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fxus63 kabr 121740 aac 

Area forecast discussion...updated
National Weather Service Aberdeen South Dakota
1140 am CST Thu Dec 12 2019

issued at 1137 am CST Thu Dec 12 2019

See below for an aviation forecast discussion for the 18z tafs.

Update issued at 943 am CST Thu Dec 12 2019

For the rest of the day, the forecast is predominantly dry. Can't
rule out a rogue snow flurry/shower as the anticipated low level
waa pattern for later this afternoon into Friday morning begins
to gather strength. Little in the way of forecast high temperature
change is expected for the rest of the day.

Update issued at 524 am CST Thu Dec 12 2019

See updated aviation discussion below.


Short term...(today through Friday afternoon)
issued at 406 am CST Thu Dec 12 2019

Generally low-impact weather through the period, but there are a few
worthwhile notes. 1.) Light snow continues across portions of the
northern and northeastern County Warning Area this morning as a shortwave tracks
across the northern plains. Extensive cloud cover exists elsewhere,
and this cloud cover should largely persist through much of the day.
2.) Next chance for precipitation arrives tonight into Friday
morning, as the next shortwave tracks through. Light warm air advection-induced
snow, moving from west to east, appears most likely. Model soundings
show a lack of ice aloft Friday afternoon, so if we can get a deep
enough near-surface saturated layer around the Coteau, occasional
freezing drizzle may occur. 3.) An Arctic front sweeps through the
area Friday afternoon and early evening. With it comes strong cold air advection
with steepening lapse rates and gusty northwest winds, along with
perhaps some additional light snow (freezing drizzle potential GOES
away with the frontal passage). Considering how cold it's been (no
crusting of the latest rounds of light snow), at least a bit of
drifting of snow across roadways seems probable.

Temperatures will stay below average generally along and east of the
Missouri River today, but a moderating trend will ramp up ahead of
the next system Friday. Friday's highs should be at least in the 20s
across the board, with 30s possible across much of central South
Dakota. Again, the Arctic front will put an end to this brief warm-
up by the early evening.

Long term...(friday evening through wednesday)
issued at 406 am CST Thu Dec 12 2019

Long term period opens with a cold frontal passage, cold advection
and gusty winds, maybe some light snow evident in the low level
thermal profiles. Cold air will persist across the region through
the weekend with some hints at moderation early next week with the
potential for another shot at Arctic air for the middle of the work
week. There are hints that this next blast will be more of a
glancing blow, and warm air could return relatively quickly, albeit
briefly, as we slide back and forth between the Arctic front. Other
then airmass changes, the extended is mostly dry.


Aviation...(for the 18z tafs through 18z Friday afternoon)
issued at 1137 am CST Thu Dec 12 2019

If kpir doesn't get out from underneath the MVFR ceilings sprawled
out across the region, all four terminals will likely remain in
some form of MVFR/lower end VFR cig until later tonight when
cigs are expected to fall below 1000ft agl into the IFR category.
There is a clipper low working through the region later tonight
and Friday, which will slightly increase light snow/freezing
drizzle potential from late tonight through Friday afternoon.


Abr watches/warnings/advisories...
South Dakota...none.


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