Milbank, South Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

617
FXUS63 KABR 291424 AAB
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
924 AM CDT Thu May 29 2025

.KEY MESSAGES...

- Wildfire smoke from Canada will plunge southward into the region
  this evening and continue through at least Friday. Most of the
  smoke is expected to remain aloft and is not expected to reach
  the surface for now.

- Slow steady warmup with highs in the 70s today, upper 70s/80s Friday,
  and peaking Monday in the 80s to near 90 (5 to 15 above).

&&

.UPDATE...
Issued at 923 AM CDT Thu May 29 2025

No changes planned to the today period forecast.

UPDATE Issued at 645 AM CDT Thu May 29 2025

The aviation discussion has been updated below for the 12Z TAFS.

&&

.SHORT TERM /TODAY THROUGH FRIDAY AFTERNOON/...
Issued at 359 AM CDT Thu May 29 2025

As of 4am, water vapor imagery indicates the upper level low over
central SD and extending eastward through MI. Within this flow,
several little vortices continue to spin around the low from central
SD into MN. Mid to high clouds from these continue to move from
northeast to southwest into the eastern half of the state, which
will continue through the morning. Otherwise, current temps range in
the 40s with dewpoints fairly similar. Like the last couple of
mornings, per light winds and narrow dewpoint depressions, patchy
fog is possible across the CWA and dissipating a few hours after
sunrise.

HREF along with ENS/GEFS having this closed low opening into a
positive tilted wave as it will continue to track southeastward,
with the axis of the wave from the Great Lakes through KS by 00Z
Friday. At the surface, high pressure remains dominant over the
Northern Plains through the Southern Plains today and tonight. Just
like the past few days, diurnally driven elevated showers are
possible over the far eastern CWA this afternoon as soundings show
very skinny elevated CAPE, indicating there could be enough oomph to
produce these showers (and maybe a couple lightning strikes). Few of
the CAMs highlight this chance (mainly the HiRes and NSSL WRF),
however not as numerous, so left the 15% chance of pops in for this
area. The other concern will be the return of the smoke from Canada
as winds aloft will be turning northerly this evening. HRRR
vertically integrated smoke model indicates this southward plunge of
smoke hitting the CWA this evening and continuing through at least
Friday, with possibly even thicker plumes of smoke moving in Friday
afternoon and evening. This has been incorporated into the Sky grids
from 00Z Friday to 00Z Saturday. Most of this looks to stay aloft as
near surface smoke model does not suggest anything hitting the
surface as of now. Otherwise, dry weather expected for Friday as the
high dips a bit south, with the Northern Plains on the northern
ridge of it. Aloft a shortwave moves over the crest and down the
ridge (off to our west) and over the Northern Plains by late Friday.

Winds will be light today and tonight, however, west/southwest flow
of winds at the surface over the eastern CWA may lead to very
marginal downsloping winds on the eastern side of the Coteau early
Friday morning as HRRR and NBM suggests this, with gusts of 20 mph.
These gusts will spread eastward through Friday afternoon into MN.
Temps for today be warmer, running in the upper 60s to the mid 70s,
which is around normal. NBM 25-75th spread for MaxT is 2 degrees or
less, giving higher confidence on these temps. Lows are forecasted
to range in the upper 40s to the lower 50s with a spread of 2-4
degrees. 850mb temps Friday will warm to +14 to +18 with surface
temps warming in the upper 70s to the lower 80s with a spread of 2-4
degrees. However, with the smoke and depending on the thickness, it
may knock off a couple of degrees, so there is less confidence in
how warm we get for the high temperatures.

&&

.LONG TERM /FRIDAY EVENING THROUGH WEDNESDAY/...
Issued at 359 AM CDT Thu May 29 2025

The overall upper flow pattern expected to play out in this period
remains largely unchanged from previous couple of forecast package
issuances. Starting Friday night into Saturday, shortwave ridging
aloft over the Northern Plains will be knocked down just a bit by a
shortwave trough that is progged to move up and over a more
amplified upper ridge across the Northern Rockies/High
Plains/Western Canada. GEFS/GEPS/EC ENS all pick up on this feature
but placement and strength still varies among the guidance. BUFKIT
soundings still show a mostly dry column with perhaps an uptick in
some mid level moisture but is now absent from any skinny CAPE that
they once depicted for Saturday. Latest NBM PoPs still came in
nearly close to zero as one can get and thus will retain a dry
forecast at this time. What this feature will do is push a sfc cold
front through the area on Saturday switching our low level flow back
to the northwest. As mentioned in the short term section, Canadian
wildfire smoke in the mid to upper atmosphere will have drifted
south into our region. Persistent northerly flow aloft will continue
to promote the continued presence of smoke with perhaps some working
down closer to the sfc in the post-frontal air mass Saturday.

We`ll turn up the heat by the end of the weekend into early next
week as a highly amplified upper ridge translates east and across
our region Sunday into Monday. 850mb temps will top out in the upper
teens to low 20s C Sunday and Monday. Latest NBM probabilities of
seeing temperatures reach or exceed 90 degrees still favor our
eastern zones Sunday and Monday but moreso on Monday as a sfc cold
front starts to impinge on our western zones. Ranges currently stand
at 30-50% from the James Valley and points east into west central
MN. During the early portion of next week, an upper low/trough is
progged to dig south across the PacNW and Great Basin. This will
lead to southwest flow aloft across the Northern Plains and likely
improve any leftover smoky conditions. It will also feature a series
of disturbances rolling through the region that will give us daily
chances for showers and storms beginning Monday night and persisting
through the end of the period. Continuing to monitor trends for
severe weather potential early next week with a cold fropa. Still
difficult to advertise any specifics but the presence of increasing
instability and adequate shear by the latter half of Monday into
Tuesday at the time of the fropa could lead to some active weather
across the region.

&&

.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 645 AM CDT Thu May 29 2025

Terminals KABR,KATY,KPIR,KMBG

Patchy fog is dotting the landscape again this morning, but as in
previous days, it should be short-lived early on in this TAF
cycle. KABR/KPIR may drop into MVFR/IFR vsbys briefly this morning
before the fog burns off for good. All terminals are expected to
remain dry today, but KATY would stand the best chance for a stray
shower this afternoon, where an isolated chance (15%) is
possible. Left mention of it out of the forecast at this time.
Surface high pressure overhead will lead to a light wind outlook
in this TAF valid period. Wildfire smoke drifting into the region
from the north is still slated for later this evening into the
overnight and likely to persist through Friday. Most of this is
expected to remain aloft through that time frame.

&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
&&

$$

UPDATE...10
SHORT TERM...MMM
LONG TERM...Vipond
AVIATION...Vipond