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fxus63 kfsd 141930 

Area forecast discussion
National Weather Service Sioux Falls South Dakota
230 PM CDT Mon Oct 14 2019

Short term...(this evening through tuesday)
issued at 223 PM CDT Mon Oct 14 2019

Filtered sunshine and warmer (although still below normal)
temperatures courtesy of weak upper level ridging in place as of mid
afternoon today. Southerly winds have also been on the breezy side.

By tonight, shortwave and attendant cold front currently noted on WV
imagery across the western Dakotas will swing into the region and
once again degrade conditions for Tuesday. Surface front looks to
push near the I-29 corridor by midnight and thru the rest of our
area prior to daybreak Tuesday. With its approach/arrival, will see
the onset of gusty winds that will continue into the daytime hours
Tuesday. Momentum Transfer off various forecast soundings shows 30
to 40 kts of wind near the top of the mixed layer so will likely see
periods of wind gusts in the 35 to 45 mph range. May also see a few
sprinkles in the warm advective Wing across SW Minnesota later this evening
into the early overnight.

Behind the front for Tuesday, will see Post frontal cloud cover
become entrenched across much of the area. Guidance somewhat
inconclusive on if there will be enough lift in this layer to allow
for any precipitation but have added in sprinkled mention for our
north and east counties with odds seemingly favoring at least
some potential. With this said, forecast soundings hint any
precipitation may very well be in the form of light drizzle
instead. Temperatures will also struggle thru the day Tuesday
with persistent cold air advection. A few locations may not even
touch 40 but most areas should top out in the 40s and have leaned
toward the ensemble mean for temperatures. Either way, with cloud
cover, gusty northwest winds and perhaps spotty light precip,
certainly a less than ideal day.

Long term...(tuesday night through monday)
issued at 223 PM CDT Mon Oct 14 2019

Wednesday should prove to be a cool day but without much wind.
Stratus will likely dissipate through the morning, but as it
dissipates higher level clouds should spread in and replace the
lower stratus. This will diminish some of the ability to warm so
highs will be well below normal. With a weak ridge of high pressure
moving through areas along and east of the James River will see
fairly light winds while areas west of the James will see southerly
winds increase to 10 to 15 mph. Temperatures will only climb into
the mid and upper 40s in many locations with 50 to 55 along and west
of the James.

Wednesday night into Thursday will see a trough of low pressure
develop to the west which will strengthen southerly flow in the low
levels. This will bring milder mornings lows and warmer afternoon
readings, although winds will likely gust to 25 mph or so Thursday
afternoon. Temperatures may actually rise a bit through Wednesday
night into Thursday morning, with sunrise temperatures around 40 to
45 and afternoon highs mostly in the 60s.

A cool front will work through the area Friday but should not have
much effect on temperatures and rainfall chances. Expect the front
to pass by dry and temperatures will still be in the upper 50s to
mid 60s for highs. Friday morning lows will also be very mild with
the stronger southerly flow, mainly mid to upper 40s.

A broad trough of low pressure will work onto the plains Saturday
night into Monday. This should bring our next better chance for
precipitation, as well as cooler temperatures. Saturday should see
increasing clouds but mild, near normal high temperatures in the
upper 50s to mid 60s. While model agreement is fairly high on a
broad trough working into the area late next weekend the strength
and placement are off quite a bit. So for now not much to talk about
other than we will keep an eye on trends the next few days to see
what this system may bring to the area. This time around things do
appear to have slowed a bit so would not doubt that the next couple
of runs will start warming things up. Taking the European model (ecmwf) and Canadian
at face value lows and highs on Sunday would likely be about 10
degrees warmer, but confidence too low to make any changes just


Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 1152 am CDT Mon Oct 14 2019

High level clouds will continue to stream overhead today along
with occasional breezy south/southeasterly winds. By later this
evening and overnight, a sharp cold front will swing thru bringing
gusty northwesterly winds. Depending on surface winds, could even
see a period of low level wind shear. Otherwise, MVFR clouds will set in by late
in the taf period, along with continued gusty northwesterly winds.


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

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