Area Forecast Discussion
Issued by NWS Rapid City, SD
FXUS63 KUNR 301719
Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
1119 AM MDT Sun Apr 30 2017
.DISCUSSION...(Today Through Saturday)
Issued at 433 AM MDT Sun Apr 30 2017
Upper level analysis has large closed low over the central and
southern Plains with weak ridging over the great basin area. Skies
are mostly clear across much of the northern Plains, with the
exception of the cloud shield on the northern end of the upper low
across eastern South Dakota. At the surface, high pressure is
located across the Dakotas. Temperatures at 4 am were in the 20s
and 30s, with light winds.
Today...High pressure will remain across the area as the strong
closed upper low and associated surface low move across Kansas.
There will be a strong enough pressure gradient between these two
features to produce some breezy north winds across central and
south central South Dakota. Other than the persistent cloud shield
across south central SD and a slight chance of rain, skies should
be mostly sunny across the remainder of the area. Temperatures
will respond nicely, rising into the mid 50s to mid 60s today.
Small chances for light rain or a mix of rain and snow persist
into this evening across far south central SD, otherwise skies
will be mostly clear. Temperatures will fall into the 30s across
much of the area.
Monday...As the upper low/trof shift east of the area, fast
northwest flow will take over across the northern Plains. Weak
shortwave energy will keep just a slight chance of a shower or
isolated thunderstorm in the forecast, with some snow showers
possible across the higher elevations of the Black Hills.
Temperatures in the 50s to lower 60s are expected with breezy
northwest winds across much of the area. Variably cloudy skies are
expected Monday night, with temperatures falling into the 30s.
Fast northwest flow will keep unsettled conditions in the forecast
through mid week. Daily chances for showers are expected in many
areas, mostly during the afternoon and evening hours. A few
isolated thunderstorms also look possible Tuesday afternoon.
Temperatures will remain slightly below average through Wednesday,
with highs mostly in the 50s and lower 60s. Strong ridging is
still forecast to build into the region late in the week, with
highs rising to the 60s and 70s for Thursday through Sunday.
.AVIATION...(For the 18Z TAFS Through 18Z Monday)
Issued At 1104 AM MDT Sun Apr 30 2017
VFR conditions are expected today and through this evening for
all but south central South Dakota. There will be rain showers
moving slowly into south central South Dakota this afternoon and
continue into tonight. There will be a chance of showers over
northeastern Wyoming and into far western South Dakota, including
the Black Hills late tonight and into Monday morning. Areas of
MVFR/IFR conditions are possible with these showers.