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fxus63 kfsd 231944 
afdfsd

Area forecast discussion
National Weather Service Sioux Falls South Dakota
244 PM CDT Fri Aug 23 2019

Short term...(this evening through saturday)
issued at 244 PM CDT Fri Aug 23 2019

Forecast trends for this cycle...

Models continue to slow the eastward track of precipitation this
weekend.

Mid week cool down still on target next week but may have one
warm/mild day mixed in with the below normal temperatures.

High pressure firmly in control of conditions tonight into Saturday
with fairly deep southeast flow up to around 850 mb through Saturday
evening. This will keep the northwest advection of the drier and
more stable air to the east and likely keep most shower activity in
central South Dakota and points west. While winds will be a bt stronger
tonight low temperatures will still be on the cooler side with drier
air in place. Lows should be 55 to 60 in northwest Iowa and the mid
60s west of the James River.

On Saturday the southerly surface pressure gradient will increase
and so will the winds. Expect some gusts around 35 to 30 mph through
the day. Upper level support will slowly drift east and a few
showers could creep into central SD, but chances remain low. East of
the James River partly to mostly cloud skies and breezy conditions
will couple with highs in the 70s for a nice late August day.

Long term...(saturday night through friday)
issued at 244 PM CDT Fri Aug 23 2019

On Saturday the southerly surface pressure gradient will increase
and so will the winds. Expect some gusts around 35 to 30 mph
through the day. Upper level support will slowly drift east and a
few showers could creep into central SD, but chances remain low.
East of the James River partly to mostly cloud skies and breezy
conditions will couple with highs in the 70s for a nice late
August day.

Upper level support struggles to shift east Saturday night so will
keep chance for showers and thunderstorms west of Interstate 29 for
now. Not expecting heavy rain or severe weather at this time, but if
showers can develop they may be briefly efficient with respect to
heavy rain potential.

The best chance for showers and thunderstorms will come Sunday night
into Monday as the main wave deepens and ejects eastward. Still a
lot up in the air regarding what will actually happen but there
should be a little more instability and shear to bring a small
threat for severe weather.

Cooler air will move in on Monday, but just when on Monday is still
in question. If the cooler air comes down late Sunday night into
Monday morning then it will likely be cooler and breezier.

Some mixed signals for mid to late week with regards to the much
below normal temperatures expected. While temperatures will still
likely be below normal on Monday and Tuesday there are some
indications of the upper level trough shifting east with some
ridging possible Wednesday into Thursday. If this happens it could
warm pretty nicely, especially on Thursday. Still 6 days out so not
jumping to any conclusions but we may see a mid week warm up, then
all indications are for another cool front Thursday night which
would bring temperatures below normal again Friday through about
Sunday. Bumped highs up closer to the 50th percentile on Thursday as
the nbm forecast was in the 10th percentile. Confidence in
precipitation Tuesday through Friday is pretty low as timing of the
troughs and ridges is pretty low.

&&

Aviation...(for the 12z tafs through 12z Saturday morning)
issued at 625 am CDT Fri Aug 23 2019

Low-end VFR to MVFR stratus/stratocu expected near and west of the
James River Valley through much of the taf period. MVFR ceilings
could occasionally brush khon, but think majority of this taf
period will see ceilings above 3kft above ground level. This area also most
likely to see occasional south-southeast gusts to 20-25kt late
this morning through sunset.

VFR conditions will prevail east of the James River Valley
through this evening, with a potential for MVFR ceilings working
eastward toward the I-29 corridor late in this taf period.

&&

Fsd watches/warnings/advisories...
South Dakota...none.
Minnesota...none.
Iowa...none.
NE...none.
&&

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