413
FXUS63 KEAX 090818
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
318 AM CDT Sun Jun 9 2024

.KEY MESSAGES...

- A complex of showers and thunderstorms moves through the area
  overnight. Much of the activity will remain south of
  Interstate 70. Primary threats are for heavy rainfall leading
  to potential flash flooding. Isolated strong to severe storms
  with damaging winds and hail cannot be ruled out in the short
  term.

- Cooler conditions expected Sunday with a drier pattern
  anticipated through the first half of the work week.

&&

.DISCUSSION...
Issued at 318 AM CDT Sun Jun 9 2024

Thunderstorms developing along a CAPE boundary draped across
southwest MO. The low level jet looks like it has not migrated
as far north as initially anticipated which has resulted in
the line of storms developing a little further south. The good
news about this is that this area did not receive as much rain
from the showers and thunderstorms that moved over the area
Friday into Saturday. However, RFC flash flood guidance still
resides around 1.5 to 2 inches per hour and 2 to 3 inches per 3
hours. With PWAT values ranging from 1.5 to over 2 inches, those
rain rates are plausible as storms are expected to be highly
efficient rain producers. With storm motions being from west to
east parallel to the orientation of the front, this sets up a
situation where storms will train over areas for several hours.
A Flash Flood Warning has already been issued for Linn County KS
as a radar estimated 2-4 inches of rain has fallen resulting in
exceedance of the earlier mentioned flash flood guidance.

Over the course of the night, more stratiform precipitation is
expected to move in from the west. The CAPE gradient which the
thunderstorms current reside, sags southward. More robust
convection across central KS is expected to follow this gradient
and likely pass south of the area. A few strong storms may clip
the souther portions of the coverage area bringing brief
moments of torrential rainfall. As the MCV tightens up,
stratiform precipitation is expected to expand northward
potentially enveloping the KC metro and some areas north of
I-70. Rain rates with this broad precipitation are expected to
be less; however, an isolated patch of heavy rainfall cannot be
ruled out. While flooding concerns are relatively decreased
compared to 24 hours ago, the potential for pooling and ponding
in urban areas remains. Please exercise caution if traveling as
flooded roads may be difficult to see at night. This system is
expected to move out the area during the post sunrise hours with
some lingering showers possible through mid morning.

Northwest flow and midlevel high pressure then start dominating the
forecast regime. This results in cooler and drier conditions.
Saturday brought a little taste of summer with dew points around 70
degrees. Fortunately, Sunday looks to be more pleasant with dew
point sinking back into the mid to upper 50s. Highs range in the
upper 70s to low 80s. The upper level pattern continues this
northwesterly pattern for the early part of the week. Interestingly,
part of the reason in the pattern stagnation is due to a cutoff low
pressure that stalls off the southern CA coast. This shifts westerly
flow across the northern Rockies which is then turned toward the
southeast due to a stout low across the NE CONUS. Model guidance has
been hinting at a small embedded shortwave creating a leeward
cyclone Tuesday; however, there remains much uncertainty on the
track and intensity of this cyclone. At the moment, it is looking
like the system and associated rainfall will miss the area.

The cut off low looks to reintegrate into the overall upper level
pattern toward the end of the week setting up for a return of
showers and thunderstorms for the upcoming weekend. Reopened
southerly flow to the Gulf increases plausibility for strong
thunderstorm, but it is too far out to speculate at this time.
Extended guidance is pointing toward a pattern shift as the
summer solstice approaches. Namely, an expansive high pressure
building across the central and southern CONUS resulting in
hotter and drier conditions. However, models have not given up
on embedded shortwaves and leeward cyclones bringing further
rainfall chances; keeping the dog days of summer at bay for the
time being.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1217 AM CDT Sun Jun 9 2024

VFR conditions prevail through most of the period. Rain showers are
anticipated within the first few hours of the TAF period, with model
guidance keeping the most intense rain south of the sites. Ceilings
associated with rain showers do have the potential to briefly lower
to MVFR thresholds, but uncertainty remains with this possibility.
Skies are expected to clear starting around 15Z Sunday morning.
Clearing is expected to start earlier for STJ. Winds will be out of
the northeast around 5-10 knots, becoming slightly more
northeasterly as the TAF period progresses.

&&

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

&&

$$

DISCUSSION...Pesel
AVIATION...Hayes