Winner, South Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

193
FXUS63 KUNR 091730
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
1130 AM MDT Wed Apr 9 2025

.KEY MESSAGES...

- Chance for showers and a thunderstorm or two this afternoon, mainly
  from the Black Hills into southwest SD. Wind advisory across
  northwest SD this afternoon for gusts to around 50 mph.

- Warmer and dry conditions late late week into Saturday. Elevated
  fire weather conditions expected in some areas today through
  Saturday.

- Pattern shift towards the end of the weekend will lead to cool,
  windy, and unsettled weather into early next week.

&&

.DISCUSSION...(Today Through Tuesday)
Issued at 300 AM MDT Wed Apr 9 2025

Current surface analysis shows one area of low pressure over
eastern NE, with another area of low pressure over far southern
SK. Passing cool front is well south and east of the region now,
with most of the showers dissipating and exiting the area. Upper
level analysis shows west-northwest flow across the region, with a
developing area of low pressure across southeast SK moving east-
southeast. Skies are variably cloudy with temps mostly in the
upper 30s and 40s. Winds are relatively light from the west or
northwest in most areas.

As the low to the north passes northeast of the area today, a
tightening pressure gradient to the south will lead to gusty
northwesterly winds across much of the northwest to central SD
plains. The strongest winds look to be across northwest SD, where
some gusts of over 45 mph are likely (near or above 60 percent)
during the midday and afternoon hours. Previously issued wind
advisory looks good for those areas. Weak energy aloft could be
sufficient to produce Isolated to widely scattered showers and
possibly a thunderstorm or two from the Black Hills area to
southwest SD this afternoon. Very little CAPE is forecast for the
area, generally less than 200 j/kg, but some gusty winds could
accompany a stronger shower/storm. Highs today will mostly be in the
mid 50s to mid 60s, cooler over the higher Black Hills. Most of the
activity should taper off and end by early evening, with winds
diminishing some as well. Would not rule a stray light shower
tonight in some areas, especially across northwest SD, but chances
look less than 15 percent right now. Lows tonight will mostly be in
the 30s to near 40 degrees.

Breezy conditions will develop Thursday morning as temps rise toward
the upper 50s and 60s in the afternoon under mainly sunny skies.
High pressure will gradually move in from the west, allowing winds
to gradually decrease during the afternoon from west to east. As
surface high eventually moves east of the area Thursday night, winds
will switch to the south-southeast and help to bring warmer air in
for Friday and Saturday. Building ridge over the Rockies late week
will move over the Plains Friday into Saturday. Highs will be well
above average, 70s to lower 80s in most areas each day, warmest
south and southeast of the Black Hills. As the ridge shifts east of
the area over the weekend, the next cold front and shortwave trough
will approach the area later Saturday night and Sunday. Chances for
showers and some higher elevation snow showers will start to
increase Saturday night and persist across much of the area Sunday
into Monday. The better chances for pcpn will mostly be from
northeast WY to the northern Black Hills and northwest SD. The front
will bring much cooler air and gusty winds Sunday and Monday. At
this point, shortwave ridge is progged to build into the region
toward midweek, with warmer and drier conditions likely to return.

&&

.AVIATION...(For the 18Z TAFS Through 18Z Thursday)
Issued At 1128 AM MDT Wed Apr 9 2025

Isolated showers have begun to re-develop across the Black Hills
and portions of NE WY. Local MVFR conditions may briefly occur
with any stronger cores. Confidence is low that any impacts will
occur at KRAP or KGCC this afternoon so have kept shower/thunder
mention out of TAF. Northwest winds will gust around 45kts over
northwestern SD 17z today to 01z this evening. Otherwise, expected
VFR conditions through the period.

&&

.FIRE WEATHER...
Issued At 300 AM MDT Wed Apr 9 2025

Elevated fire weather conditions can be expected in some areas
from today through Saturday. Gusty winds today will lead to high
to very high grassland fire danger across the western and south
central SD plains. Minimum relative humidity will be down to 15 to
around 20 percent in many areas on Thursday and Friday, as well
as some southern areas on Saturday. Breezy conditions on Thursday
will lead to elevated and possibly near critical conditions in a
few areas of the western SD plains.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...Wind Advisory until 7 PM MDT this evening for SDZ001-002-012>014-
     073-078.
WY...None.
&&

$$

DISCUSSION/KEY MESSAGES...26
AVIATION...SE
FIRE WEATHER...26