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fxus63 kfsd 120500 

Area forecast discussion
National Weather Service Sioux Falls South Dakota
1100 PM CST Mon Nov 11 2019

Short term...(this evening through tuesday)
issued at 241 PM CST Mon Nov 11 2019

..main focus this forecast package will be how cold to go tonight
and the potential mixed precipitation event late Tuesday night into

The diurnally driven cumulus and flurry activity will quickly
diminish from 23z to 1z this evening, giving way to mostly clear
skies and a decreasing wind. With cold temperatures already in place
this afternoon this should bring an environment supportive for
fairly cold low temperatures. The exception will be along and west of
the James River where southerly return flow will begin to develop.
Will aim for slightly below zero in parts of far eastern SD,
northwest Iowa and southwest Minnesota, and around 5 above along and west
of the James River. Will likely see steady to rising temperatures
late there as well.

Strong southerly flow is expected Tuesday as the next system digs
into the northern rockies. This will bring temperatures up a bit,
but still well below normal. Anticipate 20s for highs in most
locations with 30s along and west of the James River.

Long term...(tuesday night through monday)
issued at 241 PM CST Mon Nov 11 2019

Tuesday night very strong warm air advection develops aloft but
right now the layer is far too dry to support snowfall, so not
anticipating much in the way of precipitation. The exception could
be near south central South Dakota where the environment could saturate
shortly before 12z. This would also be a challenge as the
precipitation would likely be mixed. Will need to keep a close eye
on Tuesday night into Wednesday morning. If the system ends up with
a little more moisture than expected, some freezing precipitation
will be possible. Did raise lows to around the 75th percentile
Tuesday night with strong winds, warming low levels and increasing
cloud cover.

A fairly compact system will dive south on Wednesday and bring a
good chance for light snow. Current forecast soundings not as
favorable thermally as this past event with the dendritic layer
shoved up to about 500 mb to 600 mb. So any loss in saturation above
about 700 mb would bring an end to the snowfall. And even on
Wednesday this system could pose some mixed precipitation issues but
too early to have any real confidence on this. Will see some warmer
air aloft ride over the colder air but may also see surface
temperatures climb a little above freezing. Fairly dry in the warm
layer as well. For now the better potential would be roughly along
and southwest of a Brookings to Sioux City line for mixed
precipitation. Temperatures will be a bit more mild on Wednesday
with most locations topping out from 30 to 35 degrees.

Thursday into Friday will see temperatures rebound as weak upper
level ridging spreads across the area. This will bring highs in the
30s to lower 40s Thursday then 40s everywhere on Friday. The next
system will move through on Saturday and for now looks like nothing
more than a broad unfocused upper level trough bringing only small
chances for precipitation. Outside of this small chance for
precipitation temperatures will finally be at or above normal for an
extended period from Saturday into Monday.


Aviation...(for the 06z tafs through 06z Tuesday night)
issued at 1059 PM CST Mon Nov 11 2019

VFR conditions through the period. Strong surface wind gusts to
around 25 kts likely from later morning through the afternoon. By
evening, low-level wind shear conditions will develop for ksux as
winds decouple and the low-level off-surface winds increase and


Fsd watches/warnings/advisories...
South Dakota...none.

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