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Area forecast discussion...updated 
National Weather Service Aberdeen South Dakota
1229 am CDT Wed Oct 26 2016

issued at 1228 am CDT Wednesday Oct 26 2016

See updated aviation discussion below.

Update issued at 901 PM CDT Tuesday Oct 25 2016

Will continue to make adjustments to the forecast as rain moves
east of the region. Otherwise all other elements of the forecast
look on track with no major updates expected.


Short term...(this evening through Wednesday afternoon)
issued at 313 PM CDT Tuesday Oct 25 2016

Forecast challenges in the near term center on precipitation
coverage/timing and amounts.

Currently, under a cloudy sky and breezy southeast winds,
temperatures have climbed anywhere from 5 to 15 degrees today with
readings ranging from the mid 40s across the northeast forecast
zones to the mid 60s across the southwestern forecast zones. Also,
bands of rain and more recently clusters of elevated thunderstorms
are noted marching east-northeastward across the forecast area.

Tonight and wednesday: the ongoing precipitation event will focus
most of its accumulation across far northeast South Dakota and west
central Minnesota through late this evening before most of the
forcing/lift for appreciable precipitation amounts re-focuses off to
the south and east of this cwa. However, there is still some
potential to see a stratus field develop over some portion of the
cwa overnight and persist into the daytime hours on Wednesday.
Temperatures will be held in check tonight over areas covered by
cloudy skies. If the far western cwa manages to break out of clouds
overnight, ample surface/boundary layer moisture should work to
produce some foggy conditions by morning. Lowest low temperature
readings overnight are right now set in the upper 30s over Corson
County. Further east and south under cloudy skies, 40s for low
temperatures seems more probable. The inverse effect is expected on
Wednesday, where areas under clouds for part/most of the day will
not see much temperature recovery (low to mid 50s at best) while
areas further west are expected to see more sunshine and
temperatures warming into the 60s to perhaps near 70.

Long term...(wednesday night through tuesday)
issued at 313 PM CDT Tuesday Oct 25 2016

Not much change overall in mid and long range guidance with a
generally dry pattern of upper ridging. A pair of systems will pass
overhead, however between the deterministic GFS/ECMWF, neither
system seems to provide much for precipitation potential as best
forcing ends up outside the County Warning Area. They will have more impact on
temperatures and winds however as 850mb temperatures warm to +2
Standard deviations above climo late Thursday into early Friday.
With a 10mb pressure gradient across the state, and pressure falls
of 4-6mb/6hrs, surface winds will remain breezy Thursday night.
Despite weakening, a shift from south to southwest and then
northwest will allow for favorable mixing conditions Friday. Cloud
cover may have an impact on the temperature forecast but as it
stands forecast highs/lows Thursday/Friday already appear to be
about 20f above climo. Deterministic models share a general trend in
timing of the thermal advection pattern with mondays system, so
anticipate there will be another surge in abnormally mild air Sunday
night/Monday morning.


Aviation...(for the 06z tafs through 06z Wednesday night)
issued at 1228 am CDT Wednesday Oct 26 2016

Cigs are expected to hang in for most of the night, and probably
lower some at kabr/Katy. Improvement is expected Wednesday morning.
For kpir/kmbg fog is expected to form overnight as the clouds
dissipate. Some of that fog/cigs will lower to IFR/MVFR until mid
morning on Wednesday, with improvement thereafter.


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

short term...dorn
long term...Connelly

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