Area Forecast Discussion
Issued by NWS Sioux Falls, SD

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FXUS63 KFSD 141800

Area Forecast Discussion
National Weather Service Sioux Falls SD
100 PM CDT Fri Oct 14 2016

.SHORT TERM...(Today and Tonight)
Issued at 402 AM CDT Fri Oct 14 2016

At 08z, a little higher based stratus starting to sneak up into the
lower Missouri valley, an offshoot of larger mass of stratus to the
south. Northward push today will be a bit problematic as gradually
increase mixing, especially for the lower stratus forming across
central KS pulled northward with strong southerly low-level jet.
Will also have fact that flow aloft picks up in an increasing
southwest component which should begin to divert the more
significant portion of the leading cloud mass eastward into Iowa and
Minnesota east of the CWA. With either the spectre of clouds or flow
from more cloudy areas, temps this afternoon will be somewhat
restrained in the mid to upper 60s in parts of northwest Iowa.  To
the west, only a few higher clouds will impact, and unseasonably warm
with temps with 70s, and even lower to mid 80s west from the James
Valley westward.

Whatever the end result in for the day period, there is little doubt
that stratus will move en masse northward this evening, and blanket
all but the far western CWA overnight. A nicely sheared layer atop
the low level moisture suggests that drizzle will be possible, and
perhaps even some fog as stratus lowers toward areas of higher
terrain near/east of I-29. Very mild temps tonight with wind/clouds,
likely not far below normal highs in the mid 50s to around 60.

.LONG TERM...(Saturday through Thursday)
Issued at 402 AM CDT Fri Oct 14 2016

Stratus still looks on target for Saturday, especially east of the
James River. Kept highs a little cooler over northwest Iowa where it
looks like the stratus will hang in the longest. The Consraw output
seemed to have the best handle on this. Will have some patchy light
drizzle in northwest Iowa as well but the chance for any rain or
measurable precipitation looks very unlikely. May in the end see a
better chance for fog than drizzle. Cooler air will settle in
Saturday night which should erode the stratus and push it to the
southeast. Lows in the mid 40s to lower 50s looks reasonable.

Sunday will be a rebounding day as east and southeast winds turn
more southerly. Will stick closer to CONSMOS for winds on Sunday as
Superblend looks to low with increasing gradient. Nice and warm with
highs in the 70s.

Very warm on Monday with temperatures well above normal. Highs in
the mid 70s to lower 80s.

Southwest flow aloft with the strongest energy to the north supports
a mainly dry Monday through Thursday time frame, even with a fairly
strong cool front moving south into the are Monday night. Tuesday
will be breezy and cooler with temperatures likely below normal
Wednesday and Thursday along with north to northwest winds likely
about 10 to 20 mph.


.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 100 PM CDT Fri Oct 14 2016

MVFR stratus streaming north out of the Central Plains will slide
through far southeast corner of the forecast area to start the
period. Expect this stratus to remain east of KSUX, but will likely
affect KSLB area for a few hours.

Stratus will expand north-northwestward through the night, affecting
locations along and east of the I-29 corridor into Saturday morning.
Ceilings will be lower-end MVFR transitioning to IFR, with spotty
drizzle also possible a few hours after stratus moves in. Could be a
brief period of low level wind shear around KHON tonight as surface
winds decrease toward advancing trough, but KFSD and KSUX will
likely keep strong enough surface winds to preclude a consistent

IFR Stratus/drizzle conditions will gradually improve beginning late
Saturday morning, but MVFR ceilings will likely persist over parts
of northwest Iowa and southwest Minnesota beyond this TAF period.




SHORT TERM...Chapman
AVIATION...JH is the U.S. government's official web portal to all federal, state and local government web resources and services.