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Area forecast discussion for western South Dakota and northeastern Wyoming 
National Weather Service Rapid City South Dakota
228 PM MDT sun Oct 4 2015

Short term...this evening through Monday night
issued at 206 PM MDT sun Oct 4 2015

Upper level analysis has highly amplified flow with deep upper
lows over the southwest and southeast Continental U.S....and a weak ridge
over the southern and Central Plains. Weak trough is slowly pushing
east across the northern High Plains. Skies are cloudy across the
forecast area with just some weak showers moving through northwest
South Dakota. With the cloud cover...temperatures have struggled
into the middle 40s to middle 50s. Winds are generally light.

Cloudy and cool conditions will continue overnight. Shower
activity will generally dissipate by early this evening...with low
chances over the Black Hills. Will see more breaks in the clouds
overnight...but this could lead to at least some patchy
fog...especially southeast of the Black Hills and the plains of
northeast weak east to southeast winds persist. Lows
will generally be in the 40s.

Dry weather and more seasonable temperatures can be expected early
in the week as flow aloft becomes near zonal. Skies will be partly
cloudy in general on Monday with highs in the 60s...some 50s in the
higher Black Hills. Winds will be relatively light from the south
and southeast.

Long term...Tuesday through Sunday
issued at 206 PM MDT sun Oct 4 2015

Upper low over the desert SW/Four Corners region shifts slowly
eastward...with main upper low remaining well south of the area through
the week. However...shortwave lifts northward out of upper low
late Tuesday...and phases with digging northern stream trough. This
will bring some shower activity late Tuesday into Wednesday. Temperatures
near average for the first half of the week. Upper ridge then
develops across the western Continental U.S. For the end of the week...then
shifts into northern plains for the weekend. This will bring dry
weather with above average temperatures.


Aviation...(for the 00z tafs through 00z Monday afternoon)
issued at 206 PM MDT sun Oct 4 2015

Widespread MVFR/IFR ceilings...lowest over northestern Wyoming and the higher terrain
of far western South Dakota...expected to continue through tonight. Some areas
of IFR/LIFR visible also expected in the higher terrain. Chances for
-shra will continue to diminish.


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


Short term...15
long term...Johnson

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