Scientific Forecaster Discussion
fxus63 kunr 232039
Area forecast discussion for western South Dakota and northeastern Wyoming
National Weather Service Rapid City South Dakota
239 PM MDT Fri Jun 23 2017
Discussion...(this evening through friday)
issued at 238 PM MDT Fri Jun 23 2017
Broad upper trough remains across the central Continental U.S. Today with an
upper level just north of North Dakota. Base of the upper trough/jet
is pushing across East River into the upper Midwest. Strong and cool
Canadian surface high pressure is sitting across eastern Montana
into the Dakotas into the central Great Plains. Temps as of 20z are
in the mid 60s to mid 70s...and 50s to lower 60s over the Black
Hills. Temps will continue to be cool tonight through Sunday as
surface high slowly drifts eastward. Lows tonight will again range
from the mid 30s over the Black Hills to low/mid 40s over the
plains. Partly to mostly sunny skies will also continue through the
weekend. Highs Saturday will be in the upper 60s to mid 70s over the
plains...and upper 50s to mid 60s over the Black Hills. Temps Sunday
will be 3-6 degrees warmer than Saturday. Warmer air will advect in
for the beginning of the work week as southerly return flow sets up.
Highs will reach the upper 70s to upper 80s Monday...then mid 80s to
mid 90s Tuesday as southerly flow ramps up and upper ridging sits
across the northern plains. This could bring the next chance for
precipitation...though an overall drier pattern is still expected.
Models are showing better chances of storms toward the middle of the
week as an upper trough crosses the region along with a cool front.
It generally looks to be a more active pattern for the second half
of the week.
Aviation...(for the 18z tafs through 18z saturday)
issued at 1057 am MDT Fri Jun 23 2017
Other than some local MVFR cigs over the higher blkhls this aftn,
VFR conditions expected across the area through tonight. Gusty
northwest winds will diminish this evening.