Area Forecast Discussion
Issued by NWS Kansas City/Pleasant Hill, MO

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539
FXUS63 KEAX 300221
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
618 PM CDT Tue Oct 29 2024

.KEY MESSAGES...

- Gusty winds 40-50 MPH continue through today and likely into the
  overnight

- Showers and thunderstorms move through tomorrow afternoon and evening.
  Some strong to severe storms with all hazards possible.
  Damaging winds are the primary hazard, but hail and a couple
  tornadoes are possible.

- Uncertainty of strong to severe storms remains as the high
  shear relatively low CAPE environment adds uncertainty
  ranging from several severe storms possible to none.

- Long term outlook appears more active and wet with a potential for
  excessive cumulative rainfall over the coming days.

&&

.DISCUSSION...

Issued at 240 PM CDT Tue Oct 29 2024

A stout high to the east and a digging trough to the west is
creating compressing the pressure gradient across the central CONUS.
Solar heating mixes fast moving upper level winds down to the
surface resulting in wind gusts around 40-50 MPH across the region.
A Wind Advisory remains in effect through 7 AM Wednesday; however,
observations will tell if the lower level jet is able to decouple
during the overnight which may curtail gusts until sunrise where
gusts accelerate again around 30-40 MPH ahead of the arrival of a
cold front.

The cold front associated with this western trough pushes more
aggressively eastward tomorrow. This acts as a rather brute force
lifting mechanism to the conditionally unstable air. Warm air and
moisture advection this afternoon partially destabilizes with lapse
rates hanging around 7 C/km, meaning that any influx of
moisture or temperature could push stability one way or the
other. This makes the outlook over the next 36 hours somewhat
uncertain. Forecast guidance has been pretty consistent on a
high shear, relatively low CAPE environment with the front
being the primary driving force. This adds confidence in the
chances for precipitation; however, it also adds uncertainty on
the magnitude and severity of potential storms. While high shear
does help maintain thunderstorms that form, it may also be so
much that it shears them apart before they have a chance to
really organize. Depending on what side of stability the
environment lands on could really determine the magnitude of
storms. Again, confidence is high that we will see precipitation
tomorrow. It is just a matter of the strength of storms and
timing. The primary uncertainty of storm magnitude lies south of
the MO/IA border with higher chances for strong to severe
storms even further south across E and SE KS. Far eastern KS and
western MO remain a little more nebulous. Recent RAP analysis
has increased the available CAPE for the region around 1000-1500
J/kg which is more than enough for facilitate strong to severe
storms. Earlier most ensemble members where outputting CAPE
values around 500-1000 J/kg, which is still enough to get
isolated strong to severe storms.

Precipitation is expected to develop fairly quickly along the front
likely west of the CWA. This could open up the possibility of
multicell interactions where updrafts and anvil debris may
interfere with each other limiting the overall strength of
storms. That said the overall linear storm mode, CAPE and DCAPE
nearing 1000 J/kg, and the likelihood for some descending rear
inflow along the line points toward enhanced chances for severe
wind. Elevated bulk shear and helicity values present some
opportunity for tornadoes; however, hodographs, while somewhat
curved, are relatively stretched; so the potential looks low and
limited temporally. One inch hail also is possible with the
slight increase in CAPE. Overall, these high shear, marginal
CAPE scenarios present a significant challenge as minor
alterations in atmospheric variables can lead to potentially
expansive severe weather or none at all. Timing continues to
trend more slowly with storms entering the region mid afternoon
and remaining into the overnight.

Cooler conditions come behind the front for Halloween night. Highs
Thursday reside in the upper 50s with evening temperatures sinking
to the low 50s. Overnight lows dip back into the upper 30s. As
seemingly typical for this time of year, the temperature pattern
appears sinusoidal fluctuating between above and below normal.
The extended forecast looks much more active for the coming days
with multiple waves bringing opportunities for precipitation.
In fact, the concerns may shift from being too dry to getting
too wet too quickly with long range precipitation outlooks
trending above normal and PWAT values suggesting opportunities
for concentrated areas of heavy rainfall.

&&

.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 617 PM CDT Tue Oct 29 2024

VFR conditions prevail through the overnight hours with breezy
conditions persisting. Southerly wind gusts over 30 knots on
occasion will be possible tonight. There are subtle hints of
MVFR ceilings developing during the morning hours tomorrow,
though certainty is low at this time. Gusty conditions will
continue throughout the daylight hours, with bursts over 35
knots expected due to diurnal mixing. Ceilings are forecast to
lower tomorrow afternoon (20-21Z) with showers and storms
traversing the terminals from the west during said timeframe.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...Wind Advisory until 7 AM CDT Wednesday for MOZ001>008-011>017-
     020>025-028>032-037>039-043-044-053.
KS...Wind Advisory until 7 AM CDT Wednesday for KSZ025-057-060-
     102>105.

&&

$$

DISCUSSION...Pesel
AVIATION...Hayes