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 46 47 48 49 50

564
FXUS63 KUNR 292337
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
537 PM MDT MON AUG 29 2016

.SHORT TERM...This Evening Through Tuesday Night
Issued at 329 PM MDT Mon Aug 29 2016

Surface cold front almost stationary across south central SD,
still draped between PIR-9V9 and PHP-VTN. Upper low over srn CO-
nrn NM is drawing moisture northward ahead of it into central
Plains, with some thunderstorms developing over Cherry Co NE along
the cold front that may clip south central SD late afternoon and
early evening. Surface high pressure is pushing southward through
the Dakotas, with northeast winds bringing cooler temperatures to
the forecast area.

Upper ridge builds over the northern Plains through midweek...giving
the forecast area mostly dry conditions. CAPE values ov 1000-
2000j/kg over the Black Hills Tuesday and upslope flow may produce
some thunderstorms in the afternoon, but higher CIN will inhibit
convection for the plains. With lee trof developing over MT Tuesday,
south winds will warm temperatures in the western zones, but highs
will be cooler over central SD where east-southeast winds will
prevail.

.LONG TERM...Wednesday Through Monday
Issued at 329 PM MDT Mon Aug 29 2016

The upper level ridge will increase in amplitude over
the Rockies and the high plains over Wednesday as an upper trough
deepens over the west coast. The will lead to warm temperatures and
dry weather through Thursday. The surface pressure gradient
indicates that breezy to windy southeasterly winds will develop,
which should keep minimum relative humidities in the 20 to 30
percent range over western South Dakota. The RH will be lower over
northeastern Wyoming, ranging from 15 to 25 percent on Wednesday and
Thursday. Southwesterly flow aloft will develop on Friday as the
ridge and the upper trough both shift slightly eastward. This will
result in cooler temperatures for the weekend as well as better
chances for showers and thunderstorms.

&&

.AVIATION...(For the 00Z TAFS Through 00Z Tuesday Evening)
Issued At 536 PM MDT Mon Aug 29 2016

Lingering showers and thunderstorms over portions of northeast WY
and south central SD will dissipate early this evening. VFR
conditions are expected overnight into Tuesday morning. There will
be a chance for showers and thunderstorms Tuesday afternoon over
the Black Hills.

&&

.UNR Watches/Warnings/Advisories...
SD...None.
WY...None.
&&

$$

SHORT TERM...55
LONG TERM...10
AVIATION...26



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.