008
FXUS63 KABR 192007
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
307 PM CDT Sat Oct 19 2024

.KEY MESSAGES...

- Well above normal temperatures will return through at least
  Tuesday, highest Sunday and Monday when temperatures will be
  in the 70s to around 80 (20 to 25 degrees above normal).

- There is a 15 to 20 percent chance of light rain Monday
  afternoon over portions of central South Dakota, and Monday
  evening over far northeastern South Dakota into west central
  Minnesota.

- Light rain chances (20 to 40 percent) Tuesday night through
  Wednesday morning, with the highest chances over south central
  South Dakota. The probability of rainfall over 0.1 inches
  remains less than 20 percent Monday through the midweek.

&&

.SHORT TERM /THIS EVENING THROUGH SUNDAY NIGHT/...
Issued at 306 PM CDT Sat Oct 19 2024

The region will be under upper level zonal flow tonight through
Sunday morning, then will see more of a ridge set up ahead of an
approaching trough Sunday afternoon and Sunday night.

At the surface, the region will be situated between high pressure to
the east and a low pressure trough digging down the lee of the
Rockies tonight and Sunday. Southwesterly flow will usher warmer air
back into the area on Sunday, with much above (15 to 20 degrees)
normal temperatures returning. The low to the west will track across
western South Dakota Sunday night, with the front associated with it
just reaching the far western part of the CWA by early Monday
morning. No precipitation is expected during the near term period.

Low temperatures tonight will be in the 40s. High temperatures on
Sunday will be in the 70s. Lows Sunday night will range from the mid
40s across north central South Dakota, to the mid 50s across
northeastern South Dakota and west central Minnesota.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
Issued at 306 PM CDT Sat Oct 19 2024

Clusters are all in agreement on a split flow pattern consisting of
a ridge sprawled across Canada and a mid level low/trough over
Colorado, by 12Z Monday. This system will push northeast and over
the Central Plains Monday evening, which will turn our mid level
winds southerly as the system continues its track eastward and over
~IA/MO by 12Z Tuesday. At the same time, this ridge in Canada will
shift eastward as a couple of shortwaves (one moving in off the
Pacific Coast and one from northern Canada) will phase together over
the central parts of the territories Tuesday. There is a little bit
of a difference between the ensembles on the intensity and placement
of the trough and how far south it will stretch at this time.
Tuesday through Wednesday the trough will continue east as a ridge
builds over the western CONUS. Again, differences on how fast this
trough exits along with amplitude of the ridge and its axis`
position. End of next week a troughing pattern sets up over the
Pacific/western Conus as the ridge moves east, but very low
confidence on the exact outcome as models are inconsistent with
timing and intensity of the overall pattern.

Clusters do show the potential for some light moisture over our
southern CWA Monday afternoon/evening with this area being on the
northern extent of the low. EC seems to bring this chance a bit more
north with GEFS/GEPS keeping any precip chances clipping or just
south of the CWA. Latest NBM has backed off due to this with a 15-
20% chance pops over central to south central SD. With the trough
over Canada and its low, GEFS indicates possible moisture over parts
of northern/northeastern CWA late Monday night into Tuesday morning
with EC keeping it further north and just brushing the ND/SD border.
NBM cuts back on pops as well with only a 15-20% chance over our far
northeastern CWA late Monday into early Tuesday. A cold front is
forecasted to swing southeastward through the CWA Tuesday with the
models indicating the CWA behind the cold front by ~Tuesday
afternoon. ENS/GEPS show post frontal/shortwave precip whereas GEFS
keeps it dry Tuesday night into Wednesday. As of now NBM has
broadbrushed a 20-40% chance of pops over the CWA, highest pops over
central SD to start, with the precip shifting eastward with the
system through Wednesday morning. Probability of QPF> 0.10" looks to
be minimal at 15% or less as on now Monday through the midweek. High
pressure then moves in behind it for the midweek, centered over the
Northern Plains, before pushing southeast on Thursday with dry
conditions during this time.

Temps look to run an impressive 20 to 25 degrees above average for
Monday with southwesterly flow at 850 and south winds at surface.
With diurnal mixing, forecasted highs range in the 70s to around 80.
EC EFI ranges from 0.7 to spots of 0.9 east of the Mo River, with a
shift of tails of zero. NBM 25-75th spread is only 3 to 4 degrees,
leading to higher confidence. Tuesday will still run about 10-15
degrees above average but really depends on the speed of the cold
front. Right now highs range in the 60s to lower 70s. NBM spread is
4-7 degrees, highest over central SD in regards to the frontal
passage/timing. Around average temps return for one day on Wednesday
with the high overhead. With the ridge building, temps look to warm
back up about 10-15 degrees above average for the end of the week.
However due to model variability the NBM spread for temps is 9-17
degrees for the end of the week, highest over central SD.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1224 PM CDT Sat Oct 19 2024

Terminals KABR,KATY,KPIR,KMBG

An area of MVFR stratus over the far eastern part of the area will
gradually diminish during the early afternoon hours. Otherwise,
VFR conditions will prevail through the TAF period.


&&

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

$$

SHORT TERM...Parkin
LONG TERM...MMM
AVIATION...Parkin