976
FXUS63 KSGF 302025
AFDSGF

Area Forecast Discussion
National Weather Service Springfield MO
325 PM CDT Thu May 30 2024

.KEY MESSAGES...

- Scattered showers and a few thunderstorms tonight, mainly west
  of Highway 65. The main hazard potential will be locally
  heavy rainfall and Slight Risk (2 out of 4) of flash flooding,
  especially along and west of the I-49 corridor.

- Much better chance for widespread rain (70-90%) arrives Friday
  into Friday night. There is a Slight Risk (2 out of 4) of
  flash flooding with localized rainfall amounts of 3-5".

- Warm and muggy summer-like pattern Sunday into midweek with
  daily chances (30-60%) for showers and thunderstorms.

&&

.SHORT TERM /THROUGH FRIDAY NIGHT/...
Issued at 305 PM CDT Thu May 30 2024

Synoptic Scale Pattern and Current Conditions:

A rather complex upper-level pattern is in place across the
CONUS. Upper-level troughs are in place across the northern
Rockies and the northeastern U.S. with an amplified ridge
present from the Great Lakes into the central Canadian
provinces.

Multiple mesoscale convective vortices (MCVs) are evident on
both satellite and radar imagery. One MCV is located north of
Salina, KS. A second MCV (and an associated MCS) is located just
southeast of Wichita. A third MCV is located in the Oklahoma
City metro. Additional convection is located east of this MCV
from Stillwater, OK into northeastern Texas. These MCVs will
have implications on sensible weather across the Missouri Ozarks
and southeast Kansas over the next 36 hours.

Late this Afternoon and Tonight:

The MCS across southeastern Kansas has recently shown warming
cloud tops and reduced bowing tendencies. Both wind fields and
the presence of a NW to SE oriented instability gradient would
suggest that any remaining stronger convection within this
particular MCS should begin to dive more to the east-southeast
over the next few hours. However, MLCAPE values of 800-1200 J/kg
and little in the way of capping will promote some convective
activity making it into areas along and west of the I-49
corridor late this afternoon and early this evening.

The limited amounts of instability should preclude severe
storms- however, brief gusty winds and perhaps some small hail
can be expected with a few storms. Brief, heavy rainfall can
also be expected as a more moisture rich environment (PWATs
approaching 1.50") begins to work into the area. CAMs suggest
that rainfall rates of 1-2" per hour may be realized with some
of these storms. Outside of bow echoes, mean storm motions with
cellular activity will be rather slow. Thus, there is a limited
(2 of 4) threat for localized flash flooding starting this
evening along and west of the I-49 corridor.

Later tonight, the potential for showers and a few thunderstorms
will continue especially west of U.S. 65 as those MCVs slowly
propagate east towards the KS/MO border. The rainfall may be
somewhat spotty, as it will likely be tied to mesoscale areas
of increased lift (enhanced by a low-level jet) on the eastern
flank of the MCVs. Again, the potential for locally heavy
rainfall will continue. This will include a risk for localized
flash flooding.

Friday and Friday Night:

Upper-level short wave energy will traverse in an eastward
fashion across the Dakotas into the Great Lakes. Those MCVs will
continue to drift eastward across the Missouri Ozarks. While
models can tend to struggle with the track of these features,
there is reasonably good consensus that coverage of showers and
a few thunderstorms will increase throughout Friday morning
across western Missouri and shift east into the eastern Ozarks
during the afternoon. Activity should then slowly diminish from
west to east Friday night, however the eventual track and timing
of leftover MCVs will ultimately determine when better chances
for precipitation will begin to dwindle.

The threat for severe storms will continue to be almost nil
given a lack of instability and poor deep layer shear. However,
the threat for heavy rainfall and localized flash flooding will
continue. HREF interquartile data suggests PWATs will rise into
the 1.40-1.70" range throughout the day. Weak flow in the
atmosphere will continue to support relatively slow storm
motions. WPC has maintained a 2 out of 4 threat for excessive
rainfall for much of the Missouri Ozarks and southeast Kansas
for Friday and Friday night.

Rainfall amounts at a given location are really hard to pin down
given that mesoscale influences will be dominant. The HREF
local probability-match mean (LPMM) valid through 7 AM Saturday
paints multiple bullseyes of 2-3" rainfall amounts across the
Missouri Ozarks and southeast Kansas. In contrast, there are
also locations where the LPMM suggests that less than 0.10" of
QPF.

It should be noted that the HREF maximum QPF product suggests
very localized amounts up to five inches. This again supports
the concerns for localized flash flooding.

Temperatures on Friday will be held down due to the expected
rain and cloud cover. Some areas may not even make it out of
the lower 70s.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
Issued at 305 PM CDT Thu May 30 2024

Saturday and Saturday Night:

Most model guidance suggests that the MCV may eventually
conglomerate into a broader short wave trough and shift east
of the area. This would result in weak mid- and upper-level
height rises. While we may still see some leftover showers and
thunderstorms in the morning, primarily across the eastern
Ozarks, most areas should be dry.

Sunday and Monday:

Ensembles suggest that the upper-level flow will be fairly flat
sans weak embedded short wave troughs. The timing and placement
of such features is quite variable upon member inspection.
There appear to be two potential scenarios for possible
convection. One would be afternoon pop-up storms as the
environment becomes uncapped. Another potential scenario would
be an MCS or two rolling in off the Plains. We have kept PoPs
in the 40-60% range for much of the period with the highest PoPs
on Monday.

Temperatures will be seasonably warm with the NBM showing good
clustering around highs in the lower 80s. It will be rather
muggy as dew points creep back up towards 70 degrees.

Tuesday into Wednesday:

Ensemble cluster scenarios indicate a stronger short wave trough
progressing through the central U.S. This includes a cold
front sweeping through the region sometime in the later Tuesday
to early Wednesday time frame. This setup would favor another
potential round of thunderstorms. CIPS and CSU machine learning
products do indicate at least some limited severe thunderstorm
potential with this setup.

Thursday:

Most ensemble scenarios indicate the front should be far enough
east for a return to dry weather. We should see a slight cool
down and a drier air mass behind the departing front with
temperatures fairly close to normal.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1214 PM CDT Thu May 30 2024

Multiple upper level disturbances will bring lowering ceilings
and increasing rain potential from this evening into Friday.
Rain chances and increasing MVFR potential will start at Joplin
around 00Z as showers and a few thunderstorms push out of
eastern Kansas.

More in the way of widespread rainfall will then shift from west
to east across southern Missouri from late tonight into Friday
morning. Widespread MVFR ceilings will transition to IFR
throughout the morning. Pockets of heavier rainfall will also
result in MVFR and brief IFR visibilities. A few thunderstorms
are also expected Friday morning in the vicinity of Joplin.

Surface winds throughout the TAF period will generally remain
out of the southeast at 6-12 knots. There will be gusts around
20 knots until sunset at Joplin and Springfield.

&&

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

&&

$$

SHORT TERM...Schaumann
LONG TERM...Schaumann
AVIATION...Schaumann