Areal Flood Warning 8, NWS Aberdeen, SD

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
626 PM CDT Mon Aug 30 2021

.UPDATE...
Issued at 622 PM CDT Mon Aug 30 2021

Continuing to monitor the ongoing storms near the north central
SD border this evening. Also keeping an eye on any chances for
storms farther south as the llj develops later this evening. For
now, the forecast remains on track with no major changes planned.

&&

.SHORT TERM...(This Evening through Tuesday Night)
Issued at 218 PM CDT Mon Aug 30 2021

Current flat westerly flow aloft will give way to rising heights as
we head toward mid-week. For tonight, s/w over MT will continue to
advect into and across ND. Thus, WAA pattern will continue with
moderate LLJ up through the central part of SD. Increasing heat and
instability this afternoon will lead to a chance for convection this
evening and overnight, especially west of the James valley. Given
moderate MLCAPE/moderate deep layer shear and steep mid-level lapse
rates, a few severe storms look possible. Unfortunately, the CAMS
are offering various solutions as to the evolution of convection
this evening over the Missouri valley. Thus, PoP confidence isn't
particularly high over this region. Also, during the evening an H5
speed max enters the western border area of NE/SD. This energy may
well lead to an MCS that starts over southern SD, and then cruises
southeast overnight into NE/IA. There is fair agreement among the
CAMS that this will occur, thus leading to higher forecaster
confidence. At this point Tuesday and Tuesday night appear dry as
mid-level ridge builds over the forecast area. Temperatures over the
short range will favor near average for the time of year.

.LONG TERM...(Wednesday through Monday)
Issued at 218 PM CDT Mon Aug 30 2021

The main challenge in this period continues to be storm chances
going into late Wednesday through Thursday. An upper ridge is
expected to still be overhead as we begin on Wednesday. This should
give most of our CWA a dry but warm and humid day. An upper trough
will be digging into the Pac NW during the day. Shortwave trough
energy is progged to ride up the backside of the upper ridge
northeastward into our region by the end of the day. At the sfc, lee
side troughing will be working into the western Dakotas during the
daytime. Sfc Td's are expected to be pushing into the upper 60s to
around 70 degrees by afternoon. With instability increasing by late
in the day, potential for low-level jet development and a resultant
warm-air advection pattern should lead to a good chance for showers
and thunderstorms going into Wednesday night and Thursday. One
limiting factor that will have to be watched could be the strength
of a developing cap over portions of the region. A cold front is
progged to push through the region by the end of the day Thursday
going into Friday. Most of the area should be drier on Friday, but
additional weaker waves moving through the region this upcoming
weekend could lead to additional chances for more shower activity.

&&

.AVIATION...(For the 00Z TAFS through 00Z Tuesday Evening)
Issued at 622 PM CDT Mon Aug 30 2021

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are expected through the period except in the
vicinity of any thunderstorms. Coverage is still uncertain enough
that any mention of VCTS was left out of tafs.

&&

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

UPDATE...Wise
SHORT TERM...TDK
LONG TERM...Vipond
AVIATION...Wise

Hazardous Weather Outlook...UPDATED
National Weather Service Aberdeen SD
302 PM CDT Mon Aug 30 2021

MNZ039-046-SDZ006>008-011-018>023-312015-
Traverse-Big Stone-Brown-Marshall-Roberts-Day-Spink-Clark-Codington-
Grant-Hamlin-Deuel-
302 PM CDT Mon Aug 30 2021

This Hazardous Weather Outlook is for west central Minnesota and
northeast South Dakota.

.DAY ONE...This afternoon and tonight.

Showers and thunderstorms are possible tonight, severe weather is
not expected.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

Good chances of thunderstorms are expected Wednesday night into
Thursday night.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

SDZ003>005-009-010-015>017-033>037-045-048-051-312015-
Corson-Campbell-McPherson-Walworth-Edmunds-Dewey-Potter-Faulk-
Stanley-Sully-Hughes-Hyde-Hand-Jones-Lyman-Buffalo-
302 PM CDT Mon Aug 30 2021 /202 PM MDT Mon Aug 30 2021/

This Hazardous Weather Outlook is for central South Dakota and
north central South Dakota.

.DAY ONE...This afternoon and tonight.

Scattered thunderstorms are expected this afternoon and tonight.
There is a slight risk of severe weather with large hail and damaging
winds.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

Good chances of thunderstorms are expected Wednesday night into
Thursday night.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be requested. Weather spotters are encouraged
to submit reports to the National Weather Service in Aberdeen. The
public can submit reports on our web page, Facebook page, or our
Twitter feed.