820
FXUS63 KBIS 150755
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
255 AM CDT Mon Jul 15 2024

.KEY MESSAGES...

- Isolated strong to severe storms remain possible early this
  morning, mainly in and around the James River Valley. Hail to
  the size of golf balls and wind gusts to 60 mph are the main
  threats.

- Expect low to medium chances (20 to 40 percent) of showers and
  perhaps a few thunderstorms tonight through Tuesday, mainly
  across the west and south central.

- Cooler weather returns through midweek with a modest warmup
  expected for the end of the week and into the weekend.

&&

.DISCUSSION...
Issued at 247 AM CDT Mon Jul 15 2024

Western and central North Dakota continues to sit under the
influence of broad upper level troughing. A surface low is currently
located over south central North Dakota with an effective warm front
extending east southeast down into the James River Valley. This
boundary can be seen on radar, clearly associated with the arc of
thunderstorms extending from southeast Sheridan county, over towards
western Foster county, and down to near Jamestown. SPC mesoanalysis
still suggests that 1500 to 2000 J/kg of MUCAPE and effective shear
upwards of 60 knots remains in place where convection is ongoing.
Thus, while the severe threat is slowing down, a few strong to
severe storms will remain possible until this arc of convection
moves out later this morning. Hail to the size of golf balls
and wind gusts to 60 mph will be the main threats. Most of the
CAMs have this activity finally moving out around 09z or 10z
which seems reasonable. Severe Thunderstorm Watch 536 remains in
effect for Foster, Stutsman, Emmons, Logan, McIntosh, LaMoure,
and Dickey counties.

Today will be cooler in the wake of the low and frontal system.
Highs will range from the lower 70s in the vicinity of the Turtle
Mountains, to the mid 80s southwest. Clouds will be decreasing
through the day but increasing again across the north tonight. Highs
will be very similar to today on Tuesday and Wednesday as the upper
ridge to our west amplifies and we remain on the eastern slope in
northwest flow aloft. The ridge starts to nudge towards us through
the end of the week, promoting warming temperatures starting on
Thursday with highs rising back into the lower 80s to lower 90s
through the weekend.

Regarding precipitation chances, a subtle wave will move down the
ridge and bring the next low to medium chances (20 to 40 percent) of
precipitation to the west and south central tonight and into
Tuesday. We could see a few thunderstorms early with this activity
but it should transition to mainly showers fairly quickly given
meager instability. After this wave moves through we should
generally be dry for the rest of the work week. The one exception
could be on Friday when another wave may flatten the ridge briefly,
bringing with it some low chances (20 percent) of showers and
thunderstorms.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1244 AM CDT Mon Jul 15 2024

Thunderstorms continue across parts of central and eastern North
Dakota, most likely to impact KJMS through the next few hours.
Beyond that, a few isolated showers are possible across western
North Dakota, but low confidence in timing and location. Through
the day Monday, winds will generally be from the north-northwest
at 10 to 15 knots.

&&

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

&&

$$

DISCUSSION...ZH
AVIATION...Jones