FXUS63 KABR 191728 AAC

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
1228 PM CDT Tue Jun 19 2018

Issued at 1015 AM CDT Tue Jun 19 2018

With some thinness in the broken/ovc skies, and temperatures not
too far off some highs, have bumped up temperatures a notch here
and there. Really not looking like much in the way of pcpn until
this evening and overnight, and mainly over western and southern
South Dakota.


.SHORT TERM...(Today and Tonight)
Issued at 431 AM CDT Tue Jun 19 2018

Forecast challenges include temperatures and forecasting
timing/coverage of weak convection by late this afternoon through

Currently, temperatures are ranging from the 50s to the 60s under a
cloudy sky. Winds are light from the north and light showers of rain
are continuing to try and hold on across the far eastern forecast
zones (mainly the I-29 corridor eastward into MN).

Guidance this morning seems to have latched on to the cloudy skies
around and implies a mostly cloudy sky should persist for much of
the CWA for much of the day. Remnant showers this morning should be
dissipated or shifted out out of this CWA by mid to late morning.
The temperature forecast will be a tricky one today if the clouds
stick around all day. For now, sticking with the idea that despite
the cool northeasterly boundary layer mixing wind and cloudy
conditions, there could still be as much as a 10 to perhaps 15
degree diurnal. It is almost the Summer Solstice, after all.

Much of the GSM output and CAM solutions has really backed away from
seeming much in the way of showers or storms across the western or
southwestern forecast zones. Perhaps something is trying to work
into central or south central South Dakota by late this evening, or
during the late night hours. Precipitation forecast confidence is
rather low at the moment without a clearly discernible shortwave
lined up, upstream, to work into the region today/tonight.

.LONG TERM...(Wednesday through Monday)
Issued at 431 AM CDT Tue Jun 19 2018

Upper level low pressure will slowly move east across the northern
plains Wednesday through Wednesday night, with the best precip
chances remaining across the southern half of SD. Models continue to
suggest this as southern SD remains in the area of best synoptic
scale lift as this system moves through. Areas further north are
also fighting drier air, so don't expect much of anything over
northern portions of the CWA. Instability looks to be lacking over
the southern CWA, so expecting mainly showers with just a few
embedded thundershowers perhaps. POPs remain rather high for
Wednesday over the southwest CWA, then taper off towards Thursday
morning as the system continues to slide east-southeast.

Thursday into Friday appear dry for most of the area as a surface
ridge slides through the area. Although, more shortwave energy moves
into the region this weekend with a return to precipitation chances.
Did not make many changes to inherited POP grids at this point.

As for temperatures, they appear to be near average throughout the
period - give or take a few degrees. Given lower level thermal progs
that models are showing, it appears highs will range from the mid
70s to mid 80s throughout the period, with no signs of abnormally
hot air moving into the region.


.AVIATION...(For the 18Z TAFS through 18Z Wednesday Afternoon)
Issued at 1226 PM CDT Tue Jun 19 2018

Mostly VFR skies/vsbys can be expected. However, KPIR may see some
lower cigs/rain tonight.




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