Area Forecast Discussion
Issued by NWS Aberdeen, SD

Home |  Current Version |  Previous Version |  Text Only |  Print | Product List |  Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
755
FXUS63 KABR 101129 AAA
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
629 AM CDT Mon Jun 10 2024

.KEY MESSAGES...

- There is a 40 to 70% chance of showers and thunderstorms late
this afternoon through tonight. Some storms along and west of the
Missouri River may become strong to severe this evening. Main
threats are winds gusting around 60 mph, with hail up to quarter
size.

- There is a 20-40% chance of showers and thunderstorms Wednesday
into Wednesday night, mainly along and east of the James River
Valley. Some storms may become strong to severe.

&&

.SHORT TERM /TODAY THROUGH TUESDAY AFTERNOON/...
Issued at 505 AM CDT Mon Jun 10 2024

A few light showers/sprinkles have popped up across central SD this
morning, but have quickly dissipated as they encounter the sfc high
to the east and lack of instability/forcing. South to southeast
winds will increase today. There are two different model scenarios
for the focus point for this evening`s thunderstorms. One extends a
trailing sfc front down into SD from a low at the Canadian border
with a reinforcing upper trough and its associated PVA. The other
has a Rocky Mountain low moving into the Plains and extending an
inverted sfc trough into central SD. Either solution provides enough
forcing for strong to severe storms. Models start bringing storms
into our west river counties around 0z. Latest RAP only shows 1000
to 2000 J/kg of CAPE right around a narrow corridor near the
inverted sfc trough but strong shear of 40 to 50 kts. Lapse rates
are not that impressive at about 5 to 6. A very concentrated
marginal area seems the most appropriate. Will likely see storms
weaken quickly as they progress east of the Missouri and the best
parameters weaken. Showers and general thunderstorms will spread
east overnight with the upper trough and cold front.

For Tuesday, sfc high pressure builds in again, but the upper trough
will keep temperatures seasonable.

&&

.LONG TERM /TUESDAY EVENING THROUGH SUNDAY/...
Issued at 505 AM CDT Mon Jun 10 2024

The long term portion of the forecast will feature an active weather
pattern with a couple storm systems crossing the region.

The period begins on Tuesday night with an area of low pressure over
the western Dakotas with warm air advection over the eastern
Dakotas. A few storms may develop early Wednesday morning with the
WAA and weak LLJ. The surface low pressure and associated frontal
boundaries will  move eastward on Wednesday, with convection
possible along a cold front over eastern SD and western MN. The
latest rendition of the NBM suggest mostly dry conditions on
Wednesday, with only a 15-20% chance of storms. The thunderstorm
potential increases to 25-40% after 0Z Thursday, which may be too
high based on some deterministic models with the frontal boundary
east of the CWA.

There is some consistency among models with another storm system
crossing the region Wednesday night through Thursday morning with
the NBM showing a 20-40% chance of pcpn. After a brief period of dry
conditions Thursday afternoon through Friday afternoon, a couple of
storm systems will track across the region Father`s Day weekend,
with several rounds of showers and thunderstorms.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 628 AM CDT Mon Jun 10 2024

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are expected to prevail through tonight. Showers
and thunderstorms will move into central SD around 0z this evening
and will likely affect KMBG and KPIR by 3z. Vsby may deteriorate
in stronger storms.

&&

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

$$

SHORT TERM...Wise
LONG TERM...SD
AVIATION...Wise