748
FXUS63 KABR 151528 AAB
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
1028 AM CDT Wed May 15 2024

.KEY MESSAGES...

- Showers and thunderstorms will occur today along a frontal boundary
  tracking across the region. Areas east of the James River Valley
  will see the highest amounts of rainfall, in excess of one half
  inch in some locations.

- Above average temperatures can be expected on Friday with highs in
  the in 80s. Temps in the low 90s could be possible.

- A frontal boundary crossing the area late Friday afternoon and
  through the overnight hours will produce a 20 to 60 percent chance
  for thunderstorms.

&&

.UPDATE...
Issued at 1024 AM CDT Wed May 15 2024

Mid-level shortwave trough and surface boundary are over the
region this morning, continuing to provide areas of rainfall. As
the day progresses, this system slowly pushes east and should see
an end to the rainfall from west to east into the evening hours.
Made some minor adjustments to PoPs/sky to match recent radar and
satellite trends.

&&

.SHORT TERM /TODAY THROUGH THURSDAY AFTERNOON/...
Issued at 313 AM CDT Wed May 15 2024

An upper level shortwave trough will track across the Northern Plains
today and this evening, exiting to the east late tonight. Will see a
brief period of northwest flow overnight before another trough
tracks across the area on Thursday.

At the surface, a frontal boundary currently over the central CWA
will continue to track eastward this morning before it stalls out
over the far eastern CWA this afternoon. This front will be the
focus for precipitation, with mainly rain showers expected. Cannot
rule out a few thunderstorms as there will be some shear along the
front, but instability will be minimal, so no severe weather is
expected. With the front stalling out, will see a more prolonged
period of rain, mainly east of the James River Valley. Some
locations may see in excess of one half inch of rainfall today. The
front exits to the east this evening, with mainly dry conditions
expected tonight as weak high pressure moves in. The high will get
pushed east on Thursday as another low pressure system approaches
from the northwest. A few of the models are hinting at some light
rain making it to north central South Dakota Thursday afternoon, but
most of the CAMs are not showing this, so will keep the entire area
dry on Thursday.

High temperatures today will be in the 60s. Low temperatures tonight
will be in the mid to upper 40s. Highs on Thursday will be in the
70s.

&&

.LONG TERM /THURSDAY EVENING THROUGH TUESDAY/...
Issued at 313 AM CDT Wed May 15 2024

The long term portion of the forecast begins on Thursday night with
perhaps a weak storm system passing across North Dakota with a low,
under 20 percent chance for pcpn across this CWA. Models have
trended drier Thursday night through most of Friday, with most of
the CWA seeing dry conditions.

On Friday, an area of low pressure over the western Dakotas will
bring much above average temperatures into the CWA, with 925 mb
temps reaching the mid 20C. These temps are above the 90th
percentile, and a few degrees near daily max 925 mb temp. 850 mb
temps are also expected to reach the 90th percentile. Analogs
support highs reaching the 80s, to perhaps the low 90s on Friday.
These warm temperatures will not last as the low pressure system and
associated cold front will cross the CWA Friday evening and
overnight, bringing a 30 to 60 percent chance for showers and
thunderstorms. Excellent deep layer shear, along with modest
instability, some storms Friday evening could become strong to
severe. The severe potential could be limited due a capping inversion
along and ahead of the frontal boundary, with convection possibly
remaining post-frontal. The front pushes east into MN by Saturday
morning with the trough over the region, bringing cooler
temperatures on Saturday.

The weather pattern remains active Sunday into early next week with
periods of showers and thunderstorms possible. Confidence is low
with timing and rainfall potential, thus pops are more of a broad
brush approach.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 623 AM CDT Wed May 15 2024

Terminals KABR,KATY,KPIR,KMBG

Scattered rain showers, along with a few thunderstorms, will occur
across the area today. The rain will become more widespread across
northeastern South Dakota and west central Minnesota later this
morning and this afternoon as a frontal boundary stalls out over
that region. MVFR cigs will settle in over central South Dakota
this morning, then will spread eastward this afternoon. Cigs will
improve to VFR levels from west to east tonight, but the MVFR cigs
will likely remain over the far eastern part of the through the
end of the TAF period.


&&

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

$$

UPDATE...TMT
SHORT TERM...Parkin
LONG TERM...SD
AVIATION...Parkin