Area Forecast Discussion
Issued by NWS Aberdeen, SD

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FXUS63 KABR 121727

Area Forecast Discussion
National Weather Service Aberdeen SD
1227 PM CDT Thu Oct 12 2017

Issued at 1220 PM CDT Thu Oct 12 2017

Increased winds slightly from previous forecast, especially across
and east of the James River Valley. ATY experienced a peak wind
last hour of 30kts. Pesky high clouds remains an issue fcst model
wise, and will continue to update as needed. The cold front has
shifted just east of a line from MBG to PIR.

UPDATE Issued at 626 AM CDT Thu Oct 12 2017

See updated aviation discussion below.


.SHORT TERM...(Today through Saturday Afternoon)
Issued at 339 AM CDT Thu Oct 12 2017

Breezy southerly winds continue across the eastern CWA as pressure
gradient remains tight ahead of approaching cold front. Low level
jet is also positioned across the eastern CWA. This is keeping temps
up in the 40s for most areas.

For later today, the southerly winds will persist over the eastern
CWA as the cold front approaches. Mild air at 925/850 mb combined
with good mixing will allow temps to climb into the upper 60s and
low 70s for many areas. Increased highs today a few degrees and
sided on the higher end of guidance. Coolest readings will reside
over the northwest CWA where cooler air will first arrive behind the
passing cold front. Frontal passage will be dry as the air mass
remains moisture starved.

Surface high will move into the region tonight with winds going
light for much of the CWA. Lows are a bit tricky tonight because
soundings and guidance all suggest a layer of mid and high clouds
from southern up through eastern SD into western MN overnight into
early Friday morning which will keep temps up just a bit. Although,
indications point to mostly clear skies over north central SD so
have decreased lows there a few degrees as this area is right under
the surface high. This cool high pressure will keep temps on Friday
in the upper 50s to low 60s.

Focus will then shift to Saturday as a surface trough moves across
the area with decent upper level support in the form of a shortwave
trough. The best lift actually resides across northeast/eastern SD
into western MN so have increased POPs just a bit into the likely
category, although rainfall amounts will remain on the light side.

.LONG TERM...(Saturday Evening through Wednesday)
Issued at 339 AM CDT Thu Oct 12 2017

An upper level trough and associated shortwave energy will be
centered over the middle part of the country when the extended
period begins. This trough will push east of the region by Sunday
morning, with northwest flow then setting up until Wednesday, when
the flow becomes southwesterly as a trough develops over the western
part of the country. At the surface, the low that looks to bring
rain to the area Saturday will be over western Wisconsin, with
lingering showers across mainly the eastern part of the area
Saturday night. High pressure then becomes the dominant feature over
the area through the day Tuesday before getting pushed east by an
approaching low pressure trough. The trough only reaches the western
high plains by the end of the period, so anticipate dry conditions
Sunday through Wednesday.

Sunday will be the coolest day of the period, with highs mainly in
the 50s. Will then see a bit of a warming trend, with highs in the
60s Monday through Wednesday. Overnight lows in the 30s will be
common Saturday night and Sunday night, then in the upper 30s to mid
40s Monday night, Tuesday night and Wednesday night.


.AVIATION...(For the 18Z TAFS through 18Z Friday Afternoon)
Issued at 1220 PM CDT Thu Oct 12 2017

VFR ceilings and vis remain as a cold front has shifted just east
of a line from MBG to PIR. Strong winds remain well ahead of the
front, for ABR and ATY, as well as just behind the front as they
switch out of the northwest.




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