Colonial Pine Hills, South Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

017
FXUS63 KUNR 111050
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
450 AM MDT Wed Jun 11 2025

.KEY MESSAGES...

- There is a marginal risk (level 1 of 5) for isolated severe
  thunderstorms across northeastern WY this afternoon and evening.
  Main threats are hail and damaging winds.

- There is a slight risk (level 2 of 5) for scattered severe
  thunderstorms across northeastern WY and southwestern SD Friday.
  Main threats are large hail and damaging winds.

- Active weather continues through the weekend with near daily
  chances for showers and storms.

&&

.DISCUSSION...(Today Through Tuesday)
Issued at 318 AM MDT Wed Jun 11 2025

06z sfc analysis depicts cold front draped across southern SD. A
line of weak showers is moving across the western SD plains with a
couple of showers along the SD/NE border producing a few
lightning strikes. This wave pushes east through this morning with
weak subsidence behind the wave settling over the CWA and a
frontal boundary stalling out over the region. This subsidence
should keep things dry for western SD through most of today. Smoke
from wildfires in Canada will also settle back into the region
today, especially across the western SD plains.

The next wave moves across the Rockies and into the Northern
Plains later this evening into tonight. Corridor of 1000-1500 J/kg
ML CAPE develops along the stalled out front as theta-e ridge
builds over northeastern WY. Deep layer moisture will also support
stronger convection than yesterday. Upper level winds aren`t too
strong so bulk shear will be the limiting factor with 0-6km bulk
shear values at around 30-40kt for northeastern WY by this
afternoon. However, the instability and shear should be enough to
support an isolated wind and hail threat later this afternoon.
Convection shifts east overnight as the main wave makes it into
the region.

Frontal boundary pushes further southwest Thursday with cooler
airmass moving into the region. A marked temperature gradient will
set up over the CWA with highs in the mid 60s across the northern
half of the CWA and highs in the 80s across the southern half.
Things will gradually dry out from west to east as the wave exits
the region, though diurnal instability over the Black Hills may
support some afternoon showers on Thursday.

The frontal boundary will remain stalled out over the region
through this weekend into next week with low level southerly flow
advecting gulf moisture into the region in the vicinity of the
front. This will potentially support rounds of severe weather over
the weekend beginning on Friday when the first of many impulses
riding along upper level WSW flow impacts the region. There is a
slight risk (level 2 of 5) across northeastern WY and southwestern
SD for Friday afternoon with large hail and damaging winds being
the primary concerns.

&&

.AVIATION...(For the 12Z TAFS Through 12Z Thursday Morning)
Issued At 445 AM MDT Wed Jun 11 2025

There is a chance for showers and storms (with associated LCL MVFR
conditions and gusty and erratic winds) this afternoon and
evening across northeastern WY into the Black Hills. This
shower/storm activity will move east through the evening into
tonight. Otherwise, VFR conditions largely expected through
tonight. MVFR/IFR conditions may develop across the western SD
plains into the Black Hills late tonight into early tomorrow
morning.

&&

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

$$

DISCUSSION/KEY MESSAGES...Wong
AVIATION...Wong