654
FXUS63 KEAX 281138
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
638 AM CDT Sat Jun 28 2025

...12z Aviation Update...

.KEY MESSAGES...

* Hot and humid conditions continue through Sunday.
  - Heat Index values mainly mid 90s to around 100 deg F

* Today: A few scattered showers and non-severe thunderstorms
  possible, mainly south of I-70, and best chances toward southern
  Missouri.

* Overnight Tonight into Sunday: Additional shower and non-
  severe thunderstorm chances spreading northward into central
  and northern Missouri.

* Sunday Evening and Overnight: More widespread thunderstorms
  anticipated, including potential for a few strong to severe.
  Damaging winds to be the primary threat.

* Early to Mid Work Week: A bit cooler and less humid.

&&

.DISCUSSION...
Issued at 403 AM CDT Sat Jun 28 2025

Little change to the large scale pattern of late with continued weak
and mostly zonal flow aloft regionally and only a couple low
amplitude shortwaves traversing the US-Canada border. While one of
those low amplitude waves did allow for a weak surface boundary to
cross into northern Missouri yesterday, its remnants are already
indistinguishable within surface obs/surface analysis. As a result,
the hot/humid/stagnant air mass remains expected to be in place
through much of the weekend. Expect highs to remain in the upper 80s
to low 90s in most locations along with low to mid 70s dew points
pushing heat index values toward the upper 90s and even low 100s in
some cases.

In addition to the hot/humid conditions continuing, a few chances
for showers/storms too will be seen through the weekend. The first
of which may manifest this morning as LLJ induced convection works
out of NE Oklahoma/SE Kansas and into portions of SW Missouri.
Majority of hi-res/CAM guidance keeps this activity on the southern
fringes of the CWA with weak steering flow angled to the NE/ENE. Any
activity that does get into the southern CWA this morning to be of
the generic thunderstorm variety, but may fester much of the morning
and into the afternoon with already weak capping further eroding
with even modest diurnal heating. By the afternoon today, there may
be an opportunity for a few scattered storms within the CWA,
potentially as far north as the Highway 36 corridor, with hi-res/CAM
guidance generally depicting an very weakly capped to uncapped
environment and approaching the convective temperature. Most
guidance depictions keep convection at bay, but have brought low
(<20%) PoPs toward the I-70 corridor to help signal the possibility.
Any air mass storms/convection that does occur will largely be short
lived within a poor shear environment and of little to no
consequence aside from brief locally heavy rainfall and non-severe
wind gusts.

Tonight/overnight will see better chances for showers/storms within
the CWA in response to a modest 25-30 kt SW oriented LLJ nosing into
SW Missouri. The environment conditions of late will continue to
prevail at this time, meaning weak shear and modest elevated CAPE
values resulting in scattered to widespread non-severe thunderstorm
activity. PWats do climb back toward 2 inches, and could yield some
localized heavy rain concern with the more widespread convective
potential, but HREF and extended RAP/HRRR runs remain largely
scattered in nature and do not suggest a great potential for
concerning rainfall amounts. This activity may persist through the
morning and into the afternoon before subsiding.

By Sunday evening, the stagnant large scale pattern begins to see
more substantial disruption as a shortwave trough moves off the
Canadian Rockies and deepens modestly over the Northern Plains.
While surface low development is predominantly not expected, surface
high development on the backside of wave too push a cool frontal
boundary across the area Sunday night and overnight. Ahead of this
boundary, very strong to extreme instability is depicted among
guidance and is bolstered with HREF and NBM mean values >2500-3000
J/kg and 75 percentile values approaching and exceeding 3500-4000
J/kg. Fortunately, weak shear profiles largely limit any
organization and prolonged severe potential, but the extreme
instability potential alone warrants at least some concern for
sporadic severe potential. Freezing levels around or greater than
14kft should further limit severe hail potential, leaving damaging
winds as the leading candidate. Strong/severe threat should be most
prominent over NW areas of Missouri with frontal timing currently
anticipated to enter the state during the evening/dusk hours. PWats
>2 inches and deep warm cloud layer depths will yield efficient
heavy rain potential too, but progressive nature of convection is
expected to limit any flooding concerns. Both the strong/severe
potential and heavy rain threats are too seen within SPC and
WPC ERO Marginal Risks.

Behind the frontal passage, the hot/humid conditions of late will
see modest relief through at least the first half of the work week.
Expect temperatures to ease back a few degrees into the mid 80s, and
dew points to fall back toward the low to mid 60s. Mid-late work
week then sees southerly flow return with temperatures and dew
points rising back into the lower 90s and upper 60s to low 70s
respectively.

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 635 AM CDT Sat Jun 28 2025

Majority of TAF period will be highlighted by quiet, VFR
conditions with S/SSW winds to around 10kts. There is a very low
potential for a widely scattered storm or two this afternoon,
but given the low probability do not have any mentions at this
time. Late in the period, scattered TSRA is anticipated to
blossom over portions of the area as a modest low level jet
noses into the area, primarily affecting the metro TAF sites
KMCI/KMKC/KIXD. Given the scattered nature and some lingering
uncertainty on coverage, have opted for PROB30s with this
issuance/at this time.

&&

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

&&

$$

DISCUSSION...Curtis
AVIATION...Curtis