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fxus63 kabr 181739 aac 

Area forecast discussion...updated
National Weather Service Aberdeen South Dakota
1139 am CST Mon Nov 18 2019

issued at 1134 am CST Mon Nov 18 2019

Aviation discussion updated below for the 18z tafs.

Update issued at 1033 am CST Mon Nov 18 2019

Continuing to monitor the system sliding southeast across the
Dakotas. Coverage of showers is more widespread than previous
forecast conveyed, so have been increasing pops and areal coverage
of showers throughout the morning. Looks like most areas across
northern/northeast South Dakota and into west central Minnesota will see showers
today, with a gradual ending from west to east during the
afternoon. Amounts will be light - under a quarter inch. As for
temperatures, will see mild temps in the 50s and low 60s from the
James Valley and points west. Have increased highs a few degrees
over the southwest County Warning Area where best mixing and sunshine will be
found, along with mild temps aloft. Low 60s look like a good bet
there as temps are already in the mid 50s. Highs are a bit more
tricky under the areas that will see increased cloud cover and
precip today, but by this afternoon when better mixing develops
and warmer air moves in, we should see additional temp rises. As
for winds, we are seeing conditions getting close to advisory
criteria west of the Missouri. Conditions should stay marginal
during the day, but will continue to monitor.

Update issued at 523 am CST Mon Nov 18 2019

See updated aviation discussion below.


Short term...(today through Tuesday afternoon)
issued at 325 am CST Mon Nov 18 2019

Low pressure over Saskatchewan is extending a trough across the
western North Dakota to near the Missouri River in SD, and central
NE. Near this boundary, scattered rain showers remain. The eastward
progression would bring the trough to eastern South Dakota and along the South Dakota/Minnesota
border by 18z. Assisted by an shortwave, expect a resurgence of rain
over ND by mid afternoon to slide into far northeastern South Dakota by 21z
and slowly exit into Minnesota shortly after 00z Tuesday. The pressure
gradient will be on the increase through the early afternoon hours
(basically 17-21z), with northwest winds of 20-25kts with gusts 25
to near 35kts west of the James River Valley. The strongest winds
should be west of the Missouri River, where 850mb winds hover near
45kts. Expect clouds to move into the far western counties tonight,
and linger over the northeast along with cooler 850mb temperatures
near 0c. Clearing across the central cwa should result in upper 20s
to near 30 degrees, with low 30s elsewhere. A brief surface ridge
will slide across the area Tuesday morning to early afternoon, with
dry weather continuing, as a ridge of high pressure also builds in

Long term...(tuesday evening through sunday)
issued at 325 am CST Mon Nov 18 2019

The main challenge in the long term period will be the potential for
precipitation early in the period. A low pressure system will be
over The Rockies Tuesday evening, with the southern portion of the
low intensifying Tuesday night, then sliding over the Central Plains
on Wednesday, then to the Great Lakes by midday Thursday. An initial
area of precipitation looks to remain north of the area Tuesday
night into the day Wednesday, but cannot rule out a slight southward
shift, which may bring some precipitation to the northern County Warning Area. Will
see a better chance for precipitation Wednesday night into early
Thursday as the low slides across Nebraska and Iowa. Precipitation
type continues to be tricky. Soundings indicate a fairly dry layer
aloft and a warm layer just about the surface across the northwest
late Tuesday night into Wednesday morning, allowing for the
potential for some freezing drizzle. Will also see a time period
from late Wednesday afternoon into the evening across the eastern
County Warning Area where another warm layer develops above the surface, with not
much of a dry layer aloft indicated. Therefore, may see more of a
potential for freezing rain during this time. Otherwise, rain or
snow will be the main types, but little in the way of significant
accumulation is expected as we will be on the far northern fringe of
the precipitation shield. The remainder of the extended period looks
dry at this time, with high pressure sliding across the area
Thursday and Friday, followed by a dry trough passage over the

High temperatures will be in the 30s Wednesday and Thursday, with
slightly warmer air returning, with highs in the upper 30s to upper
40s Friday, Saturday and Sunday. After a mild night with lows in the
upper 20s to lower 30s Tuesday night, lows will be mainly in the
upper teens and 20s through the remainder of the period.


Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 1134 am CST Mon Nov 18 2019

Kabr and Katy will see -shra/rain showers through the afternoon hours,
with periodic MVFR visibility in rain showers. Overall, cigs appear to stay in
VFR, although Katy may see a brief period of MVFR cigs late this
afternoon into early evening. Otherwise, across kpir and kmbg, VFR
conditions will prevail with gusty west-northwest surface winds
during the afternoon hours.


Abr watches/warnings/advisories...
South Dakota...Wind Advisory until 5 PM CST /4 PM MST/ this afternoon for



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