Area Forecast Discussion
Issued by NWS Bismarck, ND

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FXUS63 KBIS 211343

Area Forecast Discussion
National Weather Service Bismarck ND
843 AM CDT Fri Oct 21 2016

Issued at 837 AM CDT Fri Oct 21 2016

Friday morning, a surface low pressure system across Saskatchewan
and an associated warm front extending south into central North
Dakota was moving east through the state. Scattered showers, some
of which were virga, extended from the Turtle mountains through
south central North Dakota. Current forecast has much of the
showers accounted for but will extend the slight chance for
a shower or two into south central North Dakota for a few hours
this morning. Otherwise current forecast looks good.

UPDATE Issued at 617 AM CDT Fri Oct 21 2016

Made some changes to pops to account for the line of showers
moving from northwest into north central ND. Otherwise no changes
other than updating latest sensible weather grids.


.SHORT TERM...(Today and tonight)
Issued at 303 AM CDT Fri Oct 21 2016

A shortwave trough will move east along the International Border
today, with an associated surface trough and weak cold front
moving across the forecast area.

Currently, warm advection isolated showers are moving into
northwest ND. Latest iterations of short term models show this
precipitation remaining mainly along the northern tier counties
this morning. Utilized a blend of short term models for forecast
pops this morning. Showers are expected to exit eastern portions
of central ND around midday. We should warm up nicely today with
highs in the upper 50s to mid 60s. The weak cold front moves into
the northwest late morning/early afternoon and tracks southeast
through the forecast area during the afternoon hours. Expect
increasing west to northwest winds associated with the cold front
but moreso due to the boundary layer mixing out to higher winds
aloft during max heating this afternoon. This will result in
breezy to windy conditions this afternoon across most of western
and central ND.

Winds subside quickly late this afternoon as surface high pressure
quickly builds over the area, and tracks east across the forecast
area tonight. Thus dry tonight with a light westerly flow this
evening becoming southerly over western ND late tonight ahead of
another quick moving shortwave.

Very few changes from given guidance. We did bump up highs a
couple degrees across the forecast area today and also raised
winds a little this afternoon.

.LONG TERM...(Saturday through Thursday)
Issued at 303 AM CDT Fri Oct 21 2016

Another shortwave tracks along the International Border Saturday
afternoon through Saturday night. This one is a little more
interesting as there are some deterministic model differences in
the position of the surface low and strength of the mid level

Southerly flow early Saturday with some warm advection showers
moving along the northern tier counties during the day. The cold
front moves into western ND Saturday afternoon. The NAM/EC are
farther north with the surface low and overall, stronger with the
mid level wave. This would result in warmer daytime highs and
stronger winds Saturday night across western and central ND. A
GFS/Canadian solution would still bring in strong winds across the
southwest Saturday afternoon, but would keep windier conditions
across the far southern tier counties and mainly over South Dakota
Saturday night. We have increased winds above guidance over the
forecast area Saturday and Saturday night. If models continue to
trend to a NAM/EC solution we will likely need to bump up winds
a little more Saturday night.

Cooler Sunday behind the exiting low but dry as surface high
pressure builds over the area. Upper level ridging ahead of an
eastern Pacific trough should provide mild and mainly dry
conditions early next week. The ridge begins to break down by mid
week and several waves may impact the region, bringing chances
for precipitation back into the forecast.


.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
Issued at 617 AM CDT Fri Oct 21 2016

Low pressure over southern Saskatchewan this morning
will move east into Manitoba this afternoon. A cold front
extending south from the low is expected to sweep eastward across ND
today...entering western ND around 15-17z and reaching the James
River Valley by around 20-22z. South winds ahead of the front
becoming west at 15-20 knots with gusts to 25-30 knots.

Areas of MVFR and IFR cigs remain over the James River Valley
this morning with some MVFR fog possible through around 13-15z.
Otherwise...VFR conditions are expected.




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