Area Forecast Discussion
Issued by NWS Aberdeen, SD

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FXUS63 KABR 212325 AAA
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
625 PM CDT THU JUL 21 2016

.UPDATE...
Issued at 623 PM CDT THU JUL 21 2016

See updated aviation discussion below.


&&

.SHORT TERM...(This Evening through Saturday Night)
Issued at 256 PM CDT THU JUL 21 2016

Forecast challenge remains temps and pcpn chances for the early part
of the weekend.  For tnt front will remain splayed out generally
just to the southeast of the CWA. There really hasn`t been much ll
dry air advection today and thus dewpoints have remained quite high.
The higher dewpoints have contributed to low convective inhibition
around and north of the frontal boundary.  Still feel that warm
temps aloft will probably cap most convection.  However, an isolated
late aftn or evening storm is still possible. For now have decided
to keep out mention given such low pops.

For Friday most of the day should be dry although isolated storms
from overnight activity may sneak into the far western CWA early.
Most of the activity should wait until late aftn or evening as
return flow starts ushering in higher dewpoints and weak energy
aloft transitions into the area. Not sure how far any MCS Friday
night will work east given that the focus of the LLJ looks to be
mostly over North Dakota.

On Saturday upper trof begins ejecting toward south central Canada,
with a trailing cold front heading east over the CWA. Expect
convection to re-ignite along boundary as it pushes into and east
of the James Valley Saturday afternoon. Certainly can`t rule out a
few severe storms with this activity given the progged cape/shear.

Temperatures will start the weekend off hot, but then trend toward
normal as mid level heights crash under eastward moving upper
wave.


.LONG TERM...(Sunday through Thursday)
Issued at 256 PM CDT THU JUL 21 2016

The 500MB low over southern Manitoba at daybreak Sunday will extend
a trough across ND and northern SD Sunday afternoon-evening. The
last of the showers will be off to our east as the sfc low exits
into western Ontario and high pressure builds in from the west.
Sunday looks to be the coolest day over the next week, with highs
ranging from the low 80s over MN to around 90 southwest of Pierre.
850MB temps will briefly fall to 14-18C Sunday afternoon. It will
be short lived though.

On Monday, the rebounding 500MB ridge will slide across the Northern
Plains. This will be while the sfc high, overhead at 12Z Monday,
exits across MN and IA. Southerly winds will make a return Monday-
Monday night. There looks to be some timing/strength differences
with the next 500MB trough sliding from ID Sunday evening to the
Dakotas Monday night-Tuesday morning. After the 500MB trough exits
to the east, northwest to zonal flow will linger through Thursday.

Will continue to run with a model consensus from Monday night on,
due to the low confidence. After starting out with dry weather Sunday-
Monday morning, it will be difficult to completely rule out some
showers/thunderstorms west Monday afternoon, and across the rest of
the area Tuesday night-Thursday.


&&

.AVIATION...(For the 00Z TAFS through 00Z Friday Evening)
Issued at 623 PM CDT THU JUL 21 2016

VFR conditions will prevail across the area tonight and through
the day Friday.

&&


.ABR Watches/Warnings/Advisories...
SD...Excessive Heat Warning until 8 PM CDT /7 PM MDT/ this evening for
     SDZ006>011-015>017-021.

     Excessive Heat Warning until 7 PM CDT /6 PM MDT/ Friday for
     SDZ018>020-022-023-033>037-045-048-051.

MN...Excessive Heat Warning until 8 PM CDT this evening for MNZ039-046.

&&

$$

SHORT TERM...TDK
LONG TERM...KF
AVIATION...Parkin



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