FXUS63 KBIS 152220

Area Forecast Discussion
National Weather Service Bismarck ND
520 PM CDT Sat Jun 15 2019

Issued at 503 PM CDT Sat Jun 15 2019

Convection was ongoing late this afternoon from the James River
Valley region of North Dakota through the western Missouri River
valley area of Williams and McKenzie counties. A surface boundary
was placed from the Turtle Mountains south through Dickey county.
Even with weak midlevel flow and effective shear values, thunderstorms
on this boundary have taken advantage of enhanced surface
vorticity as well as a relatively more moist boundary layer to
produce several reports of funnel clouds and at least one tornado.
Further northwest, lower surface dew points and weaker surface
convergence have limited the tornadic potential in that area. The
marginal severe threat continues for storms in the LaMoure/Dickey
area where effective bulk shear is closer to 30 kts.

Expecting this convection to continue for the most part through
the evening with coverage and intensity diminishing with the loss
of diurnal heating.


.SHORT TERM...(This evening through Sunday)
Issued at 235 PM CDT Sat Jun 15 2019

This afternoon, an inverted surface trough axis was analyzed from
around the Turtle Mountain region south through the James River
valley. Convective activity aided by convergence along this zone
was ongoing this afternoon in an environment marked by 500-1500
J/kg of MLCAPE and less than 20 kts of bulk through much of
western and central ND. Effective bulk shear increases to around
30 kts in the southern James River valley, which will be an area
of possibly stronger thunderstorms through this evening. Though
classic severe weather ingredients are meager, an isolated chance
of a weak tornado risk does exist along the strong surface
boundary wind shift and instability corridor this afternoon and
early evening.

This evening, the surface trough axis moves into eastern North
Dakota and the scattered showers/thunderstorms behind it slowly
diminish with the loss of daytime heating. Isolated showers
overnight will still be possible, especially in the northern
counties with a weak closed upper low deepening over southern

On Sunday, chances for isolated showers in the afternoon with the
upper low center moving over northern North Dakota and weak DCVA
placed over the state. Kept most mention of thunderstorms out of
the forecast with surface dew points in the 40s. Temperatures
remain seasonably cool with highs in the 60s north to low 70s

.LONG TERM...(Sunday night through Saturday)
Issued at 235 PM CDT Sat Jun 15 2019

Sunday night through mid-week, the upper low developing over
southern Canada today will slowly move over the northern plains
through the upper midwest...keeping North Dakota in a seasonably
cool pattern. Cold air aloft will bring almost daily chances for
showers and thunderstorms, with severe weather not expected in the
colder pattern.

The 12Z global models continue the trend of bringing in a midlevel
jet stream over the northwest CONUS by the end of next week,
though with considerable difference in how it develops the flow
pattern over the northern plains. Continued chances for
precipitation will be expected through the end of the week with
uncertainty in timing as well as thunderstorm chances.


.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1221 PM CDT Sat Jun 15 2019

Widespread showers and thunderstorms will develop across much of
western and central North Dakota this afternoon. MVFR ceilings
will also spread across central and eastern North Dakota this
afternoon and tonight. Generally VFR west.




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