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Area forecast discussion for western South Dakota and northeastern Wyoming 
National Weather Service Rapid City South Dakota
237 am MST Wednesday Feb 10 2016

Short through Thursday night
issued at 234 am MST Wednesday Feb 10 2016

Northwest upper flow continues over the central states...with
upper ridge persisting over the west. Band of stratus has pushed
into eastern South Dakota...leaving the County Warning Area mostly clear. Surface
low/stationary boundary stretches across the central Dakotas.
Winds are light and generally westerly...and temperatures are mostly in
the 20s to low 30s. Some 40s and even lower 50s can be found
across the downsloped eastern foothills.

Warm air will advect into the region early today. Still expecting
above average temperatures in the 40s and 50s with mostly sunny
skies...although with cold air advection today would not be surprised if forecast
is too warm. Northwest winds will be breezy this afternoon.

Winds will become light and easterly tonight. Boundary shifts
eastward and cold air will back into the area...along with a deck of
low stratus/fog. Forecast soundings continue to indicate the
possibility of freezing drizzle with the added mention in
grids. Lows tonight will be in the 20s.

Midlevel moisture and some weak upper energy will pass over the
baroclinic zone on Thursday. Some light rain/snow is possible across
northwest into central South Dakota...with the potential for some early
morning freezing drizzle across the far northwest. Highs will range
from the 30s across central South Dakota to the 40s and lower 50s farther
west. Fog may redevelop Thursday night...but potential for freezing
drizzle looks lower. Will leave out mention for now.

Long term...Friday through Tuesday
issued at 234 am MST Wednesday Feb 10 2016

The extended forecast period features amplified active
northwesterly flow early in the period with an upper trough crossing
the northern plains during the weekend and a return to active
northwesterly flow early next week.

A northwest-southeast oriented low and middle level baroclinic zone will waver over
western and central South Dakota in response to upper level
disturbances in the nwrly flow aloft. Relatively mild temperatures
will occur to the west of the boundary with much cooler conditions
to the east. Occasional very light precipitation will be possible along
the baroclinic zone as the middle level impulses cross the region. An
upper trough will cross the area this weekend...supporting better
chances for rain and snow over the forecast area from Saturday
into Sunday especially over parts of northestern Wyoming and the Black Hills. Mild
weather will return for the beginning of next week.


Aviation...for the 12z tafs through 12z Thursday morning
issued at 234 am MST Wednesday Feb 10 2016

VFR conditions will prevail over most of the area
today...with MVFR ceilings possible over central South Dakota. IFR
conditions with areas of fog and patchy freezing drizzle will
develop over much of western and South Dakota this
evening...continuing overnight. Conditions will improve over most of
the area on Thursday morning...however IFR conditions will continue
over northwestern South Dakota.


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


Short term...pojorlie
long term...10

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