Area Forecast Discussion
Issued by NWS Sioux Falls, SD

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FXUS63 KFSD 011744

Area Forecast Discussion
National Weather Service Sioux Falls SD
1144 AM CST Thu Dec 1 2016

.SHORT TERM...(Today and Tonight)
Issued at 323 AM CST Thu Dec 1 2016

Low level moisture and clouds will remain over the area through
tonight. The upper low moving further east will leave a flat
westerly flow over the Dakotas, with a weak short wave drifting
east and arriving over the James Valley this afternoon. Current
radar suggests there are a few flurries extending through the
eastern Dakotas, even though reports are minimal. In short, all
factors are very weak except for the presence of that low level
moisture. Will linger some flurries in the area from Interstate 90
north this morning. With such a minimal and uncertain event, will
allow them to end later in the morning, but bring some back into the
James valley area this afternoon with the weak wave and mid
level moisture. Aside from little impact, this trace precipitation
potential is very tricky to deal with in terms of timing and
location. For impact purposes, the simple message is cloudy,
continued cool, and less windy. High resolution models such
as the ARW and NMM indicate there should be a few flurries, although
they do indicate more than appears to be around at present.

A little drizzle or freezing drizzle would not be out of the
question given the lack of ice with the drier air further up.
However, with no indications of that happening now here or upstream
into North Dakota with the weak radar returns, will leave out for

Flurries are not out of the question again tonight with the
continuing low level moisture. Will mention them where the chance
seems greatest in the north, or the Huron to Brookings area. Still
doubts on extent and location in such a weak event.

Temperatures will remain near normal, 30 to 35, for highs today.
Lows tonight should be a tad cooler, in the 20s, but still above

.LONG TERM...(Friday through Wednesday)
Issued at 323 AM CST Thu Dec 1 2016

Weak ridging makes a return on Friday into Friday night. Light
northwest winds on Friday will turn southwesterly overnight, then
southerly on Saturday. Stratus continues to hang on Friday, but
should slowly begin clearing or going scattered late Friday night
into Saturday. Temperatures on Friday will be similar to today, with
highs in the lower to mid 30s. With added sunshine, southerly winds,
and warming in the low/mid levels, highs will improve into the mid
30s to lower 40s on Saturday.

Northern stream trough pushes through the northern plains Saturday
night into Sunday. Initial mid level wave arrives as early as
Saturday afternoon, with a deeper trough following on its heels late
Saturday night into Sunday. Moisture remains quite limited across
the region, especially initially, becoming better focused just east
of our forecast area. Could see some light snow along our eastern
border in the Storm lake and Iowa Great Lakes area, but the bulk of
the action will be to the east.

Clouds quickly clear by Sunday afternoon behind the exiting wave,
with weak upper level ridging briefly arriving Sunday night into
early Monday. Seasonally mild temperatures persist Sunday and
Monday, improving a few degrees from the previous days.

Heading into Tuesday and beyond, confidence decreases as deep
troughing sets up to our west. Expect several waves to eject
northeast from this trough, but the timing and track of these both the northern and southern stream remain uncertain.
With models continuing to flip-flop between solutions, did not want
to stray from the blended pops for the time being. What does look
certain is that we will see some precipitation during the extended
forecast, but the timing is less certain. Temperatures do look to
turn much colder heading into the second half of the week, while any
waves that do impact the region seem likely to produce snow as the
main precipitation type. Pattern suggestions that highs in the teens
are not unreasonable by Thursday.


.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 1143 AM CST Thu Dec 1 2016

MVFR ceilings will be the prevalent feature through the TAF
period. Some potential late night and early morning to dive into
the upper IFR ceilings, and could see a few periods of flurries
tonight dip visibilities into the MVFR range as well, but with
timing uncertainty within the larger overnight window (23z-10z)
have not introduced any significant visibility reduction at this
point with expected ceiling heights.




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