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Area forecast discussion for western South Dakota and northeastern Wyoming 
National Weather Service Rapid City South Dakota
1035 PM MDT Wednesday Apr 23 2014

Update...
issued at 554 PM MDT Wednesday Apr 23 2014

Winds continue to diminish across western South Dakota. Will let
Wind Advisory expire. Rest of forecast looks good.

&&

Short term...this evening through Thursday night
issued at 242 PM MDT Wednesday Apr 23 2014

An upper level trough is moving into the central US...with
southwest flow over the northern plains. Skies are gradually
clearing as the system pushes clouds eastward. Surface trough sits
over western South Dakota...with the cold front slowly making its
way through the area. Northwest winds have taken a little longer
than expected to become gusty...but have finally picked up this
afternoon. Showers continue to move northeastward through central
South Dakota.

The upper wave will continue passing through the northern plains
tonight into Thursday...with the upper low and most of the energy
north of our County Warning Area. May be a few lingering showers across northeast
Wyoming this evening. At the surface...the trough will push east
overnight. The pressure gradient will tighten a bit across western
South Dakota between high pressure over Wyoming/Colorado and the exiting trough.
Northwest winds may become breezy again across northwest South
Dakota on Thursday...although recent model runs have toned speeds
down. Mav is showing barely Wind Advisory criteria across the
northwest...with the met under criteria. At this point do not think
a Wind Advisory will be necessary...but later shifts can reanalyze.
Decreased winds in the grids...although they still might be a little
too strong.

Upper ridging will push into the region Thursday...bringing drier
air and partly cloudy skies. High temperatures will be near or slightly
above seasonal averages in the 60s...50s in the hills. Lows Wednesday
and Thursday nights will be mainly in the 30s.

&&

Long term...Friday through Wednesday
issued at 242 PM MDT Wednesday Apr 23 2014

Upper ridge axis crosses the region Friday bringing mild and dry
conditions to the area.

Focus then turns to a strong upper trough working through the west
early in the weekend...and into the plains later in the weekend and
early next week. Models have been slowing the timing of this
system...with cooler air now filtering in Sunday. Widespread precipitation is
still prognosticated to begin Sat night and continue through Monday. Models
show upper low crossing the Colorado area Sunday...then slowly cross
the Central Plains. Coldest air will be over the Great Lakes
region...so not much access to a colder airmass will likely keep
precipitation as rain instead of snow...except maybe during the nighttime
hours Sunday night and Monday night. The higher elevations of the
Black Hills will have the best chance to see snow. European model (ecmwf)/GFS agree
with liquid quantitative precipitation forecast amounts of an inch or more.

&&

Aviation...(for the 06z tafs through 06z Thursday night)
issued at 1033 PM MDT Wednesday Apr 23 2014

VFR conditions expected through Thursday evening. Gusty west to
northwest winds will spread across the area Thursday morning and
continue through Thursday afternoon.

&&

Unr watches/warnings/advisories...
South Dakota...Fire Weather Watch from Thursday afternoon through Thursday
evening for sdz263>266.

Wyoming...none.
&&

$$

Update...7
short term...pojorlie
long term...13
aviation...7