386
FXUS63 KBIS 070931
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
431 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.

&&

.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 /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 117 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/visibility: Most terminals should see a break in
persistent rainfall overnight. During the day Tuesday, rain should
fill back in across western and northern North Dakota, with more
isolated to scattered shower activity across south central and
southeast North Dakota. A few flashes of lightning cannot be
completely ruled out, but the probability for TS is very low.
Visibility could be reduced to MVFR/IFR levels in heavier showers.

Ceilings: Parts of southern North Dakota will see some breaks in low
ceilings overnight, and this trend may continue at KJMS into Tuesday
morning. Otherwise, the overall expectation is for MVFR/IFR ceilings
to prevail.

Wind: Central North Dakota will continue to see strong east-
southeast winds overnight into Tuesday morning, with a gradual
decrease in intensity Tuesday afternoon and evening. Northwest North
Dakota will have easterly winds around 10 kts overnight, turning
slight to the northeast and increasing to around 15 kts with gusts
to 25 kts Tuesday afternoon. For most of southwest North Dakota,
expect easterly winds around 10 kts overnight, gradually turning to
the north and then west during the day Tuesday. The far southwest
corner of the state, primarily Bowman County, will see much stronger
westerly winds on Tuesday, with sustained speeds up to 50 kts and
gusts to 45 kts.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
Wind Advisory from 9 AM this morning to 8 PM MDT this evening
for NDZ043-044.

&&

$$

DISCUSSION...Hollan
AVIATION...Hollan