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fxus63 kfsd 182314 

Area forecast discussion
National Weather Service Sioux Falls South Dakota
614 PM CDT Fri Oct 18 2019

Short term...(this evening through saturday)
issued at 403 PM CDT Fri Oct 18 2019

The cold front is presently creeping into the far western portions
of our County Warning Area this afternoon. This boundary will continue to push to
the east overnight, and with moisture remaining mostly confined to
the mid and upper levels, not expecting much more than sprinkles, if
anything, during the overnight hours. There is a possibility of
slightly deeper moisture east of Interstate 29, and could see an
isolated shower over parts of northwestern Iowa after 06z. Will begin
to have cold air advection behind the front, and with decreasing
clouds temperatures will fall into the lower 40s over all but our far
east - with mid to upper 40s over the eastern counties of our County Warning Area.

In spite of the cold frontal passage, Saturday looks to be a decent
day with a mixy westerly flow and highs back into the lower to mid
60s. Winds overall will be relatively light, though areas from east
central South Dakota to the Iowa Great Lakes could be a little breezy with
afternoon gusts of 15 to 20 kts.

Long term...(saturday night through friday)
issued at 403 PM CDT Fri Oct 18 2019

A system is still on track to affect the area on Sunday as an upper
level trough deepens over the central Continental U.S.. there are still some
slight model differences in the handling of the system. Even so, the
general theme is the same - with rain developing over the western
portions of our area by Sunday afternoon in response to increasing
Theta E advection on a strengthening low level jet, then
overspreading the area on Sunday night into Monday as the upper
level trough swings through the region and the surface low deepens
in our vicinity. With an increasing gradient, windy conditions will
develop, especially by Monday. While temperatures will remain
relatively mild on Sunday - around 60, cooler air will feed into the
are by Monday with readings only in the 40s to lower 50s. Wrap
around precipitation now looks to linger into later on Monday night,
and as thermal profiles continue to cool, cannot rule out a brief
mix or changeover to snow over portions of southwestern Minnesota. As far
as rainfall amounts for Sunday through Monday - looking at highest
amounts north of Interstate 90, with 0.75" plus along the Highway 14

With the departure of that system, Tuesday and Wednesday of next
week will have below normal temperatures and primarily dry
conditions. Still keeping our eyes on the end of the week system,
though solutions continue to be quite varied, with GFS driving the
energy much farther to the south - with little impact to our area.
The European model (ecmwf) persists in bringing more precipitation to our area,
though offers a slightly warmer solution than previous runs -
remaining mostly rain, with some possible mix/changover north of
Interstate 90 late in the day, before ending in the evening. Will
continue to be something to keep an eye on as models trend toward
better consensus.


Aviation...(for the 00z tafs through 00z Saturday evening)
issued at 611 PM CDT Fri Oct 18 2019

Front continues to move from west to east across the region this
evening and overnight, switching winds to more northwesterly
direction behind it. Additionally, a band of sprinkles or light
rain may also briefly impact the taf sites with ksux most likely
to see precip reach the ground. VFR conditions are expected thru
the day Saturday.


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

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