montana, and a dry slot from southeast and
central South Dakota into south central and southwest North Dakota.
The low is forecast to slowly drift northeastward into south central
North Dakota throughout the day while becoming elongated in a west
to east fashion. High-resolution and global ensembles are well-
aligned with high chances for rain across northern and western North
Dakota this morning and afternoon, with more isolated to scattered
shower activity expected south central to southeast. A strong band
of low level westerly winds wrapping around the low will clip the
far southwest corner of the state today, which is expected to bring
advisory criteria winds and gusts to areas along and south of
Highway 12. A Wind Advisory has been issued for Bowman and Adams
Counties from mid morning to early evening. High temperatures today
are mostly expected to be in the 50s, but will likely be limited to
the mid to upper 40s in the southwest.

The stacked low is forecast to gradually weaken and drift southward
later tonight through Wednesday. High chances for lighter rain
remain in the forecast for southwest North Dakota through Wednesday
afternoon, where some guidance maintains a pocket of enhanced Q-
vector convergence. The rest of the state will still see low to
medium chances for rain through Wednesday with the continued
presence of mid level cyclonic vorticity. There could be some peeks
of sun on Wednesday, but it will likely be another mostly cloudy day
with slightly warmer high temperatures in the mid 50s to mid 60s.

The NBM shows low chances for rain departing all but southwest North
Dakota by Thursday morning as a northeast-pointing upper ridge
brings anticyclonic flow over the region. This should result in
greater sunshine and temperatures finally warming into the mid and
upper 60s. A clipper-like system is then forecast to dig into the
Upper Mississippi River Valley and western Great Lakes region on
Friday. Most of the forcing will lie east of our forecast area, but
central North Dakota could see isolated to scattered afternoon
showers under the cyclonic northwest flow. Despite the passage of
the cold front attendant to the clipper, highs are still expected to
reach the mid to upper 60s again on Friday. But as is the case with
clippers, a breezy, if not windy day can be expected.

Mean ensemble height fields suggest a northwest flow pattern over
the Northern Plains this weekend into early next week, with a
potential for one or two shortwave passages. Despite this, there is
medium to high confidence in temperatures rising above normal for
most areas over this time period, with upper 60s to mid 70s for
highs and 40s for lows. The NBM maintains a dry forecast for the
weekend, with only low chances for showers and thunderstorms
returning on Monday.

&&

.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 707 AM CDT Tue May 7 2024

A low pressure center will continue to spin over western and central
North Dakota through the forecast period.

Precipitation: Widespread showers are expected to develop across
western and northern North Dakota this morning and afternoon, with
more isolated to scattered shower activity across south central and
southeast North Dakota in the afternoon. A few isolated
thunderstorms could also develop across portions of central North
Dakota this afternoon.

Visibility: Patchy dense fog is possible at KDIK this morning. MVFR
to IFR reductions are possible in heavier showers.

Ceilings: Parts of south central North Dakota will see VFR
conditions early this morning. Otherwise, the overall expectation is
for MVFR/IFR ceilings to prevail through the afternoon. Areas from
KJMS to KBIS could see an improvement to VFR ceilings this evening,
with lower ceilings continuing elsewhere.

Wind: Northern and eastern North Dakota will see easterly to
southeasterly winds around 15 kts today. South central and far
southwest North Dakota should experience lighter and variable winds
today due to the proximity of the center of the low. The far
southwest corner of the state, primarily Bowman County to KHEI, will
see much stronger westerly winds today, with sustained speeds up to
30 kts and gusts to 45 kts.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
Wind Advisory until 8 PM MDT this evening for NDZ043-044.

&&

$$

UPDATE...Hollan
DISCUSSION...Hollan
AVIATION...Hollan