Area Forecast Discussion
Issued by NWS Bismarck, ND

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FXUS63 KBIS 200638

Area Forecast Discussion
National Weather Service Bismarck ND
138 AM CDT Mon Mar 20 2017


Issued at 136 AM CDT Mon Mar 20 2017

Upper level jet dynamics (mentioned in the previous discussion)
continues to result in a decent area of light to moderate
precipitation southwest into parts of my south central. We
increased POPs for these areas based on regional radar and near
term high res guidance. Still think it will be hard to accumulate
any snow if and when we change over to snow with warm surface and
ground temperatures. Will monitor closely overnight.

UPDATE Issued at 950 PM CDT Sun Mar 19 2017

Main forecast problem this evening is placement of precipitation.

Latest satellite and radar imagery show a jet induced band of
showers mainly along the I-94 corridor. Much of the precipitation
is reaching the ground but again late this evening Bismark Mandan
received another shower. However so far, amounts are only trace.
Another potent jetlet is expected to develop over the northern
High Plains and propagate rapidly into the western Dakotas late
tonight. The 20 March 00UTC NAM is showing the resulting
precipitation farther north than previously forecast. The latest
mesoscale models are still holding onto a farther south track and
currently do not line up that well with the current shower
activity. The result may not end up to mean a whole lot, but the
NAM is producing a stronger qpf reflection, along the interstate
in west central ND. This is currently farther north than where we
have our highest pops. SPC page is showing some strong fg forcing
over western ND and the NAM may be picking up a a bit of coupling
between the strong aforementioned jetlet and the strong jet that
is currently situated over northern ND. With nothing other than
the NAM to indicate this farther shift northward, we will pull our
higher pops a little farther north, closer to the NAM,but keep the
higher pops in the south for now, as there are some reflectivities
developing over northwest SD at this time. IF the NAM is right and
subsequent runs of the mesoscale models pick up on this, the
overnight shift can adjust accordingly. With the strong qpf signal
by the NAM, higher snow amounts may be needed. With the warm
temperatures, currently in the mid 40s, snow amounts still look on
the light side, but an area of an inch or two in grassy areas can
not be discounted.

UPDATE Issued at 639 PM CDT Sun Mar 19 2017

Strong upper level jet is producing a band of showers extending
west to east along and south of the I-94 corridor in southern
North Dakota. Most of this activity is not reaching the ground
but there have been a few sprinkles reported with the stronger
reflectivities, including a trace at both Dickinson and Bismarck.

For the update we adjusted pops slightly farther south and east
with some higher reflectivities from south of Bismarck into the
southern James River Valley. Another impulse is expected to bring
increasing precipitation chances again later tonight to the
southwest and far south central, with a better chance of some
light rain/snow accumulations over the far southwest and south


.SHORT TERM...(This evening through Monday)
Issued at 314 PM CDT Sun Mar 19 2017

Light rain across southern North Dakota will likely transition to
light snow later this evening as temperatures fall. Little to no
accumulation is expected. Precipitation will come to an end from
northeast to southwest overnight tonight.

High pressure will seep into North Dakota tonight and with a shift
to a northerly wind Monday will be cooler with temperatures in
the 30s and 40s.

.LONG TERM...(Monday night through Sunday)
Issued at 314 PM CDT Sun Mar 19 2017

The next chance for precipitation arrives Wednesday as a weak wave
moves through and we shift to southwest flow aloft. A mix of rain
and snow is expected with no accumulating snowfall.

Temperatures this week will generally range from the 30s north to
40s south.

Models still depict a major storm later this week, but latest
trends keep it south of North Dakota.


.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 133 AM CDT Mon Mar 20 2017

Gusty winds to 40kt at KMOT and KJMS will diminish to around 30kt by
15z Wednesday. Mvfr cigs at KMOT and KJMS are also expected to
improve to vfr by around 15z Wednesday. Otherwise vfr conditions at
the remaining terminals. The next round of mvfr cigs/vsbys in -sn
begin at KISN around 03z Thursday. MVFR cigs forecast at KDIK and
KMOT by 06z Thursday and KBIS around 10Z Thursday.


Issued at 950 PM CDT Sun Mar 19 2017

Little Muddy River north of Williston was rising quickly and was
at around 9.5 feet at 3 PM this afternoon. After coord with RFC we
issued a flood warning taking the river to just above flood stage
later tonight and dropping below late Monday morning. Since then
the stage has fluctuated between 9 and 9.5 feet. The river remains
iced over and rapid fluctuations due to ice action are possible.
Will continue the warning through the night due to the level
being so near flood stage and with ice jams possible.




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