Area Forecast Discussion
Issued by NWS Sioux Falls, SD

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397
FXUS63 KFSD 172123
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
323 PM CST Fri Feb 17 2017

.SHORT TERM...(This evening through Saturday)
Issued at 323 PM CST Fri Feb 17 2017

The mild weather continues!  Cold front east of I-29 will shift east
with surface high pressure building into the region behind the
front.  This should result in gusty winds rapidly dropping off with
sunset tonight. The clear skies and light winds should allow for
great radiative conditions. 925 hpa temps fall slightly below 10C
behind the front, and with the light winds, will be a bit more of a
challenge to warm on Saturday.  Will still see temperatures 25- 30
degrees above normal climbing into the upper 50s to lower 60s.


.LONG TERM...(Saturday night through Friday)
Issued at 323 PM CST Fri Feb 17 2017

The unseasonably warm conditions will continue into the first half
of the extended forecast, however a big pattern change arrives late
next week.

Well amplified upper level ridge centered over the eastern Plains
will continue to bring very warm conditions to the region. South to
southeast winds become breezy in the afternoon, which will allow low
level moisture to build northward. Clouds will be on the increase,
but despite the filtered sunshine, temperatures will once again be
well above normals in the 60s. Went ahead and nudge slightly towards
the BCCONSRAW for highs to warm the area a few degrees above the
SuperBlend.

With increasing moisture, cloud cover, and southerly
flow continuing into Sunday night, lows will only drop into the
upper 40s to mid 50s, which is as much as 40 degrees above the
normal low for this time of year. Upper level trough arrives in the
western Plains Sunday night. Good lift and forcing swings northeast
through the area late Sunday night into Monday, bringing our next
chance for rain showers. Models also indicate some weak elevated
instability will also arrive late at night into Monday morning, so
will continue with mention of isolated thunderstorms.

The spring-like warmth continues behind the departing system on
Tuesday and Wednesday, with warm zonal flow. Highs will once again
reach the upper 50s to upper 60s.

Focus then turns to a potent system emerging from the Rockies on
Wednesday night or Thursday. The GFS, ECMWF, and GEM all strengthen
the upper low over the Plains on Thursday and Thursday night,
however the location of the low center is markedly different between
each model. The GEM is slowest and furthest south, while the GFS
maintains more of an open wave further north. All models point
towards a high chance for precipitation in our area, but the type is
less certain. Colder air is likely, and right now it looks a good
potential for accumulating snowfall in the region. Not enough
confidence in amounts or location at this time. With strong winds
also likely, it is certainly a system to keep an eye on as it draws
nearer.


&&

.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 1145 AM CST Fri Feb 17 2017

 VFR conditions through the period. Weak cold front will move
through the region this afternoon with surface high pressure
settling into the region tonight. This will result in breezy
westerly winds this afternoon, decreasing with sunset. Light winds
are expected Saturday.


&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
IA...None.
NE...None.
&&

$$

SHORT TERM...BT
LONG TERM...
AVIATION...BT



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