299
FXUS63 KABR 171133 AAA
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
633 AM CDT Tue Jun 17 2025

.KEY MESSAGES...

- There is a 20 to 50 percent chance of showers and thunderstorms
  across the forecast area today into this evening, especially for
  areas along and south of U.S. Highway 212.

- There is a Marginal risk (level 1 out of 5) for severe
  thunderstorms Thursday night.

- Temperatures heating up into the 90s on Friday and Saturday are
  possible. These readings are 10 to 20 degrees above normal.
  South of U.S. Highway 212, there is a 30 to 60 percent chance
  temperatures could climb to or above 100F degrees.

&&

.UPDATE...
Issued at 630 AM CDT Tue Jun 17 2025

See below for an aviation forecast discussion for the 12Z TAFs.

&&

.DISCUSSION...
Issued at 331 AM CDT Tue Jun 17 2025

At 3 AM CDT, showers supported by an MCV are working through the
western forecast area. Better upper jet support now through the
end of today, than previous days, lends credibility to either
ongoing or redeveloping showers/storms this morning/afternoon as
this MCV marches across the CWA. Temperatures are in the 50s and
60s this morning and winds are variable, generally less than 10
mph.

Today is the day that shortwave energy strong enough to register a
small divot in the 500hpa height fields in the models will be
working across the region. Should see some modest mid-level WAA
recovery later today into this evening while shortwave UVV and upper
jet support to result in, at least, scattered coverage of
showers/storms. Considerably less instability/deep layer shear
today/tonight still looks the part, so at this point, expecting
primarily "general thunderstorms" over the region.

Surface high pressure and upper level height rises take over heading
into Wednesday, persisting into Thursday. So, dry weather conditions
are forecast for said forecast periods. Return flow sets up (and
potentially a low level jet) Thursday night, so night-time thunder
could be possible. In fact, heading into the Friday through Sunday
timeframe, while an upper level ridge of high pressure is over the
region, mid-level temps may end up being warm enough that any
precipitation chances over the weekend would be night-time chances
whenever/where-ever a low level jet forms. Models are still
resolving frontal boundary timing issues Sunday/Monday. This looks
like another strong fropa as temps are expected to transition from
highs in the 90s to low 100s out ahead of the boundary to highs in
the 70s to around 80F degrees behind the boundary.

Still dealing with the problem of actual ensemble system-powered
forecast high temperatures for Friday and Saturday being too
conservative this far out in time, with maximum temp values in the
mid-80s to mid-90s. Until all the various ensemble systems` inputs
begin to agree on Friday/Saturday temperatures, can expect this
conservative/cooler forecast high temperatures theme will probably
persist. There is still a 30-50 percent chance on Friday and a 40-60
percent chance on Saturday of high temperatures exceeding 99F
degrees south of U.S. Highway 212 in the CWA.

&&

.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 630 AM CDT Tue Jun 17 2025

Terminals KABR,KATY,KPIR,KMBG

Fog, mostly shallow ground fog, has materialized this morning
(prior to sunrise) at KATY and KABR, knocking visibility down to
MVFR/IFR. Expecting VFR conditions to make a full recovery at
these two terminals within the next couple of hours, joining KPIR
and KMBG in prevailing VFR conditions through the rest of the TAF
valid period. KPIR has the highest probability/chance (~35-50%) of
experiencing a shower or weak thunderstorm later this afternoon
into the early evening hours.

&&

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

$$

UPDATE...10
DISCUSSION...10
AVIATION...10