Area Forecast Discussion
Issued by NWS Bismarck, ND

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FXUS63 KBIS 230843

Area Forecast Discussion
National Weather Service Bismarck ND
343 AM CDT Fri Mar 23 2018

.SHORT TERM...(Today and tonight)
Issued at 340 AM CDT Fri Mar 23 2018

Heavy snow and near whiteout conditions across most of western and
central North Dakota highlight the short term forecast. No changes
to ongoing winter headlines at this time.

As of 840 UTC, a band of moderate to heavy precipitation was
observed from Beach through Mott and Hettinger on the ND ARB
Bowman radar. This band will continue to spread northeast early
this morning reaching Williston and Bismarck around 11-12 UTC,
Minot around 14-15 UTC, and Jamestown around 15-16 UTC based on
the RAP/HRRR trends through their 07 UTC iterations which have
performed well thus far.

Outside of the far southwest, snow is the favored precipitation
type with strong dynamic cooling. Heavy snowfall rates are
expected as strong low to mid level frontogenesis couples with
deeper large scale forcing, yielding strong omega in the
dendritic growth zone. One source of uncertainty regarding
snowfall accumulations is compaction relating to near freezing
temperatures, which in themselves are still a bit uncertain for
today, and strong southeast winds. Still, widespread 6 to 10
inches of snow, with isolated 12 inch amounts, are favored across
most of northwest and central North Dakota. Accumulations drop off
to around 3 to 6 inches from Watford City through Dickinson, Fort
Yates and Linton, with minimal accumulations far southwest where
mostly rain is expected. Regarding winds, near white-out
conditions are expected from heavy snow rates and 40-45kts at the
top of a shallow mixed layer at around 880mb potentially
transferring to the surface.

A relative lull in precipitation is possible late this morning and
into the early afternoon south central, until precipitation may
once again fill in later this afternoon into the evening with the
arrival of a stronger shortwave. After this morning, little
additional precipitation may fall across the far southwest.
Precipitation is expected to decrease from west to east this
evening and into the early overnight. Patchy freezing drizzle is
possible with ice loss in the column tonight.

Again, surface temperatures will be critical to precipitation type
and snowfall accumulations, and this remains a primary source of
uncertainty even at this time. Even a one or two degree
difference in air temperature will have big impacts. A second
source of uncertainty is compaction from the warm temperatures
and wind.

.LONG TERM...(Saturday through Thursday)
Issued at 340 AM CDT Fri Mar 23 2018

An active weather pattern continues to highlight the extended

The 00 UTC global suite continues to favor active southwest flow
aloft across the Northern Plains Saturday into early next week.
Two main systems are forecast, one potentially Saturday night into
Sunday, and a second stronger system for Monday. While
accumulating snow is possible, near to above freezing air
temperatures may likely yield a rain and snow mix.


.AVIATION...(For the 06Z TAFS through 06Z Friday night)
Issued at 340 AM CDT Fri Mar 23 2018

Widespread LIFR/VLIFR conditions in heavy snow developing across
southwest North Dakota spreading into northwest and central North
Dakota Friday morning. The band of heavy snow is expected to
arrive at KDIK around 09 UTC, KISN/KBIS around 11-12 UTC, KMOT
around 14-15 UTC, and KJMS around 15-16 UTC. Fog is likely to
precede precipitation for most areas. Strong southeast winds with
gusts of 30-40 kts are expected to accompany the snow. A rain and
snow mix is possible through the event across the far southwest,
southwest of KDIK. Precipitation will decrease from west to east
Friday evening and night. Patchy freezing drizzle is possible
Friday night into Saturday morning.


Winter Storm Warning until 7 AM CDT /6 AM MDT/ Saturday for

Winter Weather Advisory until 1 AM CDT /midnight MDT/ Saturday
for NDZ017-032-033-041-042-045-046.

Winter Storm Warning from 7 AM this morning to 7 AM CDT Saturday
for NDZ001>005-011>013-022-023-025-036-037-047-048-050-051.



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