Area Forecast Discussion
Issued by NWS Rapid City, SD

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FXUS63 KUNR 170500

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
1100 PM MDT Sun Oct 16 2016

Issued at 703 PM MDT Sun Oct 16 2016

Winds decreasing and relative humidity increasing this evening.
All observation sites no longer meeting Red Flag criteria.
Therefore, have let the Red Flag Warning expire.


.SHORT TERM...(This Evening Through Monday Night)
Issued at 209 PM MDT Sun Oct 16 2016

1930z surface analysis shows a strong 990mb low over southwestern
Saskatchewan with a surface trough and cool front draped across
the northern plains. The surface trough has cleared most of the
western and central portions of the CWA at this hour, with gusty
southwest to westerly winds and 2-3mb/3hr pressure rises behind
the surface trough. Most wind gusts have been in the 40mph to
50mph range, but KSPF did reach up to 59mph at 1115am MDT this
morning. Winds will remain breezy to windy the rest of the
afternoon, and should start to subside by sunset.

Late this afternoon through tonight, models develop a narrow band of
precipitation associated with an area of lift/frontogenesis oriented
from southwest to northeast across the CWA. As a shortwave trough
approaches from the west, areal coverage of precipitation will
increase for northern and western portions of the CWA.

Afternoon high temperatures on Monday could be a bit tricky. NWP
guidance keeps precipitation/clouds over northwestern South Dakota
and northeastern Wyoming most of the day, while south-central South
Dakota remains mostly clear and dry. This results in about a 20
degree temperature gradient between northwest and southeast portions
of the CWA. Changes in the forecast position of the
precipitation/clouds could result in afternoon highs being too

Winds are also looking to be breezy across portions of southwestern
South Dakota Monday afternoon, and should approach wind advisory
criteria. As a result, a wind advisory has been issued for Fall
River, Oglala Lakota and Bennett counties.

Showers/clouds push east of the region after midnight as drier air
advects into the region. Lows Monday night will range in the mid 30s
in northeastern Wyoming to mid 40s across south-central South Dakota.

.LONG TERM...(Tuesday Through Sunday)
Issued at 209 PM MDT Sun Oct 16 2016

Near average temperatures will continue from Tuesday through
Thursday with slightly warmer than average highs on Friday and
Saturday as a broad upper ridge builds over the western CONUS.
Moisture will be limited, but there could be a few light showers
mainly across the southern parts of the forecast area on Tuesday
night and Wednesday as an upper level trough traverses the
Northern Plains. Cooler air to the north may sag southward into
far northeastern Wyoming and northwestern South Dakota on Saturday
night, creating a small chance of showers along the frontal zone
Saturday night into Sunday, with slightly cooler high temps on


.AVIATION...(For the 06Z TAFS Through 06Z Monday Night)
Issued At 1059 PM MDT Sun Oct 16 2016

Scattered showers are expected over northeastern Wyoming, the
Black Hills area and northwestern South Dakota overnight into Monday.
Locally MVFR conditions will be possible with the showers,
otherwise VFR conditions are expected.


SD...Wind Advisory from 11 AM to 6 PM MDT Monday for SDZ041-042-044.



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