582
FXUS63 KEAX 191121
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
621 AM CDT Sat Apr 19 2025

.KEY MESSAGES...

* Cooler conditions expected today with light rain expanding from
  the south this afternoon into tonight.

* Area of low pressure will move through the central US on
  Sunday bringing heavy rain and the potential for severe
  weather. These threats will largely be concentrated during the
  daylight hours on Sunday. Flood watch remains in effect for
  central Missouri through Sunday.

* Additional chances of thunderstorms are possible late on
  Tuesday into late week.

&&

.DISCUSSION...
Issued at 346 AM CDT Sat Apr 19 2025

Isentropic lift on the 305K surface is expected to decrease towards
12Z as surface ridge across the Northern Plains increases the
influence across the immediate region leading to drier conditions
through the better part of the day today; however, as low pressure
develops in west Texas and lifts northeast into central TX the
stationary boundary along the I-44 corridor is expected to lift back
north as a warm front bringing light rain with it.  Light rain will
expand from south to north this afternoon into tonight leading to
warmer temperatures in the drier conditions across northern Missouri
than areas farther south. Low level jet extending from the gulf
northward into the plains will usher unseasonably moist air into the
region with precipitable water values of 1.25 -1.50", close to daily
max values for this time of year.

As the low pressure system builds north, lift will increase
especially through the morning hours on Sunday. Isentropic lift is
strongest across eastern Kansas through the morning hours
potentially leading to a brief break farther east allowing the
atmosphere to destabilize.  Strongly sheared environment, 0-6 km
Bulk shear > 60 knots) along with little capping inversion will
readily allow any instability to increase intensity of any
thunderstorms that develop. Models hint that atmosphere may develop
as much as 1000 J/kg of surface based CAPE immediately ahead of
trough moving through the region on Sunday afternoon.  Several
models suggest linear convective mode quickly developing along the
trough axis.  With coordination with SPC, have expanded the
enhanced severe weather threat for Sunday to include locations
within the warm sector, which looks to be roughly south of the
highway 36 corridor.

Severe threat looks to decrease across the region fairly quickly
Sunday evening as trough axis shifts east of the area and low
pressure lifts northeast into Iowa.

High pressure briefly builds into the region on Monday leading to
drier conditions, but area of low pressure develops over the
Northern Plains on Tuesday. Steep mid level lapse rates ahead of the
front lead to 1000-1500 J/kg of CAPE that may result in the
potential for late day storms as trailing cold front attempts to
work south. Front is expected to stall across the region, as a
series of short waves track across the region in zonal flow leading
to additional chances of rain late week.

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 616 AM CDT Sat Apr 19 2025

Light rain across the region is expected to remain focused
closer to the I-44 corridor today with northeast winds
prevailing, but towards 00Z rain and lower ceilings will build
north across the region through the overnight. Ceilings are
expected to fall into the MVFR range overnight, and towards IFR
Sunday morning after 12Z.

&&

.HYDROLOGY...
Issued at 346 AM CDT Sat Apr 19 2025

Periods of showers and thunderstorms through Sunday are
expected to lead to two to three plus inches of rainfall mainly
south of I-70, with the heaviest rainfall near or just north of
I-44. This rainfall could lead to rises along area streams and
rivers, especially the Blackwater and Lamine Rivers as well as
Big Creek in the vicinity of Blairstown. Ensemble guidance
indicates at least some potential for minor flooding on the
Petite Saline, the Marais Des Cygnes (at La Cygne), and Moniteau
Creek at Fayette. Considerable uncertainty remains with
rainfall totals, with a sharp drop-off in accumulations on the
north side of the precipitation shield anticipated. As a result,
the flood watch remains unchanged at this time.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...Flood Watch through Sunday evening for MOZ045-046-053-054.
KS...Flood Watch through Sunday evening for KSZ060.

&&

$$

DISCUSSION...BT
AVIATION...BT
HYDROLOGY...CMS/BT