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000
FXUS63 KABR 122323 AAA
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
623 PM CDT Wed Aug 12 2020

.UPDATE...
Issued at 622 PM CDT Wed Aug 12 2020

Forecast is on track this evening. No major changes are planned.

&&

.SHORT TERM...(This Evening through Thursday Night)
Issued at 352 PM CDT Wed Aug 12 2020

Forecast challenges include temperatures and precipitation chances
Thursday and Thursday night.

Currently, it`s partly to mostly sunny over the CWA, with
temperatures in the 70s and 80s east of the Missouri River valley.
Throughout and west of the Missouri River valley, temperatures are
warming through the 80s and 90s. There is also a lee-of-the-Black
Hills surface trof hanging out over the region, extending from the
Black Hills east toward Huron and southeast toward Sioux City, Iowa.

There appears to be a small window of time this evening, when one or
two thunderstorms could develop on the nose of a low level jet
forecast to form over the CWA this evening and spread north/east
through the region overnight. Low/mid-level thermal advection and
low level moisture advection is continuing across central/south
central SoDak this evening where the nose of the developing low
level jet is forecast to be. Although, by late this evening, the
atmosphere, aloft, may be too warm to support convective
development. Even if a storm could get going, deep-layer shear is
progged at less than 20knots. So, other than a pulse-threat for
perhaps some hail, severe weather potential tonight is rather
limited.

Otherwise, the forecast appears to be a dry one until Thursday
afternoon/night when a boundary begins to move into the CWA. Plenty
of instability around and better deep-layer shear along/behind the
boundary. Some GSM output and hi-res CAM output supports a few
thunderstorms trying to go up right on the boundary Thursday
afternoon/evening while the mid-level thermal capping inversion is
slowly eroded by falling heights aloft as the large western NOAM
upper trof approaches the region. If convection develops on this
boundary, mainly the eastern half/third of the CWA would potentially
be impacted for a few hours. A second/separate round of potential
convection could be approaching/working into the western CWA late in
the Thursday night period. A stronger shortwave/upper jet streak may
be supporting the development or furtherance of convection out over
the northern high plains along or on the northern fringe of a
surface low progged to be edging into the western Dakotas by early
Friday morning. The nose of a low level jet is progged to be over
the CWA late Thursday night as well.

Operational model thermal progs and ensembles 850hpa standardized
anomalies support temperature tonight through Thursday night
remaining above normal.

.LONG TERM...(Friday through Wednesday)
Issued at 352 PM CDT Wed Aug 12 2020

The extended period begins with an upper level shortwave trough
sliding across the area Friday into Friday night. A surface front
will also be moving through, with fairly warm and moist air being
pulled northward ahead of it. This combination of factors looks to
allow for the front to become the focus for thunderstorm development
Friday afternoon and evening, mainly across the eastern part of the
CWA. The one hindering factor may be a bit of a cap, with H7 temps
of +11 to +13 C across the far east during the afternoon hours. SPC
has highlighted the eastern CWA with a marginal to slight risk for
now. Conditions then look fairly quiet for the Saturday through
Tuesday time frame as the upper level flow remains out of the
northwest, but with little in the way of shortwave energy moving
through and with surface high pressure dominating. The high exits to
the east Tuesday night, with some models hinting at the potential
for a few showers or storms on Wednesday.

High temperatures will be in the 80s everywhere Friday, Saturday and
Sunday, then will range from the mid to upper 70s east, to the mid
to upper 80s west Monday, Tuesday and Wednesday. Overnight lows will
be in the mid 50s to lower 60s through the period.

&&

.AVIATION...(For the 00Z TAFS through 00Z Thursday Evening)
Issued at 622 PM CDT Wed Aug 12 2020

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are expected through the period. Winds will become
breezy out of the south on Thursday.

&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
&&

$$

UPDATE...Wise
SHORT TERM...Dorn
LONG TERM...Parkin
AVIATION...Wise