921
FXUS63 KEAX 040908
AFDEAX

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

.KEY MESSAGES...

- Scattered showers and thunderstorms will move through the
  area this morning. A few strong storms may be possible.

- Widespread showers and thunderstorms are likely Monday night
  into early Tuesday morning. Large hail, damaging wind gusts, a
  few tornadoes, and locally heavy rain will all be possible.

- The active weather pattern continues into Tuesday and
  Wednesday, with strong to severe storms possible.

&&

.DISCUSSION...
Issued at 246 AM CDT Sat May 4 2024

A line of thunderstorms is ongoing from southwestern Iowa,
through extreme NW Missouri, and into eastern Kansas as a
shortwave trough and associated cold front are working their way
from the Central Plains into the Midwest. As of 3 am, the most
robust storms are located just east northeast of Manhattan KS
(reports of dime sized hail and wind gusts up to 45 mph) with
these moving to the northeast. SPC mesoanalysis shows a corridor
of 250 to 500 J/kg of surface based CAPE over far eastern KS
into far western/NW MO, with up to 1000 J/kg of most unstable
CAPE. Up to 35 knots of 0 to 6 km wind shear is in place over NE
KS and NW MO, with weaker shear elsewhere. This suggests that
the most likely location for any stronger storms would be across
NE KS and NW MO. Total rainfall amounts should range from 0.5"
to 0.75" in this area. Storms should weaken east they continue
eastward later this morning, and convection allowing models keep
the KC metro mostly dry this morning. New development of
showers and storms is possible ahead of the cold front this
afternoon from Kirksville southward toward Columbia, with these
exiting the county warning area by late afternoon. Cloud cover
will likely linger into the mid to late afternoon hours, with
winds turning northwesterly and eventually northerly behind the
cold front. The timing of the front will create a relatively
large temperature gradient for high temperatures today, with
highs only forecast to reach the lower 60s over NW Missouri but
highs as warm as the mid to even upper 70s toward mid Missouri
where the front will likely not arrive until mid afternoon.

By tomorrow afternoon, a 548 dam closed low at 500 mb moves into the
Grand Basin region of Nevada and Utah, with associated troughing
moving into the Desert Southwest. Meanwhile, a more subtle shortwave
trough develops over the ArkLaTex region and sends the stalled
cold front over the Arkansas Ozarks northward. This could
generate some showers and thunderstorms on Sunday afternoon,
especially for areas south of Interstate 70, although the
better chances should stay south of our region toward the
Interstate 44 corridor.

As we head into Monday, a potent mid/upper trough comes across
the Southern Rockies, undergoing lee cyclogenesis and
progressively becoming more negatively tilted as it ejects
across the Central and Northern Plains. Models have come into
better agreement, suggesting a deep surface low developing over
the Northern High Plains, with a warm front extending east/west
over NE/IA and a dryline extending southward through west-
central KS and Oklahoma by Monday afternoon. With good moisture
return, moderate to high instability, and excellent deep layer
shear thanks to a 50 to 70 knot mid level jet, supercells with
highly impactful severe weather of all types appears likely
Monday afternoon and evening across portions of southern
NE/central KS/central OK. It seems likely that these storms will
grow upscale into a severe squall line/MCS as they progress
eastward toward our region on Monday evening. Prime time for our
region appears to be late evening into the overnight/early
morning hours of Tuesday. If any storms do manage to develop out
ahead of the expected squall line, all severe hazards would be
very much in play. However, if it is a squall line, damaging
wind gusts and potentially some embedded QLCS mesovortex
tornadoes would likely be the main concern. Additionally,
widespread moderate rain is likely, with rainfall totals on the
order of around 1 inch with locally higher amounts possible,
potentially yielding more flash flooding and river flooding.

The active pattern continues on Tuesday and Wednesday as the
closed mid level low is progged to remain over the Northern
Plains with southwesterly flow aloft over our region. With
moderate instability and strong deep layer wind shear hanging
around Tuesday and Wednesday afternoon/evening, strong to
severe thunderstorms will remain possible. As such, SPC has
highlighted portions of our county warning area within a 15%
risk for severe storms for both Tuesday and Wednesday.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 1209 AM CDT Sat May 4 2024

Currently VFR with around 10 knot winds out of the southeast at
all terminals. A broken line of showers and thunderstorms will
approach the terminals by around 10 to 11z this morning, with
these exiting by around 14z. A few isolated showers may linger
through late morning. MVFR CIGs arrive with the showers, with
these continuing through around 22z this afternoon, after which
VFR CIGs should return. Winds shift to northwesterly and
eventually northerly behind a cold front this morning.

&&

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

&&

$$

DISCUSSION...BMW
AVIATION...BMW