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Area forecast discussion...updated
National Weather Service Aberdeen South Dakota
624 am CDT Sat Oct 19 2019

issued at 615 am CDT Sat Oct 19 2019

See below for an aviation forecast discussion for the 12z tafs.


Short term...(today through Sunday afternoon)
issued at 425 am CDT Sat Oct 19 2019

A quiet start to the weekend is expected as a ridge of high pressure
will maintain control of weather conditions across the area today.
Clear skies with temps falling into the upper 30s to low 40s have
been observed early this morning. The only exception to sky
condition is some lingering higher clouds across our far eastern
zones from Watertown to Ortonville. These clouds will shift eastward
closer to sunrise and leave our forecast area with mostly sunny
skies today. If there's any caveat to today it will be the breezy
conditions that will develop. Decent mixing by late morning through
the afternoon should result in breezy to windy conditions at
times...especially across the northern half of our County Warning Area. Temps top
out slightly cooler than yesterday but still will be slightly above

Overnight tonight and through the end of the period, attention will
turn to an incoming low pressure system that will bring in our next
chance of precip. Guidance progs low pressure at the sfc and aloft
to shift out of Wyoming into the northern/Central Plains on Sunday. Some
differences exist in the placement and overall track of this
feature, but they all show a trend of increasing chances for rain
showers from west to east across the cwa, particularly during the
daytime hours on Sunday. Could also see a few rumbles of thunder on
the front side of this system in our southeastern zones Sunday
afternoon. Temps will begin to cool to round out the end of the
weekend as clouds, showers and the wind machine start to kick in as
this system moves in.

Long term...(sunday evening through friday)
issued at 425 am CDT Sat Oct 19 2019

When the period opens, a large/wound up low pressure system is
churning northeast across the region. 00z model solutions continue
to support predominantly rain/liquid for p-type while precipitation
chances exist Sunday night through Monday evening. Also still looks
like plenty of wind on the back-side of the system Sunday night
through Tuesday morning.

It appears the models are changing the timing of the mid-week
clipper system. Twenty-four hours ago, the system was set to bring
precip chances to the County Warning Area from Wednesday night thru Thursday.
Tonight, model solutions appear to be speeding things up, bringing
the clipper low through the northern plains moreso in the Tuesday
night through Wednesday timeframe. But, with this low, it still
looks like p-type with initial precipitation onset is rain that
changes over to snow before precip chances go away.

The down-turn in the temperature forecast from Monday through Friday
still holds, too, as the flow pattern aloft takes on a decidedly
north-northwesterly trajectory by Monday night and remains so
throughout the period, making it more likely that airmasses working
into this County Warning Area will have their origins in Canada. It's possible,
there could be a couple of short-lived warm ups in the offing, first
Tuesday/Tuesday night out ahead of the clipper system, and then
again very late in the period Friday into Saturday before the next
blast of cooler air hits the region.


Aviation...(for the 12z tafs through 12z Sunday morning)
issued at 615 am CDT Sat Oct 19 2019

VFR conditions are expected through today and tonight for all
airports. Breezy west winds at 15 to 25 knots during the day today
will diminish overnight while switching around to the east-
southeast. Precipitation chances start to show up across the
region by early Sunday morning.


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


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