963
FXUS63 KABR 301130 AAA
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
630 AM CDT Sun Jun 30 2024

.KEY MESSAGES...

- Southeast winds will gust up to 45 mph west of the Missouri River
  this afternoon.

- There is a Marginal Risk (level 1 out of 5) of severe weather late
  tonight into Monday along and west of the Missouri River. The main
  threats will be large hail and strong wind gusts.

- Monday afternoon and evening, the region will be in a Slight Risk
  (level 2 out of 5) of severe weather. This time period looks to be
  the next best chance for organized severe storms. Predictability on
  details is still low, but no threats (wind, hail, tornado) are ruled
  out at this point.

- The active weather pattern of showers and thunderstorms persists
  through the workweek.

&&

.UPDATE...
Issued at 628 AM CDT Sun Jun 30 2024

See updated aviation discussion below.

&&

.SHORT TERM /TODAY THROUGH MONDAY AFTERNOON/...
Issued at 314 AM CDT Sun Jun 30 2024

Upper level ridging will build over the central part of the country
today and tonight before a more southwesterly flow develops on Monday
ahead of an approaching trough. Will see some decent shortwave
energy ride up the east side of the ridge and across the area
during the day Monday.

At the surface, high pressure currently over the region will get
pushed east today as low pressure slides across the Rockies. A
tightened pressure gradient will develop this afternoon between
these two systems, which will allow for increasing southeasterly
winds (20 to 35 mph). Areas west of the Missouri River may see gusts
exceed 45 mph. The gradient remains somewhat tight tonight as well
as the low reaches the western Dakotas by Monday morning. Therefore,
expect breezy conditions (15 to 30 mph) to continue tonight. The
low, and its associated frontal boundary, will track across the area
on Monday and will be the focus for shower and thunderstorm
development. Windy conditions (20 to 35 mph) will continue as well,
with the stronger winds translating to the central and eastern parts
of the CWA. There is potential for a few strong to severe storms to
develop during the afternoon hours, mainly along and west of the
Missouri River where better instability (1500-2500 J/kg) and shear
(35 to 50 knots) develop.

High temperatures today will be in the 70s. Low temperatures tonight
will be in the upper 50s to lower 60s. Highs on Monday will range
from the upper 60s across the Sisseton Hills region to the lower 80s
along and west of the Missouri River.

&&

.LONG TERM /MONDAY EVENING THROUGH SATURDAY/...
Issued at 314 AM CDT Sun Jun 30 2024

Monday evening a low pressure system will be making its way across
the region, with both a warm front and a cold front draped across
the area. This will be the focus area for some possibly severe
storms that could last into Tuesday morning. This trough remains in
place into Wednesday morning when we transition to a short lived
ridge. Thursday a low starts to down from Canada. Models have moved
this up about 24 hours. Tracks are also much more similar than
previous model runs, moving the low southeast across ND towards the
ND/SD/MN border by very early Friday morning. The low continues to
move east through the day Friday. Still in an upper level trough
pattern, some shortwaves move through Saturday and Sunday.

Monday evening some storms, possibly severe, are expected to be
impacting the area. SPC has highlighted SD in a slight (2 of 5) risk
for severe weather with all hazards possible. The next chance for
some precipitation will start early Thursday morning as 30 to 60%
PoPs move eastward across the forecast area. Thursday`s peak will be
in the evening with 70 to 80% north of Hwy 14 and east of Hwy 281.
On the thunderstorm parameter side of things, mid level lapse rates
look to be around 7 to 7.5 during the afternoon with MUCAPE values
between 500 and 1200 J/kg across the area. Bulk shear is highest
where the lapse rates and CAPE are highest (in eastern SD) at around
35 to 45 kts. There is also a surface boundary moving west to east
across SD, reaching eastern SD during the afternoon hours. Storms
could fire off this surface boundary, and a few may become severe.
There is a slight chance (15 to 25%) of rain on Sunday with the
stronger of the two weekend shortwaves.

Temperatures through the period will bounce between around average
and about 10 degrees below average as stay in more of a cold air
advection pattern. Winds are still expected to remain around normal
through the period.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 628 AM CDT Sun Jun 30 2024

Terminals KABR,KATY,KPIR,KMBG

VFR conditions will prevail across the area today and tonight.
There may be a few thunderstorms west of the Missouri River late
tonight.

&&

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

$$

SHORT TERM...Parkin
LONG TERM...KK
AVIATION...Parkin