Area Forecast Discussion
Issued by NWS Rapid City, SD

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45

FXUS63 KUNR 240434

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
1034 PM MDT TUE AUG 23 2016

.SHORT TERM...(This Evening Through Wednesday Night)
Issued at 218 PM MDT Tue Aug 23 2016

Upper level analysis has deep closed low across southern
Saskatchewan with dry west to southwest flow across the Northern
Plains. Skies are mostly sunny across the Dakotas. At the surface,
strong CAA occurring at the moment as cold front pushes southeast
and Canadian high pressure moves into Montana. Temperatures at 2pm
are in the 70s and 80s, and winds are out of the northwest at 15
to 30 mph with gusts to 40 mph.

Tonight...Surface high pressure will build into the Northern
Plains tonight. Breezy northwest winds will diminish early this
evening. With mostly clear skies and lighter winds, expect
temperatures to drop off quickly this evening with lows in the 40s
and 50s. Some 30s will be possible in the higher Black Hills.

Wednesday...Canadian upper low will slowly push east into
Manitoba as upper flow remains westerly across the area, keeping a
majority of the area mild and dry. The exception may be over the
Black Hills, where the combination of the elevated heat source and
cool air aloft may steepen lapse rates enough to promote some
isolated convection. High temperatures on Wednesday will only be
in the upper 60s to upper 70s. Partly cloudy skies and cool
conditions will be found again across the area Wednesday night,
with low temperatures falling into the 40s and 50s.

.LONG TERM...(Thursday Through Tuesday)
Issued at 218 PM MDT Tue Aug 23 2016

Mean upper trough from central Canada into the northwest US
Thursday and Friday will spin a better defined trough and
shortwave into the area Friday. Result will be increasing PoPs and
a modest shot of QPF for areas east of the Black Hills with
associated frontal boundary intersecting return flow. Temperatures
will be cooler than normal.

Saturday, given leftover moisture small leftover PoPs warranted as
shortwave ridge builds into the CWA. Have lowered temperatures some
Saturday given easterly component to boundary layer flow.

Sunday into Monday, broad upper ridge amplifies over the central US
resulting in a thermal ridge and much warmer temperatures. Dry air
suggests precipitation chances will be very low at best.


.AVIATION...(For the 06Z TAFS Through 06Z Wednesday Night)
Issued At 1032 PM MDT Tue Aug 23 2016

VFR conditions will continue through Wednesday. Increasing
mid/high cloud cover expected late Wednesday aftn and eve.


.UNR Watches/Warnings/Advisories...


LONG TERM...Helgeson
AVIATION...10 is the U.S. government's official web portal to all federal, state and local government web resources and services.