128
FXUS63 KEAX 042311
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
611 PM CDT Sat May 4 2024

.KEY MESSAGES...

- Line of strong to severe thunderstorms expected late Monday
  evening through the overnight. Damaging wind, hail, and a few
  tornadoes cannot be ruled out.

- Heavy and persistent rainfall with thunderstorms Monday night
  may result in increased flooding and flash flooding
  potential.

- Active weather pattern continues Tuesday through the end of
  next week.

&&

.DISCUSSION...
Issued at 206 PM CDT Sat May 4 2024

Mid-level short wave trough continues to lift east-northeast from
Nebraska into Iowa this afternoon, with surface ridging building
into eastern Kansas into Missouri, post surface frontal passage. 18Z
analysis reveals the surface front has reached the Ozark Plateau.
Behind the front, northwest winds remain breezy, with stratus spread
across most of the region. Dry conditions are expected for the
remainder of the day, with highs in the mid-60s for most, reaching
the mid-70s for those with abundant sunshine this afternoon.

Sunday, a deepening western trough will emerge into the Inter-
Mountain West through the morning. What little brief mid-level
ridging we had will be interrupted by an H500 short wave tracking off
the Southern Plains into the Ozarks through midday. Guidance has
maintained rather consistent solutions, lifting the short wave along
the Boston Mountains and onto the Ozark Plateau through the day.
This should keep the bulk of precipitation/storm chances well to the
south of our region, but will keep slight to chance PoPs in place
along the Truman to Lake of the Ozarks region to account for the
track of this system. No severe weather is expected this far north
given lack of appreciable instability and shear.

Monday, conditions look ripe for severe convection across the
Central Plains. The western trough mentioned above will pivot and
take on a strong negative tilt as it enters the western High Plains
through Monday morning. With unobstructed return flow from the gulf,
a moisture rich boundary layer, and steepening mid-level lapse
rates, a ribbon of robust instability will develop from south
central Nebraska, south, through Kansas. MLCAPE values will push
1500 to 3500 J/Kg). Increasingly favorable wind profiles will result
in 40 to 55 kts of 0-6km bulk shear. Initial convection will more
than likely be single cell, supercellular in nature, and given the
thermodynamic profiles at play, they will be capable of large
damaging hail, upwards of baseball size, perhaps larger. The tornado
risk will increase through the afternoon as 0-1km helicity increases
across southeast Nebraska and south-southwest across eastern Kansas.
0-1 km helicity values approach 200 m^2/S^2. As storms move across
eastern Kansas through the early evening, the expectation is for
them to grow upscale into a more linear mode. This is what the focus
will be on for our region. Mid-range solutions suggest the line of
storms arriving into far eastern Kansas and western Missouri between
8 and 10 PM CDT. Damaging winds will be primary concern with the
surge of the line east through the late evening period. The risk of
embedded QLCS spin-ups or maintained embedded supercellular
structures early will exist given 0-3km shear in excess of 300
m^2/s^2 and 2000 J/Kg MLCAPE. It will be a bumpy Monday night as
storms roll through.

Tuesday, storms will be lingering to the east, across central into
eastern Missouri through the early morning. This activity may
maintain a severe wind threat through the early morning. Generally
the forecast for the remainder of the day is rather tricky given the
broad H500 trough that will stretch from the west coast to the Great
Lakes. Subtle short wave impulses riding the broader flow may result
in continued chances for showers and storms. As the larger, parent
trough, evolves east, an embedded short wave will emerge off the
northern Plains and bring another chance for thunderstorms to the
region Wednesday afternoon and evening. Overall, the pattern remains
unsettled through the end of next week.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 611 PM CDT Sat May 4 2024

Expect to see improvement in MVFR ceilings fairly
quickly this evening with VFR expected around
01z. Otherwise light northerly winds through the
night gradually turn more easterly tomorrow. Think
any rain chances should stay mostly south of the
TAF sites.

&&

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

&&

$$

DISCUSSION...Kurtz
AVIATION...HB