775
FXUS63 KEAX 090800
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
300 AM CDT Tue Jul 9 2024

.KEY MESSAGES...

- The remnants of Beryl will bring rain and isolated
  thunderstorms in far southern and eastern portions of the
  forecast area today. Excessive rainfall should remain south
  and east of the region.

- Isolated to scattered thunderstorms are expected to develop
  Wednesday afternoon, primarily in areas east of I-29 and north
  of I-70. An isolated strong to severe storm cannot be ruled
  out.

- Increasingly hot and humid conditions are expected to build
  into the region late this week through early next week. Daily
  maximum heat indices exceeding 100 degrees are quite likely
  (>80 percent chance) by Sunday.

&&

.DISCUSSION...
Issued at 224 AM CDT Tue Jul 9 2024

The remnants of Beryl are swiftly progressing northeastward in
western Arkansas early this morning, with a shield of rain and
embedded thunderstorms northeastward through southern and
eastern Missouri and southern Illinois. This general motion will
continue today, keeping the low`s track well to our southeast.
However, the northwest periphery of the precipitation shield
will glance our far southern and eastern zones today,
particularly after daybreak as the convection diurnally expands
surrounding the core of the system. The highest chances of
precipitation remain south and east of a Pleasanton, KS, to
Kirksville, MO, line, with areas to the north and west most
likely to receive little or nothing. Meanwhile, areas close to
the southern/eastern CWA borders may reach (in an areal-average
sense) up to a quarter or half inch. The cutoff in the
precipitation is expected to be sharp, so there remains quite a
bit of uncertainty with the QPF. A subtle shift southeastward
in the track may result in little or nothing for our entire CWA.

There are a couple of interesting scenarios to watch today.
Convection-allowing models (CAMs) have been suggesting the
development of convection on the northwestern edge of the
precipitation this morning (perhaps as a result of
convectively-induced boundaries translating northward), similar
to the region in which convection developed last evening. Given
the thermodynamic environment, any such convection would
produce efficiently high precipitation rates. Given the locally
heavy rainfall in portions of Bates, Cass, Johnson, and Henry
counties last evening (and portions of Cooper, Saline, and
Pettis counties the previous night), this will need to be
monitored closely should these storms develop.

A second scenario has been hinted at in a minority of CAMs this
afternoon. As the precipitation shield moves east of the region
during the afternoon, sufficient diabatic heating west of the
cloud/precipitation shield may result in isolated to widely
scattered storms, primarily in far east-central Kansas and
west-central Missouri. This is a low-probability scenario, given
its low frequency of occurrence in the CAMs and any such
development within a region of general large-scale descent.
Nevertheless, it is not out of the question to see a storm or
two during peak heating this afternoon west/northwest of the
departing system.

Temperatures should remain mild today, with considerable cloud
cover in most of the area. Highs may remain in the 70s near our
south/east CWA border, and in the 80s elsewhere. The region will
be dry tonight, with lows in the 60s.

A potent shortwave trough will dig southward from the Upper
Midwest tomorrow, approaching the Corn Belt during the
afternoon, as it acts to kick Beryl rapidly northeastward. Cool
temperatures aloft atop a diurnally destabilizing and well-mixed
boundary layer will set up an environment favorable for
scattered convection by afternoon. Ensemble probabilities of
precipitation have increased 10 to 20 percent from yesterday
during the afternoon and early evening. CAMs are hinting at this
potential as well, especially in north-central/northeast
Missouri. Model soundings are supportive of pulse-type
convection with SBCAPEs of 1000-2000 J/kg and deep-layer shear
generally less than 30 kt, with fairly weak flow in most of the
troposphere. However, the cool temperatures aloft and the
inverted-v profiles in the low levels suggest at least some
potential for hail and strong wind gusts with the most vigorous
convective cores. Cannot completely rule out a briefly severe
storm or two during the afternoon and early evening. Convection
should wane quickly after sunset. This potential may exist again
on Thursday in far northeast portions of the CWA, but the better
potential is to our east, given the progression of the shortwave
trough in that direction.

Meanwhile, the scorching ridge in the western U.S. will build
eastward into the central U.S. upstream of Beryl`s remnants.
This will result in increasing heat/humidity late in the week
through the weekend, with mostly dry conditions. Ensemble
probabilities of temperatures exceeding 95 degrees by Sunday are
well above 50 percent for the western half of the area, with
Monday being even hotter. Heat indices well above 100 degrees
are likely (>80 percent chance) Sunday and Monday, with heat
headlines during this period probably necessary should forecast
trends continue.

&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1248 AM CDT Tue Jul 9 2024

The remnants of Beryl continue to make their approach to the
central U.S. early this morning, but precipitation is still
expected to stay safely southeast of the terminals today. Even
ceilings will remain VFR, with sky cover expected to diminish
late today and tonight. Light and variable winds early this
morning will become predominantly northerly after 12z, remaining
generally under 10 kt.

&&

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

&&

$$

DISCUSSION...CMS
AVIATION...CMS