sd discuss
Office: FSD
FXUS63 KFSD 022348
AFDFSD
Area Forecast Discussion
National Weather Service Sioux Falls SD
548 PM CST Tue Dec 2 2025
.KEY MESSAGES...
- Cold, below normal temperatures continue through early next
week.
- Scattered light precipitation, a mix of snow, sleet and light
freezing rain, continue late this afternoon into later
tonight. Impacts should be minor, but be aware as you head
home this afternoon and evening.
- Wind chill values will drop to -15 to -25 in most locations
later Wednesday night into early Thursday.
- Strong southerly return flow expected Thursday which could
create some blowing snow across parts of southwest MN and
northwest IA.
- Details remain uncertain, but additional snow chances
continue this weekend into early next week.
&&
.DISCUSSION...
Issued at 220 PM CST Tue Dec 2 2025
While precipitation will overall remain light this afternoon into
tonight, the challenge will be the potential for short duration
mixed precipitation. Model soundings continue to hint that the
lowest levels will waver between all snow and occasionally the
potential for a little sleet and light freezing rain. The better
chances for this should remain and near and north of I-90 and also
over parts of south central SD. Once this wave passes overnight,
cold air will surge in behind with northerly winds rising to 15 to
30 mph overnight into Wednesday morning. With the cloud cover and
wind, temperatures will not be nearly as cold as this morning, and
should fall into the teens in most locations.
Much drier air builds into the area Wednesday which should bring
quite a bit of sunshine with some residual cumulus possibly
lingering around. With this cold, dry air building in,
temperatures may continue to fall a bit through the day or
remain steady.
The coldest time frame will be Wednesday night into Thursday morning
with cold high pressure at the surface expected to move through.
This should allow for the coldest morning of the season with lows
ranging from about -8 to -15 near and west of the James Valley. When
coupled with a light wind the wind chills may fall as low as -20 to
-25.
Strong return flow sets up on Thursday and some patchy blowing snow
will be possible, especially along the Buffalo Ridge into parts of
northwest IA. Depending upon how deep mixing gets, the 925mb layer
is indicating winds of 35 to 40 knots, which if these reach the
surface should produce some blowing snow and reduced visibilities.
Northwest flow aloft and struggles with moisture become the theme
for Friday through early next week. The better chances for
precipitation should be Saturday and Saturday night and again Sunday
night although model agreement on these weak northwest flow waves is
marginal at best. The models are coming in to a bit better agreement
for a stronger wave Tuesday into Wednesday next week sow ill need to
monitor trends with the main impacts from this potential system
being strong winds and light to moderate precipitation.
&&
.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 535 PM CST Tue Dec 2 2025
Mostly VFR conditions will transition to mostly MVFR conditions
with occasional IFR ceilings mainly due to lingering stratus.
Taking a look at satellite imagery, VFR/MVFR stratus continues
to sit over the area this evening with pockets of wintry mix and
light snow this evening. Expect intermittent periods of snow to
continue over the next several hours before things begin tapering
off after 06z (12 am).
From here, MVFR stratus will continue for the first half of
Tuesday before conditions clear with an approaching surface
high. Otherwise, westerly winds will become more northerly
overnight and breezy to end the TAF period.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
IA...None.
NE...None.
&&
$$
DISCUSSION...08
AVIATION...05
Office: UNR
FXUS63 KUNR 022317
AFDUNR
Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
417 PM MST Tue Dec 2 2025
.KEY MESSAGES...
- Snow continues into Wednesday morning, better chances for
accumulations in the northern Black Hills.
- Colder temperatures for Wednesday, followed by a warming trend.
- Active pattern brings multiple chances for light precipitation.
&&
.DISCUSSION...(This Evening Through Tuesday)
Issued at 131 PM MST Tue Dec 2 2025
Current Water Vapor and upper air analysis shows the upper trough
over western Canada dipping into the PAC NW, with northwest flow
over the FA. Surface analysis shows low over northeastern ND, with
the frontal boundary stretching into northeastern MT. Current
radar shows scattered areas of light precipitation over western SD
this afternoon. Temperatures currently sit in the 30s to low 40s
across the plains, while Black Hills temperatures are in the 20s
to mid 30s.
Areas of light precipitation will continue this afternoon, however
the better QPF chances come this evening and tonight as the
frontal boundary moves through the CWA. Weak forcing will limit
accumulations over the plains. Upslope enhancement over the
northern Black Hills will bring the best snow accumulation
chances, with HREF probability of QPF>0.5" in the 50-70 percent
range over this area. WSSI shows 30-50% probability for minor
impacts in the northern Black Hills through Wednesday morning. No
changes to the current Winter Weather Advisory in effect for the
northern hills, with 2-5 more inches possible over the next 18
hours. Precipitation will diminish late Wednesday morning, though
some weak upslope in the Black Hills may continue a little longer.
Expect a 10-15F drop in temperatures for Wednesday following
tonight's cold frontal passage. Mostly dry conditions are
expected Wednesday afternoon through Thursday afternoon, before
the next disturbance moves down out of Canada through the Dakotas.
Overall synoptic pattern will limit moisture from these
disturbances, with the better chances for accumulations remaining
in the upslope Black Hills area. Following this cooler Wednesday,
models point to a warming trend late in the week. There is some
model divergence, however it may be possible we reach back into
the 50s early next week.
&&
.AVIATION...(For the 00Z TAFS Through 00Z Wednesday Evening)
Issued At 416 PM MST Tue Dec 2 2025
More widespread precipitation chances overspread the area late
this afternoon from west to east with widespread MVFR/IFR
conditions developing, persisting into the overnight hours. LIFR
conditions will occur over the higher elevations of the Black
Hills tonight and into portions of NE WY. Conditions will slowly
improve from west to east by late Wednesday morning, after 16-18z.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...Winter Weather Advisory until 6 AM MST Wednesday for SDZ024.
WY...Winter Weather Advisory until 6 AM MST Wednesday for WYZ057.
&&
$$
DISCUSSION/KEY MESSAGES...Dye
AVIATION...SE
Office: ABR
FXUS63 KABR 022327
AFDABR
Area Forecast Discussion
National Weather Service Aberdeen SD
527 PM CST Tue Dec 2 2025
.KEY MESSAGES...
- A mix of rain, freezing rain, snow and sleet will continue into
this evening before eventually settling into a few flurries
Wednesday morning.
- Very cold air across the region Wednesday and Wednesday night,
with lows in the single digits below and teens below zero. Wind
chills may reach 15 below to 25 below zero in the James River
valley.
- Snow chances (20-40%) return Friday/Saturday and Monday as more
weather systems have the potential to move through the region.
&&
.UPDATE...
Issued at 526 PM CST Tue Dec 2 2025
We continue to monitor the light precipitation across the
forecast area, ranging from light rain around Pierre to drizzle at
Bismarck. Over our eastern counties, light snow is the main
precipitation type when it is precipitating. Small pockets of
drizzle or freezing drizzle remain possible through 06Z. The
Winter Weather Advisory for light icing remains for Spink and
Clark Counties until 9pm CT.
&&
.DISCUSSION...
Issued at 147 PM CST Tue Dec 2 2025
At 1 PM CST, vigorous warming event ongoing from west to east across
the CWA. Most of the forecast area west of Brown/Spink counties have
to or above the freezing mark. From Brown/Spink counties eastward,
temperatures are warming through the upper teens and 20s. One batch
of precipitation has moved across the CWA, producing sleet and
freezing rain, earlier, across portions of central South Dakota.
Currently, this area of light radar returns is working through the
James River valley, producing snow, sleet and freezing rain. The
temperature disparity is a warm front moving east across the CWA.
Out ahead of the boundary, winds are generally south, while behind
the boundary, winds have become breezy at 10 to 25 mph with some
higher gusts out of the west. Additional light to moderate
precipitation (rain) is working into the west river (Missouri River
valley) forecast zones at this time.
From late this afternoon through tonight, will be watching how the
low level WAA pattern affects p-type across portions of central and
northeast South Dakota until the cold front sweeping in from the
north turns off the warm air and low level CAA pushing the thermal
profile completely below the freezing mark, CWA-wide, establishing
an all snow p-type for the rest of the night. Until then, most of
central South Dakota should be warm enough through a deep enough
near surface layer to support plain rain. Further north and east
into the James River valley (and perhaps up on the Coteau in Clark
County), the zone for sleet/freezing rain potential merits
consideration for a winter weather advisory for "wintry mix" until
~03Z, when the cold fropa should cool things down to an all snow
scenario. With the cold frontal forcing and post frontal CAA, there
may be a period of time before the stratus cools down enough to
touch the DGZ and light snow/flurries could happen late tonight into
Wednesday morning. Until then, (while the stratus layer is cooling
through the 0C to -10C range, would not be shocked if light freezing
drizzle was reported falling out of the post-cold-frontal stratus
layer.
Once any lingering flurries end on Wednesday, the forecast map is
surface high pressure, with a low stratus deck over the western
forecast zones gradually making a push north and east toward the end
of the day and on into Wednesday night. Wednesday night's low
temperatures could be realized early Wednesday evening, before
increasing cloud cover and low level WAA (late) either steady
temperatures out or cause a non-diurnal temperature trend to
develop. Still seeing wind chill values Wednesday night bottoming
out between -20F and -30F.
Still seeing a positive PNA pattern in play during the out periods.
Although, by the end of the period, the western CONUS upper level
ridge appears to be flattening. The out periods are just littered
with short-lived periods of light precipitation potential.
Primarily, ensemble probabilities lean mainly snow P-type for these
systems. Although, the precipitation chances heading into Friday may
include a freezing p-type potential when low level WAA will be at a
premium. Low level thermal advection will be quite active during the
period, with the pendulum swinging back and forth from cold to warm
(on Thursday) and then cold again, briefly during the weekend, and
then possibly warm again heading into the middle of next week.
&&
.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 526 PM CST Tue Dec 2 2025
Terminals KABR,KATY,KPIR,KMBG
VFR to MVFR ceilings remain across the terminals initially. Expect
low end MVFR to IFR ceilings at ATY from 06-12Z, with a scattered
layer at 800 feet already noted by 2250Z. While other locations
could temporarily move into the IFR category, the highest/most
persistent chance is at ATY. Expect VFR conditions to return to
all sites between 14-20Z Wednesday, with the lowest return at PIR.
Winds gusts of 20-25kts out of the north are expected from late
this evening through the overnight hours.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...Winter Weather Advisory until 9 PM CST this evening for SDZ018-
019.
MN...None.
&&
$$
UPDATE...06
DISCUSSION...10
AVIATION...06
