Area Forecast Discussion
Issued by NWS Aberdeen, SD

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FXUS63 KABR 252015

Area Forecast Discussion
National Weather Service Aberdeen SD
315 PM CDT Tue Oct 25 2016

.SHORT TERM...(This Evening through Wednesday afternoon)
Issued at 313 PM CDT TUE OCT 25 2016

Forecast challenges in the near term center on precipitation
coverage/timing and amounts.

Currently, under a cloudy sky and breezy southeast winds,
temperatures have climbed anywhere from 5 to 15 degrees today with
readings ranging from the mid 40s across the northeast forecast
zones to the mid 60s across the southwestern forecast zones. Also,
bands of rain and more recently clusters of elevated thunderstorms
are noted marching east-northeastward across the forecast area.

Tonight and Wednesday: the ongoing precipitation event will focus
most of its accumulation across far northeast South Dakota and west
central Minnesota through late this evening before most of the
forcing/lift for appreciable precipitation amounts re-focuses off to
the south and east of this cwa. However, there is still some
potential to see a stratus field develop over some portion of the
cwa overnight and persist into the daytime hours on Wednesday.
Temperatures will be held in check tonight over areas covered by
cloudy skies. If the far western cwa manages to break out of clouds
overnight, ample surface/boundary layer moisture should work to
produce some foggy conditions by morning. Lowest low temperature
readings overnight are right now set in the upper 30s over Corson
county. Further east and south under cloudy skies, 40s for low
temperatures seems more probable. The inverse effect is expected on
Wednesday, where areas under clouds for part/most of the day will
not see much temperature recovery (low to mid 50s at best) while
areas further west are expected to see more sunshine and
temperatures warming into the 60s to perhaps near 70.

.LONG TERM...(Wednesday night through Tuesday)
Issued at 313 PM CDT TUE OCT 25 2016

Not much change overall in mid and long range guidance with a
generally dry pattern of upper ridging. A pair of systems will pass
overhead, however between the deterministic GFS/ECMWF, neither
system seems to provide much for precipitation potential as best
forcing ends up outside the CWA. They will have more impact on
temperatures and winds however as 850mb temperatures warm to +2
standard deviations above climo late Thursday into early Friday.
With a 10mb pressure gradient across the state, and pressure falls
of 4-6mb/6hrs, surface winds will remain breezy Thursday night.
Despite weakening, a shift from south to southwest and then
northwest will allow for favorable mixing conditions Friday. Cloud
cover may have an impact on the temperature forecast but as it
stands forecast highs/lows Thursday/Friday already appear to be
about 20F above climo. Deterministic models share a general trend in
timing of the thermal advection pattern with Mondays system, so
anticipate there will be another surge in abnormally mild air Sunday
night/Monday morning.


.AVIATION...(For the 18Z TAFS through 18Z Wednesday Afternoon)
Issued at 1148 AM CDT TUE OCT 25 2016

Areas of rain are starting to fill in on radar across the forecast
area, but none of it is directly over a terminal yet, except
perhaps at KABR where light rain returns appear to be filling in
just southwest of the terminal moving east-northeast. Still
appears as though the chances for rain at KMBG and KPIR will only
last a few more hours, while the likelihood of rain
developing/moving over the KABR and KATY terminals will continue
to increase into this evening before diminishing later tonight.

Stratus clouds have been slow to develop this morning, although
cig/vis plots and mvfr/ifr satellite enhancement suggests there is
a slug of fog/low clouds slowly lifting/expanding northward out of
Nebraska into south central South Dakota, so it is still entirely
possible that periods of MVFR/IFR conditions will develop at some
point during the TAF valid period (especially KABR/KATY).
Wherever the western edge of low clouds ends up being later
tonight, could see some fog development (possibly KMBG/KPIR).




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