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000
FXUS63 KBIS 130949
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
449 AM CDT Sun Aug 13 2017

.SHORT TERM...(Today and tonight)
Issued at 430 AM CDT Sun Aug 13 2017

H5 low remains over the forecast area as it was pushing just very
slowly east as of this writing. Two significant short waves were
rotating in the closed flow with one continuing the rain south of
Bismarck and the other resulting in an expansion and
intensification of rain through the James River Valley.

Low clouds and fog will be slow to burn off this morning with
erosion coming from the northwest as sunshine there works to
evaporate the northern periphery.

The low moves into Minnesota this evening ending the rain east.

Weak H5 ridging moves in for a mainly clear sky tonight, but with
high low level moisture in place fog will likely result,
especially across the south.

.LONG TERM...(Monday through Saturday)
Issued at 430 AM CDT Sun Aug 13 2017

As the weak H5 ridge passes Monday southwest flow aloft becomes
established, and with increasingly diffluent flow, upward motion
results. This is aided by the nose (left front) of an H2 jet.
Surface support is also present in the form of, by Monday
afternoon, a surface boundary advancing to the Montana and North
Dakota border with convergence, lifting, and moisture pooling.
This results in thunderstorm development. With lapse rates
steepening and shear profiles increasing, strong to near severe
storms could be possible along and west of highway 85 by mid to
late afternoon.

This long wave trough advances with a parade of short waves
keeping the chance for storms going right through Monday night
and into Tuesday. With that comes a lot of clouds and temperatures
only in the 70s for most places.

Beyond that, less organized systems and triggers for the end of
the week should spell more hit or miss showers and storms rather
than the widespread ones of late. With that is more solar
insolation and the expectation that lower 80s for highs will be
more common.

&&

.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 430 AM CDT Sun Aug 13 2017

Areas of IFR ceilings and visibilities in FG have formed in the
moist low levels while showers and some thunderstorms continued
from the KBIS area through the KJMS area as of this writing. Low
clouds and fog will be slow to burn off this morning with showers
and storms possible through the day in the KJMS area.

By way of planning, fog looks possible to likely again late Sunday
night into monday morning.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...JPM
LONG TERM...JPM
AVIATION...JPM