Pierre, South Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

328
FXUS63 KABR 191447
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
947 AM CDT Thu Mar 19 2026

.KEY MESSAGES...

- High temperatures will be 15 to 30 degrees above normal through
Saturday.

- Expect increased fire weather concerns over central SD through
Saturday, with winds in the afternoon gusting 20-30 mph.

&&

.UPDATE...
Issued at 928 AM CDT Thu Mar 19 2026

Fog is rapidly dissipating, with just a few pockets in the James
valley and western Minnesota. Focus shifts to temperatures and
humidity for this afternoon and any fire weather related concerns.
ARW in BUFKIT probably shows the best representation of mixing for
today (GFS too deep and NAM/RRFS too shallow) with mixed winds up
around 25-30kts. Given a warm advection regime, mixing of winds
will be less efficient so these values represent a hard cap this
afternoon, which is in line with the NBM`s upper teens to mid 20s
(kts), essentially 20-30mph which was similar to yesterday which
topped out well into the 20s to low 30s (mph). Current forecast
temperatures are close to NBM mean and while we did over-perform
yesterday, chalking that one up to a under-performance of snow
covers influence in the face of broad westerly flow enhancing
mixing of milder air aloft particularly across the east. NBM
dewpoints are also depicted to be in the 30s to as much as upper
40s. NAM does have a bit of a moist bias in its profiles and
output but the NBM/forecast is in line with most CAMS and the GFS
so its hards to suggest a more radical mixing out. As such, that
gets minimum humidity values this afternoon down around 20% for
our west river counties. Its still a relatively marginal case for
Red Flag conditions, so will continue to monitor and if we
determine there is an over-representation of model humidity will
take action then.

&&

.DISCUSSION...
Issued at 134 AM CDT Thu Mar 19 2026

With warming temperatures melting the snow across northeastern SD,
the air has filled with moisture. As dew point depressions have
decreased through the night, some areas across northeastern SD are
starting to see a little bit of fog develop. The fog potential
will continue to increase into the morning for the James River
Valley and east, leading to patchy areas of fog with lower
visibilities down to a half mile or lower at times. An eye will be
kept on webcams around the area through the morning to see if a
dense fog advisory will be needed.

An upper-level ridge continues to move east over SD for the next few
days, leading to warm air moving into central and northeastern SD.
This warm air will warm temperatures 15-30 degrees warmer than
normal for this time of the year, in the upper 50s to upper 70s. The
warmer temperatures yesterday helped to melt a lot of snow across
the area, though some areas in northeastern SD still have a bit
left. This snow will help to keep temperatures a little bit cooler
today in these areas, in the upper 50s, until the snow melts and
then highs will be in the 60s in the coming days. This warmth is
leading to a couple of maximum and warm low temperatures across the
area that get close to or above records through Saturday.

The warmth does lead to some fire weather concern into the weekend.
The moisture from the melted snow cover will be drying out from the
heat and lower relative humidity over the next couple of days,
leaving behind dry conditions that could become fairly ripe for
fires to start. Wind gusts during the afternoon are forecast to gust
20-30 mph over central SD. Conditions are not quite at red flag
criteria, but there is still fire weather concerns with the
Grassland Fire Danger index values getting up to high and very high
over central SD into Saturday.

During the weekend, a shortwave will suppress the ridge and help a
cold front to move south through SD. This cold front will cause
temperatures to drop Saturday night into Sunday and cause around
normal temperatures through the end over the weekend into next week.
The frontal passage will also provide the forcing needed for the
next chance of precipitation Saturday night into Sunday morning. Not
all of the models show precipitation occurring as the front moves
into central and northeastern SD due to the lack of moisture in the
atmosphere over the area. Despite this, more models are showing
precipitation move into northern SD, but there are still lower
chances, 20-35% chance, at the moment. Other than this,
precipitation is forecast to stay out of central and northeastern SD
for a few days.

&&

.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 638 AM CDT Thu Mar 19 2026

Terminals KABR,KATY,KPIR,KMBG

IFR/LIFR cigs and vsbys will be possible at KABR/KATY terminals
through about mid morning as a result of the patchy dense fog
occurring across northeast SD. The fog should burn off by mid/late
morning with improvements expected thereafter. VFR conditions will
return at these 2 TAF sites by midday and prevail for the rest of
the current forecast cycle. KPIR/KMBG terminals will remain VFR
for this forecast period.


&&

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

$$

UPDATE...07
DISCUSSION...12
AVIATION...Vipond