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FXUS63 KABR 132015

Area Forecast Discussion
National Weather Service Aberdeen SD
315 PM CDT Sun Oct 13 2019

.SHORT TERM...(This Evening through Monday Night)
Issued at 314 PM CDT Sun Oct 13 2019

A bit of a tricky forecast setting up tonight as some residual cloud 
cover will be hanging around which will have a play into how far 
temperatures fall overnight. Through the day today, we've seen 
thicker, more widespread cloud cover thinning across East River 
zones in our CWA. Temperatures have been responding faster with more 
sunshine in our western zones as readings have reached the 40s. Most 
of the eastern areas have been stuck in the 30s.

This cloud cover still all part of the large, cyclonic circulation 
from the upper low across southern Ontario. As we move through the 
rest of today and into the overnight, sfc high pressure will slide 
across the forecast area. Our winds should become fairly light 
overnight. Some of these leftover clouds are anticipated to stick 
around tonight from the James Valley and points east. More clearing, 
if not clear skies will be more long lived through the night across 
the Missouri Valley. But, there could be some breaks in the clouds 
in the east as well. A weak waa pattern develop early tomorrow 
morning as well. So, this presents a challenge to tonight's lows. 
Played conservative and hedged between the coldest and warmest 
guidance. In addition to the chilly temps, do think some patchy fog 
will develop toward early morning across the James Valley areas as 
llm remains high with the new/melting snow cover. We begin to turn 
the corner on early winter on Monday as southerly flow kicks in and 
temps begin to moderate. Although highs will still fall below 
normal. A new system and associated cold front enters the picture 
late in this period. However, it looks to remain mostly dry as it 
begins to pass through.

.LONG TERM...(Tuesday through Sunday)
Issued at 314 PM CDT Sun Oct 13 2019

On Tuesday, pretty good pressure gradient is in play and mixing 
layer winds should prove rather blustery. There is some low level 
CAA happening on Tuesday, too, so looking at high temperatures 
Tuesday remaining way below normal, probably in the upper 30s to mid 
40s. There is the potential for some wrap-around (TROWAL-forced) 
light showery-type precipitation Tuesday into Tuesday evening, 
mainly for areas of the CWA north of U.S. Highway 212.

Otherwise, the forecast is dry all the way through the end of the 
week, aided by the building of a large upper level ridge across the 
central CONUS Tuesday night through Thursday. Heights are falling by 
the end of the week into the weekend with steering flow winds aloft 
re-orienting to more of a west-southwesterly direction. It's 
probable that a couple s/w's are working across the region between 
Friday and Sunday. There are some low pops in for Saturday night and 
Sunday, but low confidence right now that there will be much in the 
way of precipitation developing/occurring over this CWA, given the 
amount of ongoing disagreement in deterministic solutions and the 
spread showing up in ensembles output.

It does still look as though deterministic and ensemble solutions 
support a warm up in the low levels that gets started across the 
western half of the CWA on Wednesday and then spreads east across 
the rest of the CWA Thursday, with a warm airmass persisting through 


.AVIATION...(For the 18Z TAFS through 18Z Monday Afternoon)
Issued at 1242 PM CDT Sun Oct 13 2019

Cloud cover will be the tricky part of the forecast at the local
terminals the remainder of today into Monday morning. MVFR cigs
are still hanging on across eastern areas, but satl trends show
break ups in the overcast. A bkn MVFR cig is still probable
through this afternoon at KABR & KATY. Feel more clearing takes
place across the western terminals with time later today and
tonight. Anticipate MVFR cigs to return overnight, especially at
eastern TAF sites.




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