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106
FXUS63 KSGF 232024
AFDSGF

Area Forecast Discussion
National Weather Service Springfield MO
324 PM CDT Sun Jun 23 2024

.KEY MESSAGES...

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- A Heat Advisory is in effect for the entire area Monday from
  noon until 8 PM. Highs will be in the middle to upper 90s with
  Heat Index values between 100 to 110.

- Daily high temperatures in the upper 80s to mid-90s through
  this week, with Heat Index values ranging in the 90s and into
  the 100s.

- Scattered thunderstorm chances Tuesday into Wednesday, with
  highest chances (40 to 70%) late Tuesday night.
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&&

.SHORT TERM /THROUGH MONDAY NIGHT/...
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Issued at 324 PM CDT Sun Jun 23 2024

Current surface observations have light and variable winds
across our CWA as a weak/diffuse cold front is progged along the
southern MO border. Despite this, temperatures are already
around 90 F, except for areas toward central MO which are near
88 F. These are still on track to hit 90 F or above this
afternoon. Modestly stronger mid- and upper-level flow
associated with this front can be seen in water vapor imagery
across central MO/KS. The weaker flow and higher geopotential
heights are located south of the cold front along the MO/AR
border where highs will be greatest (near 95 F) and Heat Indexes
approaching the 100-105 F range. With the frontal boundary still
lingering tonight, there will be a gradient in low temperatures
with lows in the mid-60s across the eastern Ozarks, and
temperatures in the mid-70s near the MO/KS/OK borders.


Heat Advisory in effect for the entire area Monday from 12-8 PM:

The upper-level high over the Four Corners region will begin to
build back into the region Monday. Moving in with it, a
synoptically-forced 850 mb ridge will translate eastward into
the ArkLaTex region. SW`ly 850 mb winds north of the ridge will
advect 23-25 C temperatures over MO. This combined with adiabatic
warming from the synoptic subsidence of the upper-level high,
and clear skies, will allow high temperatures to reach the
middle to upper 90s, even close to 100 F in some areas. For some
examples, Joplin is given a 60-80% chance of breaking the 100 F
mark, Springfield is given a 30-40% chance, and the Branson to
Ava area is given a 70-90% chance (these are also the general
chances for each location to break their record high for
Monday).

With dewpoints in the upper 60s to lower 70s, Heat Indexes will
reach the 100-110 F range. With widespread areas forecast to be
above 105 F, a Heat Advisory has been issued for Monday from
12-8 PM. Winds will pick up a bit Monday as the boundary lifts
back north as a warm front. This is reflected in Wet Bulb Globe
Temperatures in the middle to upper 80s (earlier forecasts had
them breaking 90 F which is labeled as "Extreme Risk" for
outdoor workers and athletes). While this will temper max heat
stress a bit, it is still forecast to be the hottest day of the
series, and practicing heat safety will be of the utmost
importance. This includes limiting outdoor activity, but taking
frequent cooling breaks if required to be outdoors, checking on
family members and friends, drinking plenty of water, and
avoiding leaving pets and children unattended in vehicles.

Low temperatures in the middle to upper 70s Monday night will
provide very little relief to the heat experienced during the
day Monday and going into Tuesday. Some areas may stay near 80 F
at the MO/KS border, which is only 5-8 degrees below a normal
high for around this time of year. Yikes! It goes without
saying then that some areas may break their record high minimum
temperatures Monday night.


Very slim shower and thunderstorm chances Monday afternoon:

Despite PoPs being below 10% Monday afternoon, a few HREF CAMs
are indicating the potential for a few isolated pop-up showers
and thunderstorms along the MO/AR border. Current thinking is
that CAMs are out to lunch since synoptic subsidence will be
quite strong, which would contribute to greater capping than
what`s currently modeled by CAMs (this is a known Hi-Res
bias/flaw). Nevertheless, did want to at least briefly mention
the possibility since some CAMs are displaying that scenario.
Current confidence is high that <10% PoPs will hold, though.
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&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
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Issued at 324 PM CDT Sun Jun 23 2024

Scattered thunderstorm chances Tuesday into Wednesday (40-70%):

Stronger NW`ly flow will overspread the region Wednesday. Two
shortwaves are expected to move through this pattern. A subtle
one will drop through during the day Tuesday, and a stronger
one will drop through the Great Lakes region Tuesday night into
Wednesday. The stronger wave will have a surface cold front
associated with it which will be located over north MO by
Tuesday evening. Showers and thunderstorms are expected to
develop ahead of the front and move south as the front drops
south overnight Tuesday. This will increase the chance for
showers and thunderstorms Tuesday night (40-70%). Models have
backed off a bit on the scenario of the remnants of an MCS that
develops in IA Monday evening and dropping through the area,
therefore chances are now 15-20% for showers and thunderstorms
during the day Tuesday.

The SPC did introduce a Marginal (1 of 5) Risk for severe
weather north of I-44. Machine learning models are also hinting
at this area with a 15% risk. This is supported by NBM mean
MUCAPE values staying in the 750-1250 J/kg range overnight with
deep layer shear around 20 kts. The further south you go, the
further you move away from stronger upper-level flow, and
therefore the lower the shear values are. This will limit severe
potential to north of I-44 where shear will be better. Due to
generally weaker shear and the overnight nature of our threat,
only isolated instances of wind gusts up to 60 mph and hail up
to quarters at the max are expected.


Daily Heat Indexes in the 90s and 100s through the week:

Before the rain arrives, highs Tuesday will continue to be in
the mid-90s with lows in the lower 70s. Heat Index values will
be in the 100-105 F range with some isolated areas above 105 F.
Therefore, another Heat Advisory for Tuesday may be issued, but
the slight cooling trend is keeping us from issuing with this
forecast package.

After the cold front drops through Tuesday night, global
ensembles are actually trending a tad "cooler" for Wednesday and
Thursday. By "cooler", that means highs in the upper 80s (lower
90s along the MO/AR and MO/KS/OK borders) and lows in the middle
to upper 60s, which is more seasonable for this time of year.

This will be short-lived as the upper-level high translates back
east, allowing highs to heat back up into the 90s for the
weekend. Lows into the weekend will also warm back up to the
lower to middle 70s. Nevertheless, Heat Index values will
continue to range in the 90s to the 100s during the whole week
(generally 100s building back into the weekend). Heat safety
listed in the Short Term section should continue to be exercised
during the week.


Next system arrives next weekend:

Rain chances have slightly increased to 30-50% next weekend as
models come into more agreement of a potent and deeper shortwave
trough traversing the northern Plains with an associated cold
front diving through. Chances exist Friday night through Sunday
morning, however, the trough/front is expected to be more
progressive/quicker than that. There are just model differences
in the timing of the front (GEFS brings the front through Friday
night/Saturday morning while the EPS brings it through Saturday
afternoon into Sunday morning). This makes NBM chances modest
for an extended period. The highest chances exist where the two
overlap Saturday night into Sunday morning. The main message to
take away here is that a round of precipitation is becoming
increasingly likely sometime this weekend.
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&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1240 PM CDT Sun Jun 23 2024

VFR conditions will prevail through the entire TAF period at all
TAF sites. A frontal boundary is lingering around the area and
will provide light and variable winds as it lifts back north
throughout the period. Winds will settle on S`ly at 5-10 kts by
14Z. Otherwise, high clouds will remain scattered. A cumulus
field has developed near BBG along the front is back-building
into SGF and JLN and will linger there for the 19-00Z
timeframe. These will stay above 4 kft, however.

&&

.CLIMATE...
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Issued at 200 PM CDT Sun Jun 22 2024


Record High Temperatures:

June 23:
KJLN: 98/2009

June 24:
KSGF: 99/1988
KJLN: 100/1954
KVIH: 99/1901


Record High Minimum Temperatures:

June 23:
KSGF: 77/2015

June 25:
KSGF: 76/1952

June 26:
KSGF: 76/1937

June 29:
KSGF: 80/1936
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&&

.SGF WATCHES/WARNINGS/ADVISORIES...
KS...Heat Advisory from noon to 8 PM CDT Monday for KSZ073-097-101.
MO...Heat Advisory from noon to 8 PM CDT Monday for MOZ055>058-
     066>071-077>083-088>098-101>106.

&&

$$

SHORT TERM...Price
LONG TERM...Price
AVIATION...Price
CLIMATE...Price