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Area forecast discussion 
National Weather Service Bismarck ND
1248 PM CST Friday Nov 28 2014

Update...
issued at 1247 PM CST Friday Nov 28 2014

No significant changes with the update. Radar continues to show
diminishing reflectivities...with a few surface observation continuing to
indicate some locations still picking up some light snow. Models
had hinted at some precipitation possible across the southwest this
afternoon and although kbis 88d and Bowman radar show some
increase in reflectivities...ceilings remain relatively high and
stronger returns are just southwest of our are. Therefore...kept
probability of precipitation out of the southwest and maintained low chances...mainly
north.

Update issued at 925 am CST Friday Nov 28 2014

Continued trend of decreasing probability of precipitation. Radar/surface observation continue to
indicate mainly light snow occurring at several locations north central
through eastern ND. Back edge of scattered stronger reflectivities
continue to move eastward...although several Canadian surface observation
just north of border...including cyen...continue to show light
snow. Therefore...maintained low probability of precipitation closest to Canadian border
through the day. Any light precipitation across the northwest would
likely be in form of freezing drizzle as warm air convection aloft
continues during the day with surface temperatures remaining below
freezing.

Update issued at 700 am CST Friday Nov 28 2014

Updated to decrease probability of precipitation further...however...could not completely
remove them most areas as Doppler radars continue to show pockets
of precipitation upstream. Vertical atmospheric profile and
surface observations continue to show light freezing rain as the
main hazard this morning.

&&

Short term...(today and tonight)

Issued at 400 am CST Friday Nov 28 2014

Forecast highlights in the short term period will be freezing
precipitation this morning and a continued chance of a wintry mix
today into tonight.

Currently...broad ridging across the western half of the United
States. Frontal boundary stretched from northern Montana southeast
through southwestern North Dakota into southern Minnesota.
Embedded middle level wave moving east-southeast across North Dakota
at the moment...interacting with the boundary to result in an
area of precipitation moving with the wave east-southeast from
western into south central ND. Warm/above freezing air aloft
coupled with well below surface temperatures resulting in a swath
of freezing rain/sleet from Williston to Dickinson...east to
Garrison and Bismarck. We opted to go with a Special Weather
Statement due to the relatively short duration of the freezing
rain...roughly 2-3 hours...and amounts much less than a tenth of
an inch. Should see this area of freezing rain/sleet/mix exit off
to our south and east by 15z with the embedded shortwave.

Will allow the Winter Weather Advisory to expire with this
forecast package. Light snow continues across the far north...but
only light amounts are anymore expected with minimal impacts.

Warm front pushes east across the state this afternoon and evening
as surface low pressure advances into western North Dakota. This
will allow temperatures to rebound 10-20 degrees compared to
Thanksgiving day. Already 37f at Bowman! Cold front then starts
to move south after 06z behind the departing low.

With warm air aloft advancing north and east across the County Warning Area
today into this evening...any precipitation chances will see a
threat for freezing rain over those areas where the surface
temperatures remain at or below freezing. This will hold true for
late tonight as well. We should be dry for this afternoon and
tonight south...with the more favorable areas for light snow or a
mix across the north.

Long term...(saturday through thursday)
issued at 400 am CST Friday Nov 28 2014

The long term starts with high chances for light precipitation in
the form of snow north and freezing rain south. This as a surface
low and strong warm air advection cross North Dakota Saturday
morning. By afternoon the low is in northern Minnesota with strong
cold air advection following. Vertical temperature profiles would
favor a carryover of freezing rain Saturday...from Friday
night...changing to snow Saturday afternoon. Although chances of
precipitation look high...amounts look low...on the order of a few
hundredths at most. Will need to monitor for possible advisory if
later guidance suggests more than that few hundredths. At this
point...with a Special Weather Statement ongoing for pockets of
freezing rain occurring early this Friday morning...will not
confuse the issue with one for Saturday.

Much colder air Ushers in for the rest of the weekend and through
the early part of next week...with nothing more than flurries from
time to time. By late week moderation in temperature should be
expected as the center of the cold pool over hudsons Bay slides
southeast allowing more zonal flow into the Dakotas.

&&

Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 1247 PM CST Friday Nov 28 2014

Continue to see MVFR to IFR conditions across the north and east including
kisn...kmot and kjms which are expected to continue through the
period. Ceilings have lifted across southern locations with VFR
conditions at kdik and kbis. A strong cold front will push
southward overnight resulting in deteriorating conditions and
another chance for light snow and freezing rain. Any freezing rain
should be of short duration with a rapid changeover to snow.

&&

Bis watches/warnings/advisories...
none.
&&

$$

Update...jns
short term...New Hampshire
long term...jpm
aviation...jns

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