Area Forecast Discussion
Issued by NWS Aberdeen, SD

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FXUS63 KABR 230838

Area Forecast Discussion
National Weather Service Aberdeen SD
338 AM CDT Thu Mar 23 2017

.SHORT TERM...(Today through Saturday Afternoon)
Issued at 336 AM CDT Thu Mar 23 2017

Showers moving up across western South Dakota this morning
associated with the formation of an inverted trough ahead of a weak
shortwave ejecting out ahead of the main upper low. To our east, a
low level jet is gradually sliding into Minnesota. As the day
progresses, NAM BUFKIT profiles support increasing saturation and
possibly drizzle type soundings across much of the CWA, though with
less thickness as you get closer to central and southwest counties.
Steep lapse rates aloft could also support weak elevated convection
on top of this layer.

As the system evolves, a band of precipitation will set up mainly to
the south and winds will be predominantly out of the northeast. Thus
through the middle of the weekend we will see temperatures with a
limited diurnal range. Any breaks of sunshine should get us into the
40 to 50 degree range with 850mb temperatures around +4C.

.LONG TERM...(Saturday Evening through Wednesday)
Issued at 336 AM CDT Thu Mar 23 2017

The period opens with weak surface high pressure in place across the
region, and plenty of surface/bl moisture. Weak upper level ridging
holds for the first couple of days in the extended and by Sunday
night there is very little in the way of a surface pressure pattern
at all. With light winds and plentiful boundary layer moisture
around, will have to monitor skycover trends over the weekend into
early next week for night-time fog potential. The Fog Tool yielded
some light fog potential each night from Saturday night through
Monday night. Beyond Monday night, the current model progs continue
to produce a gradual flow pattern shift to south-southwesterly flow
aloft by the middle of next week and draw an upper level system into
the region within it. Will have to continue to monitor this trend to
see if it holds, as this scenario would bring some precipitation
(rain) chances back into the forecast.

As the dayshift yesterday indicated, there isn`t much in the way of
low level thermal advection in the out periods. Airmass moderation
almost seems more appropriate. Current 00Z suite of GSM low level
thermal progs and ensemble mean output continues to suggest
temperatures in the out periods will be near to slightly above climo
normal at the end of March.


.AVIATION...(For the 06Z TAFS through 06Z Thursday Night)
Issued at 110 AM CDT Thu Mar 23 2017

VFR conditions will prevail across the area overnight. Look for
MVFR cigs to overspread the CWA Thursday morning, along with some
periods of drizzle or light rain by the afternoon and evening.




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