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FXUS63 KABR 131200 AAA

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
600 AM CST Wed Dec 13 2017

.SHORT TERM...(Today and Tonight)
Issued at 403 AM CST Wed Dec 13 2017

Wind, light mixed precipitation, and falling temperatures will be 
the main concerns this period. The 500mb shortwave over the eastern 
half of the area will quickly exit to our southeast this morning.

Will start out with light rain as temperatures hover in the upper 
30s to mid 40s. Continue to monitor latest trends and update hourly 
forecast for the warm conditions. Expect falling temperatures today, 
behind the exiting sfc low shifting from south central MN to just 
south of Lake Michigan by mid afternoon. This shift will allow winds 
to diminish, with the weakening pressure gradient, but will also 
allow cooler air to surge in. Temperatures will remain nearly steady 
today in the 30s and 40s. Rain initially, may mix with and change 
over to light snow by mid afternoon. If roadways cool down fast 
enough some icing will be possible.

Given the winds gusting 35 to near 50 mph today, very high grassland 
fire danger index values will show up again over Stanley, Jones, and 
Lyman Counties. Relative humidity values will fall around or below 
40 percent southwest of a line from Mobridge to Miller. A weak sfc 
ridge will be overhead around 00z, with winds continuing to slowly 

.LONG TERM...(Thursday through Tuesday)
Issued at 403 AM CST Wed Dec 13 2017

The fairly high amplitude long wave pattern across the conus is 
expected to continue through the long term. However, the pattern is 
showing some signs of shifting its orientation. The west conus mid 
level ridge is expected to retrograde back to the west, thus 
allowing energy to dig strongly south over the Rockies/western highs 
plains by this weekend and early next week. This energy then ejects 
east/ne out across the central plains, with pretty decent areal 
coverage of pcpn. However, for now, the main storm track looks to be 
mainly south of the ABR cwa. Throughout the entire period, the 
highest probabilities for measurable pcpn looks to be Thursday, with 
light snow expected from the Missouri River valley east to the James 
River valley, as a relatively weak system drops south across the 
region. Temperatures, overall, will continue to favor near or above 
normal through the forecast given a lack of any true arctic air 
anywhere near the Northern Plains.


.AVIATION...(For the 12Z TAFS through 12Z Thursday Morning)
Issued at 553 AM CST Wed Dec 13 2017

A batch of mvfr cigs north of the region will continue to slide
south over the area this morning. Isolated snow showers are
possible at KABR/KATY. Strong winds will gradually subside toward
mid to late afternoon.  


SD...Wind Advisory until 3 PM CST /2 PM MST/ this afternoon for 

     Wind Advisory until 3 PM CST this afternoon for SDZ005>008-010-

MN...Wind Advisory until 3 PM CST this afternoon for MNZ039-046.


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