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346
FXUS63 KABR 132013
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
313 PM CDT Thu Jun 13 2024

.KEY MESSAGES...

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- A more active weather pattern sets up beginning Friday
  afternoon, and will continue into at the least the first half of
  next week. This will bring multiple opportunities for showers
  and thunderstorms to the region (30-60% chance). The greatest
  chance for severe weather will be on Monday along and east of
  the James River Valley.
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&&

.SHORT TERM /THIS EVENING THROUGH FRIDAY NIGHT/...
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Issued at 312 PM CDT Thu Jun 13 2024

Upper level ridging will build over the region tonight and through
the morning hours on Friday. The flow will become more zonal Friday
afternoon as a shortwave trough crosses the Rockies. The trough will
be strongest south of the region, with just the far southern part of
the CWA getting clipped by some energy Friday night.

At the surface, high pressure will be the dominant feature over the
area tonight and Friday morning, keeping conditions dry. The high
will then get pushed to the east, with the region becoming situated
between it and low pressure to the west Friday afternoon. Southerly
flow will increase across central South Dakota and will bring
increased moisture to the area. Precipitation chances will also
increase, first across central South Dakota Friday afternoon, then
across the entire area Friday night ahead of the low pressure
system, which will reach western South Dakota by late Friday night.
Severe chances look pretty minimal, but may be a bit more elevated
across the southwestern CWA Friday evening closer to the
aforementioned shortwave energy, and where 1000-1500 J/kg of MUCAPE
and 45 knots of bulk shear look to develop.

Low temperatures tonight will be in the lower to mid 50s. High
temperatures on Friday will be in the upper 70s to mid 80s. Lows
Friday night will be in the lower to mid 60s.
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&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
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Issued at 312 PM CDT Thu Jun 13 2024

The upper flow pattern will continue to remain active through most
of this period with multiple waves or disturbances moving through
the region, each giving us a chance for showers and thunderstorms.
The first in a series of waves will be upon us at the start of the
period on Saturday. Ensemble clusters show an upper level trough
will be positioned across the western CONUS and PacNW. With a
shortwave ridge shifting east of our region by the start of the
weekend, southwesterly flow aloft will become the predominant
pattern across the Northern Plains and Upper Midwest.

Sfc low pressure and associated frontal boundary is progged to be
located off to our west on Saturday, across parts of the western
Dakotas and Northern High Plains. Southerly low level flow increases
through the day with increasing humidity and temperatures.
Instability does increase ahead of the boundary later in the day on
Saturday but we also anticipate the potential for capping as warm
air floods in at the mid levels. Deep layer shear isn`t all too
impressive(20-25kts) ahead of the boundary across our area. Better
chances for severe potential will be across parts of western ND and
southeastern SD by Saturday night. The focus for strong to severe
storms across southeast SD will be the result of a better shortwave
lifting northeast out of NE into IA and MN Saturday into Saturday
night. Precip chances are higher in our east as a result where there
is potential for some heavy rain. Portions of northeast SD(east of
the James Valley) into west central MN have a 15-35% chance for
seeing a 0.5" of rain in a 24 hr period ending by late Saturday
night.

The frontal boundary is poised to shift eastward and through the CWA
late Saturday into Sunday and then begin to stall out to our east
and/or slowly lift back to the north and west early next week.
Sunday still looks to be the drier day of the two for the upcoming
weekend before the next shot of moisture and potential for strong to
severe storms return Monday. Another disturbance in that series is
expected to shift through the region on Monday. Sfc low pressure
will slide along that aforementioned stalled front across parts of
eastern SD/western MN and be the focus for showers and storms. With
a southwesterly mid level jet along with a moist and unstable
environment in place, ingredients will be in place for convection,
perhaps strong to severe. We also me be dealing with some capping
issues though too for some areas of the CWA, at least earlier on in
the daytime hours. That could change by days end with a better
chance for severe convection kicking off Monday night into Tuesday.
SPC continues to highlight our eastern forecast area with the Day 5
15% severe risk and that seems to be reasonable at this time. Timing
and placement differences among guidance continue to lend to lower
confidence in how this severe event will eventually play out.

The pattern really remains fairly consistent Tuesday through
Thursday next week. An upper trough across the PacNW is progged to
shift eastward across the Northern Rockies with continued multiple
disturbance riding through the flow across our region. This will
give us continued off and on chances for showers and thunderstorms
through the end of the period. Overall, temperatures through the
period will remain seasonal if not above normal at times with highs
generally in the upper 70s and 80s and overnight lows in the mid 50s
to mid 60s.
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&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1224 PM CDT Thu Jun 13 2024

Terminals KABR,KATY,KPIR,KMBG

VFR conditions will prevail across the area through the TAF
period. Northwest winds will gust to around 20 knots across the
eastern part of the region this afternoon. Light and variable
winds will occur during the nighttime hours and across the east
Friday morning. Winds will become southeasterly across central
South Dakota Friday morning, and will increase into the 15 to 25
knot range.


&&

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

$$

SHORT TERM...Parkin
LONG TERM...Vipond
AVIATION...Parkin