973
FXUS63 KFSD 092002
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
202 PM CST Sat Nov 9 2024

.KEY MESSAGES...

- Intermittent periods of drizzle and light rain will continue
  through Sunday morning. Additional accumulations of up to a
  tenth or two will be possible. However, no snow is expected.

- While confidence is low, a few patchy areas of fog aren`t out
  of the question especially west of the James River.

- Near to just above normal temperatures will continue into the
  new week with daily highs expected to stay in the 40s and
  50s.

- Mostly quiet and dry conditions are expected for most of the
  upcoming week. However, there is some low potential (30%-40%)
  for light showers by Tuesday night into Wednesday.

&&

.DISCUSSION...
Issued at 155 PM CST Sat Nov 9 2024

REST OF THE EVENING/TONIGHT: A wet and dreary day continues! Taking
a look across the area, the dreary conditions continue as a band of
light showers rotates northwestwards along the Hwy-14 corridor
this afternoon ahead of an approaching surface low. While most
of the area is current dry-slotted due to drier air in the mid-
levels, lingering saturation in the lower levels and low LCLs
have led to intermittent pockets of drizzle developing across
northwestern IA and areas north of I-90. From here, there could
be a brief break in the light shower activity from 21z to 00z
as a touch of drier air disrupts saturation. However, this will
be short lived as low-level saturation returns with the arrival
of the surface low.

Additional light to moderate showers will likely develop around
the low as limited instability (100 J/kg) interacts with strong
PVA. From here, expect this developing activity to lift
northeastwards overnight into the Missouri River Valley and
eventually areas along and east of James River as temperatures
gradually decrease into the upper 30s to low 40s for the night.
With all this in mind, an additional tenth or two of accumulations
will be possible especially east of I-29. Lastly, with higher
dew points and lighter winds tonight; could see a few patchy
areas of fog develop west of the James River and potentially
across the Hwy-14 corridor. However, confidence is low in this
at this time.

SUNDAY & MONDAY: Heading into Sunday, lingering areas of drizzle and
light showers could persist through the first half of the day as the
surface low pushes eastwards into southern MN and northern IA.
Additional accumulations of a few hundredths will be possible
especially east of I-29. From here, cloud cover will gradually
decrease from west to east as a weak upper-level ridge moves in to
replace the departing low. With warm air advection (WAA) moving in
aloft and westerly surface flow returning for the second half of the
day, expect our mild stretch to continue as daily highs top out in
the low to mid 50s for the day.

By Sunday night, cloud cover will gradually increase as a dry cold
front sweeps through the area bringing a blast of cold air advection
(CAA) overhead heading into to Monday morning. With northwesterly
flow in place, expect overnight lows to slightly decrease into the
mid to upper 30s for the night. By Monday, cooler air will continue
to funnel into the region ahead of an approaching upper-level ridge.
With lingering CAA aloft and northerly surface flow in place, expect
our coolest temperatures of the week with highs topping out in the
40s and low 50s across the area. The cooler temperatures will
translate into the night as well as lows fall into the upper
20s to mid 30s.

TUESDAY-FRIDAY: Looking into the extended period, mostly quiet
conditions will continue through Tuesday as the warmer part of the
ridge moves overhead. Southeasterly surface winds will increase
throughout the day as the SPG tightens leading to wind gusts up to
35 mph at times. Increasing WAA along with southeasterly surface
flow will lead to a slight boost in temperatures with daily highs
likely peaking in the 50s to low 60s with the warmest conditions
along our River Valleys. Our attention will then turn westwards as a
fairly progressive shortwave trough and its associated cold front
move through the northern and central plains from Tuesday night into
Wednesday potentially bringing our next precipitation chances (30%-
40%). Looking into 09.12z guidance, most guidance has some type of
scattered rain chances developing within the WAA regime ahead of the
progressing cold front along and east of I-29.

However, with most model-derived soundings suggesting a lack of
significant moisture; its a bit difficult to say if we`ll get any
beneficial precipitation with this system. This sentiment is further
re-enforced by ensemble guidance with both the Euro and GEPS only
showing low to medium confidence (30%-50%) is up to a tenth of QPF.
From here, more amplified ridging returns from Wednesday night
onwards as quieter conditions return into the weekend. With this in
mind, expect above normal temperatures to continue with daily highs
peaking in the 50s and low 60s across the area.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1128 AM CST Sat Nov 9 2024

Mostly MVFR conditions and lower are expected this TAF period
mainly due to a combination of low hanging stratus, drizzle, and
developing showers. Taking a look across the area, areas of
drizzle and light showers continue to blanket the area ahead of
an approaching surface low this afternoon. Expect the dreary
conditions to continue into the overnight hours with most sites
keeping MVFR/IFR ceilings and vsbys through Sunday morning.
Otherwise, southeasterly winds ahead of the low will become more
light and variable overnight then northwesterly by daybreak
Sunday morning to end the TAF period.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
IA...None.
NE...None.

&&

$$

DISCUSSION...Gumbs
AVIATION...Gumbs