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FXUS63 KABR 181127

Area Forecast Discussion
National Weather Service Aberdeen SD
627 AM CDT Fri Aug 18 2017

.SHORT TERM...(Today through Sunday Afternoon)
Issued at 415 AM CDT Fri Aug 18 2017

Continue to see isolated showers and storms across the CWA while a 
larger coverage of precipitation is noted across ND closer to the 
main vort max. Have been adjusting POPs the past couple hours to 
account for radar trends. Actually had a mini heat burst here in 
Aberdeen about an hour or so ago with an area of showers that moved 

For later today, will be watching fairly compact vort max / 
shortwave as it drops southeast across the area. Low center moves 
right across far northeast SD and west central MN. Fairly decent 
coverage of showers and storms across ND right now with this system 
and it's all moving southeast. CAM solutions show decent areal 
coverage across the far northeast CWA today, so have increased POPs 
accordingly. There is about 1000 J/KG MLCAPE to work with, but no 
shear. Mid-level lapse rates are fairly healthy. Interesting to note 
that some of the parameters associated with landspouts or very weak 
tornadoes are showing up on the low end. Given the nice vort moving 
through and associated surface boundaries / wind shift, one cannot 
completely rule this out. May mention this in the HWO.

Conditions quiet down tonight as surface high pressure quickly 
passes through the area. By Saturday morning, this high is already 
departing to the southeast, thus allowing for southerly winds and 
much warmer air to move into the region. Still fairly good signals 
for nice warming on Saturday, and will see highs in the 80s and 90s. 
Fairly dry air will be moving into central SD as well, with RH 
values dropping into the 20s and 30s. Does not appear to hit Red 
Flag criteria though. Cool front will then drop south through the 
area Saturday night, but looks to come through mostly dry. Slightly 
cooler temperatures can be expected on Sunday.

.LONG TERM...(Sunday Evening through Thursday)
Issued at 415 AM CDT Fri Aug 18 2017

Will start out with zonal flow aloft, with a subtle wave embedded 
within this flow moving across the region. At the surface we will 
have a lee low to the west, with a stalled front across the South 
Dakota/Nebraska state line, and low level easterlies. A low level 
jet will set up over Nebraska/southeast South Dakota Sunday 
night/early Monday morning resulting in elevated convection. There 
is a second shortwave embedded within zonal flow aloft, and the 
current timing brings its influence into the area Monday night. 
Models again show the stalled front becoming the focus for 
convection, though without the low level jet influence this time. 
Tuesday - during the day - aloft we see a shift to a northwest flow 
regime and dry conditions as surface high pressure moves from Canada 
- into the Western Lakes region - and continues southeast through 
the end of the work week. 

Temperatures should trend right around average for this time of 


.AVIATION...(For the 12Z TAFS through 12Z Saturday Morning)
Issued at 626 AM CDT Fri Aug 18 2017

Generally VFR for all terminals. We could see some convection
enter into the KABR/KATY areas, but confidence is too low to
include in the TAFs at this time.



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