903
FXUS63 KEAX 120527
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1227 AM CDT Mon Aug 12 2024

...Updated 06z Aviation...

.KEY MESSAGES...

- Showers and thunderstorms will become increasingly likely with
time tonight.  Some storms may be capable of producing locally heavy
rainfall tonight into Monday morning.

- More active pattern is expected this upcoming week with a
  series of disturbances moving through the region leading to
  scattered chances of thunderstorms as temperatures return
  closer to seasonal averages.

&&

.DISCUSSION...
Issued at 338 PM CDT Sun Aug 11 2024

On the large scale, upper level low pressure over the Hudson Bay
continues to weaken and push east with relatively fast mid-upper
level flow across the northern US. Short wave over the Dakotas has
lead to the development of convection. This convection should
attempt to work east-south east ahead of the wave, but scant
instability will limit progression of storms.

Broad warm air advection on the east side of the upper level ridge
across the western US has lead to temperatures warming into the
upper 70s to lower 80s across the region.  Southerly winds has lead
to an increase in precipitable water, which will accelerate tonight
as low level jet forms across the central plains.  This increase in
low level moisture will aid in the destabilization of the
atmosphere, though most unstable CAPE values are largely expected to
remain below 500 J/kg. With strong speed shear in the mid and upper
levels of the atmosphere, the instability is the limiting component
for a more robust severe weather event. Precipitable water values
are expected to approach 2", allowing storms to be very efficient
rain producers.

Storms are expected to develop tonight ahead of the short wave
moving from the Dakotas- Iowa- western Illinois. Increasing moisture
and shear could lead to isolated/scattered storms developing in the
evening hours, but more organized activity should hold off towards
06Z Monday immediately ahead/south of the approaching short wave.
Storms should be fairly efficient rain producers, but given the
relatively dry antecedent conditions and the progressive nature of
the storms, am not expecting flooding concerns outside of training.

On Monday, precipitation is expected to shift east, but can`t
entirely rule out some redevelopment tomorrow afternoon across
central-eastern Missouri mainly along and east of the highway 63
corridor. In areas where clouds are able to at least partially
clear, should see warmer muggier conditions develop with high
temperatures warming into the 80s.

Additional showers and thunderstorms are possible on the nose of the
low level jet both Tuesday and Wednesday morning.  The latest
guidance suggests the focus Tuesday morning may be farther south
across the southern plains, but Wednesday morning is more likely to
see additional storms across north/central Missouri. Additional
sporadic chances of storms continue into late week as upper level
ridge tries to expand but continues to be held in check with a
series of short waves moving across the upper level ridge.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1224 AM CDT Mon Aug 12 2024

First round of showers is moving eastward, more development is
expected heading into the overnight hours. Ceilings will
gradually drop to IFR by the early morning hours of Monday. Most
precipitation activity should between 12z-14z. There is still
moderate amounts of uncertainty with thunderstorm trends and
timing through the overnight hours.

&&

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

&&

$$

DISCUSSION...BT
AVIATION...Krull