869
FXUS63 KSGF 180524
AFDSGF

Area Forecast Discussion
National Weather Service Springfield MO
1224 AM CDT Tue Aug 18 2026

.KEY MESSAGES...

- Heat ramps back up on Tuesday and through the end of the week,
  with a Heat Advisory in effect on Tuesday from 1 PM to 8 PM.

- Marginal (Level 1 of 5) to Slight (Level 2 of 5) Risk of
  severe storms very late Tuesday night into Wednesday morning
  as a storm complex moves through central Missouri, with
  damaging winds being the primary severe hazard.

- Marginal (Level 1 of 5) to Slight (Level 2 of 5) Risk of
  severe storms again Wednesday evening as another storm
  complex develops across southern Missouri. Damaging winds are
  the primary severe hazard, though hail and tornadoes could be
  possible if the ingredients align properly.

- Excessive rainfall leading to flooding will be possible with
  any/all storms between Tuesday night and Thursday morning.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 140 PM CDT Mon Aug 17 2026

Current Conditions & Synoptic Overview:

High pressure is building across the region in the wake of a
cold front that moved through the area last night. The region is
in northwest flow in the mid-levels as the persistent ridge of
the last week has been broken down, though ridging is re-
developing across portions of the Intermountain West.

Today/Tonight:

High clouds are across the area this afternoon as a result of
storms to our south in Arkansas along the cold front. This,
paired with the NW flow aloft, is helping to keep temperatures
much cooler this afternoon, with temperatures early this
afternoon only in the mid-80s. As afternoon mixing increases,
winds could intermittently gust up to 20 mph this afternoon, but
would decrease after sunset. Dew points in the mid-60s this
afternoon will help it feel less muggy today than the last
several days. Skies should clear overnight, and lows in the 60s
may result in some patchy fog in the eastern portions of our
forecast area.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Issued at 400 PM CDT Mon Aug 17 2026

Heat:

A plume of southwesterly winds push back across the Central
Plains towards our area ahead of lee cyclogenesis in western
Kansas on Tuesday, bringing back warm air to the region. A warm
front should start pushing into our area from the southwest by
Tuesday afternoon, increasing our temperatures back into the 90s
areawide. Far western and southern portions of our area will
likely breach 100 degrees, bringing heat indices back into the
105-110 degree range for Tuesday. For that reason, our Kansas
counties and the far western tier of our Missouri counties as
well as some of our Missouri counties along the Arkansas border
have been added to a new Heat Advisory from 1 PM to 8 PM on
Tuesday. Depending on the speed and timing of the warm front, it
is possible an eastward expansion of the Advisory may be needed
in subsequent forecast packages.

The presence of convection during the day on Wednesday will have
implications on temperatures (and thus heat indices) and whether
or not areas reach Heat Advisory criteria again on Wednesday. It
is likely to be a similar area to Tuesday where heat indices
may meet or exceed 105 degrees on Wednesday, especially if
convection remains confined to areas east of Interstate 49 as is
currently expected. This uncertainty prevented Heat Advisory
issuance for Wednesday at this point, though it may or may not
need to be added in coming days. Additional heat concerns
continue through the week, with the four days of 100+ heat
indices criteria potentially being met in the western and
southern portions of our area, leading to the potential for
additional Heat Advisory issuance through at least Friday.
However, Tuesday and Wednesday`s convection will have
implications on the pattern for the rest of the week, so that
will be something to watch closely if in heat-sensitive
industries or outdoors this week.


Severe Weather Risk Tuesday Night/Wednesday Morning:

Very late Tuesday night into early Wednesday morning, an MCS is
progged to develop along the nose of the nocturnal LLJ as a
shortwave moves across northern Missouri. The lee cyclogenesis
in Kansas will also help to sustain isentropic ascent during
the overnight hours, though the primary question regarding this
overnight MCS remains what the forcing mechanism will be that
initiates the complex that moves into our area. Another storm
complex further north into Nebraska may influence how conditions
evolve throughout the day, though it does appear likely that
this northern MCS will send an outflow boundary surging south
into central Missouri that will be the likely initiation
mechanism for storms in our area. Storms appear to initiate
north and west of our area in Kansas before moving into western
Missouri, with most CAMs that initiate this activity indicating
that storms organize into clusters by the time they reach our
area.

With the boost in the LLJ to 30-40 kts overnight, 0-3km bulk
shear values increase to 50-60kts by 12Z Wednesday, which would
support strong cold pool development and damaging wind gusts
with this cluster of storms. Hodographs are sufficiently curved
that there may be a conditional threat for QLCS tornado
development as well, especially as storms progress south and
east and approach the warm front spread across the area. Best
severe chances remain along and northwest of the greater Lake of
the Ozarks/Truman Lake corridor, which is within the Slight
Risk (Level 2 of 5) area from SPC.


Severe Weather Risk Wednesday:

Scattered showers and storms may continue on and off during the
day on Wednesday after the progression of the late Tuesday night
system, but the 12Z model suite is increasingly pointing
towards another area of severe weather potential on Wednesday
evening/night across portions of southern Missouri into
northern Arkansas as the shortwave aloft progresses from Kansas
into Missouri. Southern portions of the state have the best
instability available (1000-2000 J/kg MUCAPE) as the nocturnal
LLJ ramps back up. An MCS appears to be the most likely cause of
severe weather, with the primary threat being damaging winds
during the evening/overnight hours as storms become more
organized. However, storms may initially form as supercells or
supercell-like clusters in southwest Missouri, with straight
hodographs during the afternoon to early evening hours
suggesting initial storms may be prone to splitting. As such,
cannot fully rule out hail with strongest afternoon storms.
30-40kts of 0-3km shear could again support mesovortices
embedded within the larger storm clusters, especially once the
LLJ begins increasing low-level hodograph curvature. As the
nocturnal LLJ ramps up, storms should become more organized into
a bowing segment(s) as cold pools organize along the LLJ and
shear strengthens, where the damaging wind threat is most likely
to materialize.

While there is still a fair amount of uncertainty regarding the
placement and overlap of key mesoscale features in the wake of
the overnight convection, model consensus agrees that there is a
sufficient risk for severe weather on Wednesday. As such,
collaboration with SPC has resulted in bumping southern
portions of the area up from a general thunderstorm risk to a
Slight (Level 2 of 5) Risk with much of the other part of our
area within a Marginal (Level 1 of 5) Risk for severe weather on
Wednesday into Wednesday night.


Hydrology/Excessive Rainfall Concerns:

PWATs increase Tuesday to between 1.75-2", with a plume of
2-2.3" PW values advected south with the late Tuesday
night/early Wednesday morning MCS/round of rainfall. Numerous
CAMs indicate the potential for heavy rainfall with the
convective systems (and individual storms) that occur between
Tuesday night and Thursday morning, with 6 hour LPMMs of 2-3"
for a given round of rainfall, which could trigger rate-driven
flash flooding concerns in areas that see the strongest rainfall
rates. Corfidi vectors and mean wind vectors are aligned with
the theta-e gradient, which would suggest training is possible with
both rounds of storms, which would also increase the threat of
localized heavy rainfall and flash flooding potential.

&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1220 AM CDT Tue Aug 18 2026

VFR conditions will prevail through the entirety of the TAF
period. Surface winds will become southerly by late morning,
generally remaining below 10kts.


&&

.SGF WATCHES/WARNINGS/ADVISORIES...
KS...Heat Advisory from 1 PM this afternoon to 8 PM CDT this
     evening for KSZ073-097-101.
MO...Heat Advisory from 1 PM this afternoon to 8 PM CDT this
     evening for MOZ066-077-088-093-101>104.

&&

$$

SHORT TERM...Camden
LONG TERM...Camden
AVIATION...Melto