776
FXUS63 KBIS 070017
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
717 PM CDT Sat Jul 6 2024

.KEY MESSAGES...

- Scattered showers and thunderstorms (30 to 60 percent) will
  continue through the day across much of western and central
  North Dakota. This activity will be hit or miss.

- Another round of scattered showers and storms (30 to 60
  percent) is expected on Sunday, with the best chances east.
  Some lingering showers and storms will remain possible across
  the east Monday and Tuesday afternoon.

- A gradual warming and drying trend is still expected for next
  week, with temperatures above normal by the end of the week.

&&

.UPDATE...
Issued at 709 PM CDT Sat Jul 6 2024

Upper low over southeast North Dakota has lead to broad cyclonic
flow aloft and thus multiple showers and thunderstorms, and
along with that many funnel clouds. One did touch down to the
south of Stanley in Mountrail County causing some damage to a
farmstead (see respective Local Storm Report for more
information). The threat for funnels continues into early this
evening as the SPC mesoanalysis continues to show elevated
values in the non-supercell tornado parameter (up to 4) over
central and parts of western North Dakota. A Special Weather
Statement remains in effect through mid-evening concerning this.
With that all said, funnel reports have really tapered off over
the past hour or so. Expect activity to greatly taper off later
this evening with the loss of daytime heating, but a few stray
showers/storms may linger for a bit longer.

&&

.DISCUSSION...
Issued at 211 PM CDT Sat Jul 6 2024

Western and central North Dakota sits under the base of an upper
level trough with an upper low located near the South Dakota
border. Most of the showers and storms are currently located
under and around the center of the low over the south central
and into the James River Valley. That being said, storm coverage
and chances (30 to 60 percent) should increase across all of
western and central North Dakota over the next few hours as
diurnal heating really ramps up. In fact, we are already
starting to see one other cluster of storms approaching the
northwest out of northeast Montana.

The environment today remains very similar to the environment
the past couple of days with very little shear and MLCAPE
ranging from 500 to 1500 J/kg. Also similar to previous days, we
have strong low level instability and surface vorticity in
place which could lead to some more weak funnels and/or
landspouts given the very low shear. SPC mesoanalysis lends
further confidence to this threat given non-supercell parameter
values as high as 3. We have had one report of a funnel cloud
near Carrington already this afternoon. Slow storm motions could
also lead to locally heavy rainfall and small hail. Showers and
storms will start to diminish near and after sunset with the
loss of diurnal heating. Highs today will once again be in the
70s with lows tonight in the 50s.

We will see one more day of this pattern on Sunday with another
round of hit or miss showers and storms developing in the
afternoon. However, the chances (30 to 60 percent) will nudge a
bit more to the east. The severe weather threat remains low but
we may see one more day of weak funnel potential. However,
surface vorticity may not be quite as high with the upper low
kicking out into Minnesota. Highs on Sunday will be very similar
to today but maybe just a touch warmer with some lower 80s
possible north central and east.

An expansive western US ridge will start to finally nudge into
the region to start the week. However, our eastern areas
(Devil`s Lake Basin and James River Valley) have the potential
to see some lingering showers and storms in the afternoon Monday
and potentially Tuesday. For the most part, we will see a
drying and warming trend through the week as the ridge moves in
and deamplifies. On Monday, forecast highs will range from the
mid 70s to mid 80s and then by Wednesday we should see highs in
the 80s across all of western and central North Dakota. By
Thursday and Friday, we will see widespread highs in the upper
80s to mid 90s.

&&

.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 709 PM CDT Sat Jul 6 2024

Isolated to scattered showers and thunderstorms will continue
to affect most TAF sites through mid-evening, with activity
diminishing later this evening. Showers and storms may return
again late morning into mid-day Sunday, continuing through
Sunday afternoon for most locations, with the possible exception
being far western North Dakota.

&&

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

&&

$$

UPDATE...JJS
DISCUSSION...ZH
AVIATION...JJS