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FXUS63 KFSD 251731

Area Forecast Discussion
National Weather Service Sioux Falls SD
1131 AM CST Sat Feb 25 2017

.SHORT TERM...(Today and Tonight)
Issued at 338 AM CST Sat Feb 25 2017

Surface ridge over the western forecast area as of 09Z, with mostly 
clear skies to the east and increasing mid level clouds in a zone of 
weak warm advection to the west. The clouds will advance east across 
the forecast area through the day, and could actually help warm the 
areas which received the heavier snow yesterday a bit more than pure 
sunshine. Still should see the coolest temperature across the snow 
cover in our south, with highs today ranging from mid-upper 20s in 
northwest Iowa, to mid 30s around Chamberlain and the Highway 14 

Subtle wave drops into the Dakotas tonight, which will thicken the 
cloud cover and could produce some spotty precip to our north. Layer 
of dry air below 8kft should limit the chance for measurable precip 
this far south. However, a few high-res models indicate potential 
for spotty flurries across our far north. Thicker clouds across the 
north should keep temperatures relatively mild in the lower-mid 20s. 
while southern areas with thinner clouds and fresh snow drop into 
the mid teens.

.LONG TERM...(Sunday through Friday)
Issued at 338 AM CST Sat Feb 25 2017

Kept temperatures relative cool across the snow pack region on 
Sunday, but with fair amount of melting today and then again on 
Sunday am left to wonder how much snow pack will be left around on 
Monday. Left a small shadow in the forecast highs on Monday where 
deepest snow fell. 

Monday night things get trickier as a series of short waves move 
across the area in warm air advection regime.  Model soundings 
suggest a warm nose above the surface, potentially leading to mixed 
precipitation.  Models are showing quite a spread in potential 
precip and type. Am not overly confident in temps aloft and surface 
temperature forecast on Monday night, but went ahead and left mixed 
precipitation mention mainly along and east of highway 60 in 
Northwest Iowa into southwest Minnesota. In strong warm air 
advection, some solutions are suggesting moisture transport may be 
strong enough to keep temperatures at or above freezing, resulting 
in minimal impact.  For now, confidence is not high enough to 
mention in HWO, but will need to keep an eye on this in future 
forecast iterations. 

Cold front moves through the area on Tuesday night with 925 hpa 
temps returning below freezing.  Could be a weak disturbance 
dropping through in northwest flow on Thursday, but looks to be cold 
enough for snow.  Both the GFS and ECMWF hint at a solid warmup on 
Saturday, but looks to be short lived as a cold front Saturday night 
knocks temperatures aloft back to near 0C.


.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1130 AM CST Sat Feb 25 2017

VFR conditions will persist through the evening hours. System
moving through the Upper Plains will bring slightly lower ceilings
though the overnight hours and perhaps a few sprinkles near Huron,
but no large scale impacts to the region. 

Clouds will again thin into Sunday morning. 




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