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718
FXUS63 KABR 242017
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
317 PM CDT Tue Sep 24 2024

.KEY MESSAGES...

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- Above normal temperatures return Wednesday through the
  weekend with highs mainly in the 80s, with Thursday seeing
  the warmest temperatures(80s to low 90s).

- Areas around the James River Valley and west will likely
  see strong wind gusts (around 35 mph) Thursday morning into
  the afternoon.
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&&

.SHORT TERM /THIS EVENING THROUGH WEDNESDAY NIGHT/...
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Issued at 317 PM CDT Tue Sep 24 2024

A rather quiet and uneventful weather pattern will be the main theme
in the short range as high pressure will be the dominant weather
maker the next couple of days. This afternoon, we are observing
north to northwest breezes as temperatures warm into the 70s to
around 80 degrees. Fair wx CU has developed this afternoon across
most of the forecast area. These clouds will be mostly gone by early
this evening. This will leave clear skies across the area tonight as
a sfc high pressure system builds in. Low temperatures tonight will
not be as cool as they were earlier in the week with overnight
readings in the upper 40s to low 50s.

Upper ridging builds in overnight and during the day on Wednesday.
Sfc high pressure will gradually begin to shift into our eastern
zones and farther downstream. This will promote winds to turn
southerly during the day. The gradient does begin to tighten in the
afternoon, especially across western SD as sfc low pressure trough
shifts into the Northern High Plains. This will lead to some gusty
southerly winds on the order of about 25 mph or so across our
western zones in central SD during the afternoon. It appears that
sfc dew point temperatures remain in check and high enough during
the afternoon across our western zones that it will mitigate and
concerns for elevated fire conditions. Temperatures will begin to
respond to the southerly low level flow as a warmer air mass in
drawn northward. Wednesday highs will reach the upper 70s to mid 80s
from the James Valley and points east. Mid to upper 80s will be more
common west of the James Valley through West River zones.
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&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
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Issued at 317 PM CDT Tue Sep 24 2024

Overall, the extended period still looks to be rather quiet, with
the main highlights being warmer than average temperatures, along
with dry conditions prevailing. Upper level pattern generally shows
a cutoff low across the south-central/southeastern CONUS, that
eventually ingests the tropical system in the Gulf. Although, it
appears the Northern Plains will not see much in the way of impacts
regarding precip/temperatures as this entire low stays off to the
east/southeast. Will continue to monitor trends though.

Otherwise, conditions look to stay warm, especially early on in the
extended period with highs remaining in the 80s for many areas Thurs-
Sun. Central SD may see low 90s on Thursday as the latest iteration
of NBM highs have increased slightly for that day. These highs
remain above average (about 10 to 20 degrees) for this time of year.
On Thursday, southerly winds look to be fairly strong as the
pressure gradient tightens between a surface high over the Great
Lakes, and an approaching surface trough from the west. Inherited
NBM wind speeds are below advisory levels (30mph sustained, gusts
45mph), and EC EFI values don`t really show evidence of a high
likelihood advisory event either. That said, the combination of wind
and lowering RH to less than 30 percent (perhaps closer to 20
percent) will bring an elevated fire danger to central SD. Although,
it appears the window of lowest RH does not line up with the highest
wind gusts expected on Thursday, as winds actually decrease across
central SD by afternoon as the surface trough moves overhead.
Certainly trends to watch as we get closer to Thursday.

As mentioned earlier, the forecast looks mostly dry through the
period with above average temperatures. It`s not until potentially
Monday and Tuesday when temperatures cool back down to near normal
again as models (deterministic/ensembles) show some cooler air in
northwest flow (with a cold front passage) moving over the Northern
Plains. Of course, still some timing issues on the front passage.
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&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1241 PM CDT Tue Sep 24 2024

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are expected to persist at all 4 terminals the
next 24 hours.

&&

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

$$

SHORT TERM...Vipond
LONG TERM...TMT
AVIATION...Vipond