766
FXUS63 KEAX 022023
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
323 PM CDT Tue Sep 2 2025

.KEY MESSAGES...

* Quiet and cool tonight with some patchy ground fog possible.

* Showers/storms, a few severe possible, Wednesday late afternoon
  and evening as a cold front moves through from the N.
  - Large hail and damaging winds main storm risks

* Much below normal temperatures by Thursday and through the weekend
  as another/reinforcing cold front moves through Friday
  - As much as 10 to 15 degrees below normal
  - Lows into the 40s possible, mainly Thurs and Sat mornings

&&

.DISCUSSION...
Issued at 320 PM CDT Tue Sep 2 2025

Morning showers across northern Missouri tied to a weak 850mb
boundary generally subsided quickly this morning. Giving way to
quiet conditions. The exception being an area of weak/weakening
showers moving out of NE Kansas/NW Missouri in conjunction with weak
shortwave, seen best on mid-level water vapor imagery. This is to
say, much ado about nothing today with regards to sensible weather.
Otherwise clearing skies with budding fair weather cu this
afternoon. Highs remain on track for upper 70s to low 80s as many
locations are within a couple degrees as of 3pm LT. Tonight, surface
high influence tends to dominate as its center glides S/SE through
central/eastern Kansas. Clearing skies and light winds will allow
efficient nocturnal cooling, dropping lows into the mid-upper 50s
for most. Widespread fog appears unlikely with lack of moisture
above the near/immediate surface, even with the strong/steep low
level inversion. Instead, suspect some areas of ground fog,
especially in river valleys and locations prone for cold air
pooling.

Wednesday remains the day for a well advertised cold front to
traverse the region, as well as a risk for a few strong to severe
storms. A highly amplified mid-level/500mb pattern will remain and
be reinforced as a potent/deepening closed low drops out of the
Canadian Plains and into the Great Lakes region. Associated surface
low ahead of this feature will drift NE while trailing cold front
drops into/through the northern and central Plains. Timing of
frontal arrival has not seen too much change among synoptic and now
available CAM/high-res guidance, suggesting crossing into northern
Missouri late morning/lunch hour. Likely ongoing shower/thunderstorm
activity will cross over into north-central to northeast Missouri,
associated with fringes of deeper synoptic scale lift. This activity
not expected to pose any risk as it will be elevated and within a
weakly unstable (<500 J/kg) MUCAPE environment as it drifts SE
through the morning and into the afternoon. Moving westward, a
tricky precip/PoP forecast for portions of NW/W into central
Missouri. Guidance has broadly come into agreement of prevailing
westerly surface flow as surface high drifts south, limiting any
appreciable moisture return. Frontal passage/convergence may be a
bit weaker in this areas as well, and as a result CAM guidance tends
to be on the quieter side initially for areas north of the KC Metro
and west of Highway 63. Just to the west, into Kansas, southerly
surface winds yields both better moisture return and strong
convergence along the front. Hi-res/CAM guidance depicts
SB/MLCAPE values >1500 J/kg from roughly I-49 westward.
Soundings/wind profiles too show some potential veering near-
surface winds, helping boost low-level hodograph curvature
within an environment of >40kt 0-6km bulk shear. This suggests
an environment that may be supportive of a couple/few organized
supercells. Damaging winds and large hail remain primary risks
with deep inverted V profiles and freezing levels around to less
than 10kft. Upscale growth likely limited initially with storm
motions tending to move off the front (SE motions), but may tend
to fill in through the evening, which would begin to
limit/depress the severe risk aside from loss of peak heating.
Strong/severe storm risk timing appears best from 5-10pm. Heavy
rain/flooding threat is low as well with the progressive frontal
passage pushing activity southward. SPC Day 1 Outlook
highlights Slight Risk from south of Highway 36 and west of
Highway 65, and lines up with local thinking at this point in
time.

Behind this front is an anomalously cold airmass, as seen in just
about any guidance metric. Euro and GEFS Ensemble SA tables depict
low to mid-level temperatures at the 1 to 2.5 percentiles and
surface temps 10 to 15 deg F below normal. This pushes Thursday
morning lows into the mid 40s to low 50s and highs in the 70s. The
anomalously cool temperatures continue to round out the week and
into the weekend as a reinforcing cold front slides through Friday
as a surface low and mid-level shortwave round the larger mid-upper
level Ontario low. While a dry air mass will be in place, synoptic
guidance continues to suggest this secondary frontal passage may
squeeze out a few inconsequential showers. Overall, this keeps highs
and lows broadly 10 to 15 degrees below normal through the weekend;
primarily in the 70s and mid 40s to low 50s respectively. Gradual
warming returns next week as large scale patterns shifts from cool
northwesterly to more zonal and return of southerly surface winds.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1234 PM CDT Tue Sep 2 2025

VFR conditions expected to prevail across the TAF sites, ahead
of showers and thunderstorms in the periods immediately outside
of this issuance (through 18z Wed). In the immediate term,
scattered, weakening light rain/showers continue to glide SE out
of NE Kansas/NW Missouri. Currently in the vicinity of KSTJ,
this activity has struggled to produce much to the ground with
bases >6-7kft and expectation for weakening trend to continue
as it approaches the KC Metro sites. Thus, have kept all sites,
including KSTJ dry. Otherwise, light/variable winds into this
evening before westerly winds establish themselves late in the
TAF period.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...None.
KS...None.

&&

$$

DISCUSSION...Curtis
AVIATION...Curtis