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Area forecast discussion for western South Dakota and northeastern Wyoming 
National Weather Service Rapid City South Dakota
301 am MDT Wednesday Oct 7 2015

Short through Thursday night
issued at 300 am MDT Wednesday Oct 7 2015

Current surface analysis shows frontal boundary hanging across
the area from eastern Montana...through western and south central South Dakota
and across northeast Nebraska. Upper level analysis continues to show
an upper low across Arizona...with zonal flow across the northern
rockies and most of the northern plains. A piece of energy from
the southwest low is moving north across southeast Wyoming and the Nebraska
Panhandle and into southwest South Dakota. Regional radars show the bulk of
the showers have been south of the area...but a few light showers
have moved into southwest South Dakota overnight. Otherwise...skies range
from mostly clear across northern portions of the County Warning Area to mostly
cloudy across far southern South Dakota. Temperatures are on the milder side this
morning...upper 40s and 50s. Winds are mostly light from the south
to southeast...though a weak low level jet over the area is
producing a bit more wind from northeast Wyoming into northwest South Dakota.

Unsettled weather at times will persist over the next couple of days
as a couple of disturbances pass through the area in northern stream
flow. The best chances for showers will be late tonight into
Thursday morning.

For today...skies will be partly to mostly cloudy...with the most
clouds generally over southern and eastern portions of the County Warning Area. A
few light showers are likely to linger over portions of southwest
into south central South Dakota this morning. Frontal boundary will move east
as a warm front later this morning...with warm conditions across the
area this afternoon. Highs will be the 70s...with some 60s across
the higher Black Hills. Low pressure along the boundary over
southeast Alberta will move east-southeast today and drag a weak
cold front across the area this afternoon and evening. This could
help to trigger a thunderstorm or two across mainly far eastern
portions of the County Warning Area...but the chances look lower than previously
expected. Will keep slight chance probability of precipitation mainly toward the south
central South Dakota area this afternoon and early evening...where decent cape
and instability is prognosticated...especially for this time of year. A
strong storm with small hail and gusty winds would be possible if
they develop.

A Post frontal shortwave is then prognosticated to move into the area
during the overnight and bring a chance for showers into Thursday
morning. The better chances will be from northeast Wyoming...through the
Black Hills area...and across southwest South Dakota late tonight and Thursday
morning. Have raised probability of precipitation in these areas. Will see conditions begin
to improve by the afternoon in most areas...with sunshine increasing
from northeast to southwest across the County Warning Area. Have lowered highs a bit
for Thursday...mostly 60s with some 50s over the higher Black Hills.

Long term...Friday through Tuesday
issued at 300 am MDT Wednesday Oct 7 2015

An upper level ridge will bring unseasonably warm temperatures
for Friday through Sunday. Readings will be at least 10- 15f above
normal. A fast moving cold front will bring gusty northwest winds
later Sunday/Sunday night...but moisture will be limited. Behind
the front...slightly cooler weather is expected for early next
week...but still slightly above normal.


Aviation...for the 06z tafs through 06z Wednesday night
issued at 300 am MDT Wednesday Oct 7 2015

Leftover MVFR ceilings/visibilities over far southwest South Dakota will dissipate
this morning. VFR conditions will dominate through this evening.
Isolated -shra/-tsra may occur ahead of a weak cool front late
this afternoon/early this evening well east of the Black Hills.
Another disturbance may bring a few -shra and local MVFR ceilings
overnight across northeast Wyoming/far western South Dakota.


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


Short term...26
long term...helgeson

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