632
FXUS63 KEAX 301052
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
552 AM CDT Tue Apr 30 2024

.KEY MESSAGES...

- Severe storms possible this evening into tonight, damaging
  winds and large hail the main threats...a isolated tornado can
  not be ruled out.

- Additional rounds of storms expected Wednesday evening
  through Thursday. Some of these storms may be strong to severe
  Wednesday night.

- Several rounds of rainfall on top of already saturated soil
  will make flash flooding and additional river flooding a
  concern.

&&

.DISCUSSION...
Issued at 227 AM CDT Tue Apr 30 2024

Another period of active weather looks to begin late today into
tonight. High pressure over the area early this morning will quickly
slide southeast of the area with WAA getting underway by late
morning. The strong WAA will aid in driving highs into the upper 70s
to lower 80s today. It will also help to pump moisture back into the
area with dewpoint rising into the upper 50s to lower 60s this
evening. Late this afternoon into the evening a mid-level will move
from the northern Plains into the Upper Midwest. This will forecast
a cold front into the area with storms developing out ahead of it.
These storms will have the potential to be severe as they will be
moving into an environment of moderate/strong instability of 2000-
2500J/Kg of MUCAPE. Effective shear will be around 40-45kts. Given
these parameters, severe weather with damaging winds and large hail
being the main threats. The tornado threat appears low at this time
mainly due to weaker 0/1Km shear and veered surface winds. Heavy
rain will also be possible with PWATs in the 1.25"-1.50" range
however, the system should be progressive enough today to mitigate
anything more than very localized flooding. The front is expected to
sag south of the area overnight and will remain there for most of
the day on Wednesday. A easterly fetch at the surface will cool
conditions a bit with highs in the 70s. Also, on Wednesday a upper
level trough will dig through the northern Rockies. As we get into
late in the day Wednesday into Wednesday evening, a series of lead
shortwave look to eject out ahead of the main trough into the local
area. The surface boundary that was south of the forecast area will
begin to lift slowly north into the southern CWA as a LLJ develops
and nose into the area. With, several shortwaves, a nearly
stationary boundary and a LLJ providing lift and pumping moisture
into the area, on top of recent wet antecedent conditions flooding
becomes a major concern particularly Wednesday night into Thursday.
PWATs will remain between 1.25"-1.50" through the period. Late
Thursday, the upper level trough finally pushes through the northern
Plains into the Upper Midwest and puts enough of a push on the cold
front to finally shift it south and east of the area. All told 1-3"
of rain is expected with locally higher amounts possible.

A brief respite from the rain is expected as surface high pressure
moves into the area for Thursday night into Friday. Highs Friday
will be in the low to mid 70s. However, as we get into Friday night
another trough will move from the central Rockies through the
central/northern Plains forcing a cold front into the area. This
will allow another round of thunderstorms and heavy rain to develop
over the area. Storms are expected to last through Saturday morning
when before the front pushes east of the area. Additional rounds of
rain will again pose a flooding threat. Surface high pressure will
bring another brief period of dry weather Saturday night into Sunday
before a mid-level trough with a closed low in the base tracks
across the area Sunday night into Monday which will bring yet
another round of storms to the area. Given the closed low nature of
this system it may be slow moving which may provide a prolonged
period of rainfall.

&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 547 AM CDT Tue Apr 30 2024

VFR conditions are expected through most, possibly the entire,
forecast period. The one period in question is this evening when
scattered storms may affect the terminals. Timing continues to
look like between 00Z and 04Z. Coverage continues to look
scattered in nature so have maintained the VCTS coverage. Winds
will be from the south through the day with gusts to near 30
kts. Winds become variable behind the line of storms but should
trend to a more northerly direction.

&&

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

&&

$$

DISCUSSION...73
AVIATION...CDB