Area Forecast Discussion
Issued by NWS Bismarck, ND

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FXUS63 KBIS 010644

Area Forecast Discussion
National Weather Service Bismarck ND
1244 AM CST Wed Mar 1 2017

Issued at 1242 AM CST Wed Mar 1 2017

Snow continues to quickly track southeast across North Dakota.
Radar indicates snow is not quite as robust as it was earlier.
The latest high-res data also supports this weakening trend.
Therefore...lowered snow amounts across central North Dakota and
the James Valley.

UPDATE Issued at 953 PM CST Tue Feb 28 2017

Made a few changes to pops based on latest radar and mesoscale
models. The latest HRRR/RAP/NAMNest all matched current radar
reasonable well and all had a similar solution in bringing an area
of snow across the north from Williston to Minot, Bottineau and
Rugby and south to Garrison, Harvey and Carrington. With another
smaller area tracking from the southwest through far south central
ND. Bismarck Mandan would be right between these and may see a
little light snow but little or no accumulations. Current models
indicate the favored area for an inch or two would be from around
Minot to Rugby. Maybe as far north as Bottineau and Rolla, and as
far south as Harvey. Snow amounts in the southwest and far south
central are expected to be minimal, maybe a half inch or less.
Updated text products sent shortly.

UPDATE Issued at 620 PM CST Tue Feb 28 2017

Shortwave energy moving through central into eastern Montana with
an associated surface trough situated over southeast Montana and
northeast Wyoming. These will track east across the forecast area
tonight bringing a swath of light snow to the forecast area.
Currently, more convective looking showers were poised to move
into southwest ND. There is some weak cape with strong low and mid
level lapse rates into far southwest ND. However, shear is very
weak and lapse rates lessen quickly as you move east into ND. We
will add a mention of an isolated evening snow shower in the
southwest. Farther north and east across northwest into the north
central light reflectivities were increasing but have not seen any
recent observations with snow yet. Expect snow chances to
increase here this evening. The most likely area for any light
accumulations will be across the north.

For the early evening update we adjusted pops a bit as mentioned
above. Populated latest sensible weather elements and interpolated
to mid evening values. Did adjust the northeast a bit where Rugby
had already dropped to 3 above, which was already lower than the
forecast low. May drop a few more degrees this evening but expect
steady or rising temperatures with increasing clouds and snow
chances later this evening.


.SHORT TERM...(This evening through Wednesday)
Issued at 309 PM CST Tue Feb 28 2017

Current surface analysis places low over central and eastern
Montana with weak ridge over central and eastern North Dakota.
Upper level analysis places weak trough sliding through
central/eastern Montana with some light snow starting to develop.

For the rest of this afternoon into tonight...aforementioned
light snow over Montana will slide over the area from west to
east. Most snow should remain mainly over the northern 2/3rds of
the area with accumulations of possibly an inch or two.

On Wednesday...aforementioned snow will exit the area by mid-day,
though the next short wave will be right behind, pushing into far
western areas in the afternoon, into central areas in the evening.
Again, accumulations of an inch or two are possible, primarily
over central portions of the area.

.LONG TERM...(Thursday through Tuesday) Issued at 309 PM CST Tue
Feb 28 2017

Train of perpetual short waves continue into the area on Thursday,
with another wave sliding through Thursday night into early
Friday bringing snow chances. Changes do come to the area, though,
on Friday as a ridge starts building into the area bringing a
warming in temperatures. This will remain into the weekend, though
locations over north central North Dakota may not warm quite as much
where a denser snowpack remains. A few weak waves move through
during the weekend into early next week bringing an occasional
chance for rain or snow.


.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 1242 AM CST Wed Mar 1 2017

A low pressure system will across the forecast area tonight into
Wednesday morning. This will bring lowering ceilings to MVFR and
occasionally IFR, especially from KISN to KMOT and KJMS. MVFR to
occasional IFR visibilities in light snow are also expected to
impact mainly KISN and KMOT tonight and spreading into KJMS early
Wednesday morning. An occasional MVFR-IFR ceiling/vsby can not be
ruled out at KBIS and KDIK either, but less certainty here. Ceilings
will lift and winds will shift northwest from west to east during
the day Wednesday. Another system will shift winds back easterly
over western ND by late afternoon with MVFR-IFR ceiling and Vsbys in
snow working west to east again late Wednesday afternoon and evening.



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