386
FXUS63 KEAX 201728
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1228 PM CDT Sun Apr 20 2025

.KEY MESSAGES...

* Rounds of showers and thunderstorms are expected across the
  region today. Expanded flood watch across central Missouri
  today.

* Severe weather threat possible this afternoon. Mainly from
  areas along and southeast a line from Butler, Carrollton,
  Macon to Kirksville. Main threat is damaging wind, large hail,
  and also isolated tornado threat mainly from Linn County KS
  to Howard County MO.

* Drier conditions develop on Monday into Tuesday before more
  unsettled pattern redevelops late week.

&&

.DISCUSSION...
Issued at 355 AM CDT Sun Apr 20 2025

Increasing isentropic lift leading to rain building from south to
north across the area this morning as strong area of low pressure
lifts from northern Texas toward the central US. Diffuse warm front
as of 08Z across northern Arkansas is expected to lift northward
this morning approaching the southern CWA border towards 15Z.
Increasing near surface moisture in the vicinity of the front could
lead to weak elevated instability (100-300 J/kg of elevated CAPE)
resulting in a renewed threat for showers and thunderstorms late
this morning. As low pressure pinwheels to the north, warm sector of
the low is expected to build into central Missouri with 60+ F degree
dewpoints south of the front. This will be the area to watch through
the afternoon hours to see whether a gap in the precipitation can
develop allowing instability to build in the atmosphere increasing
the severe weather threat. Strong speed and directional shear
leading to 50-60 knots of 0-6 km bulk shear. Model soundings suggest
a fairly shallow cap in place, so it may be difficult to build
substantial instability (500-1000 J/kg of CAPE), making the severe
threat conditional. If instability can develop, all severe weather
modes are possible as storms develop ahead of cold front moving east
through the afternoon hours.  CAMs have suggest storms may try to
organize into a linear mode along this feature, with the potential
for isolated to scattered clusters ahead of the line. 0-1 km SRH
along this feature could vary from 150-250 m2/s2, suggesting
organized rotation with ample instability.

CAMs (especially the HRRR) have also trended wetter along and east
of a line from Clinton to Kirksville. Have expanded the flood watch
through 00Z this evening to include a larger portion of central
Missouri east of the KC metro.

Precipitation is expected to come to an end across the region this
evening leading to drier conditions on Monday as strong low lifts
into the western Great Lakes region; however, a second but much
weaker low is expected to develop across the Northern Plains as an
open wave trough moves across the Dakotas. This feature looks to
remain largely to the north, but phased short waves farther south
move east in zonal flow potentially generating thunderstorms across
Kansas building east into the region Tuesday night/Wednesday
morning.

Additional storm chances are possible late week, but have not spent
much time on the extended with active weather in the short term.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1220 PM CDT Sun Apr 20 2025

MVFR and IFR ceilings expected through the afternoon
the next round of showers and thunderstorms continues to move
northeast through central portions of the CWA. The next round of
storms after 19z will have the potential of producing strong wind
gusts, especially east and southeast of the KC metro area and TAF
sites. Further south and east from Linn County KS to Howard
County MO, there is stronger storms with potential for tornadoes
and wind. Precipitation is expected to remain into eastern MO
and IA through 00z. Skies are expected to gradually clear from
west to east late Sunday night into Monday morning, expect those
gusty winds to linger in through the night to 09-11z.


&&

.HYDROLOGY...
Issued at 403 AM CDT Sun Apr 20 2025

Excessive rainfall of 1-4+ inches with locally higher amounts
may lead to both flash flooding and river flooding today. The
greatest concern for flash flooding is through the afternoon
hours today, when 1-3+ inches are possible. The area of
greatest concern is east of a line from Clinton to Moberly.
River flooding is possible along the South Grand, Petite Saline,
Lamine, and Big Creek, as well as larger basins like the
Blackwater and the Marias Des Cygnes.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...Flood Watch until 7 PM CDT this evening for MOZ032-033-038>040-
     044>046-053-054.
KS...Flood Watch until 7 PM CDT this evening for KSZ060.

&&

$$

DISCUSSION...BT
AVIATION...WFO EAX
HYDROLOGY...CDB