189 
FXUS63 KUNR 220524
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
1024 PM MST Thu Nov 21 2019

.DISCUSSION...(This Evening Through Thursday)
Issued at 215 PM MST Thu Nov 21 2019

21z surface analysis modest high over the CWA with a few high 
clouds passing by. Snowcover on the SD plains had mostly melted. 
Leftover snow over southern Campbell County and of course, over 
the higher Black Hills. Latest water vapour loop had upper ridge 
flopping over into the northern Rockies as upper low churns over 
the far southwest.

Tonight through Sunday afternoon, quiet weather expected with a 
warming trend as downslope warming and thermal ridge wash over the 
CWA. Few breezy spots expected given isallobaric forcing at night 
and then better mixing potential during the afternoon hours.

Sunday night into Tuesday, upper trough sets up across the central 
CONUS bringing unsettled weather with chances for rain/snow as well 
as colder temperatures. Wednesday through the end of next week, most 
guidance shows split flow developing with main energy south of the 
CWA and weaker energy to the north. The evolution of this system 
continues to change, but it is important given holiday travel. No 
messaging yet, however, as confidence is very low with any 
particular solution.

&&

.AVIATION...(For the 06Z TAFS Through 06Z Friday Night)
Issued At 1022 PM MST Thu Nov 21 2019

VFR conditions are expected through the forecast period.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...None.
WY...None.
&&

$$

DISCUSSION...Helgeson
AVIATION...13