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987
FXUS63 KSGF 222015
AFDSGF

Area Forecast Discussion
National Weather Service Springfield MO
315 PM CDT Sat Jun 22 2024

.KEY MESSAGES...

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- Weak frontal passage featuring scattered shower and
  thunderstorm chances (15 to 40%) tonight into Sunday morning.
  Highest chances across central Missouri.

- Warming trend ahead through Monday with highs in the 90s all.
  Humidity on the increase with heat index values between 100
  to 110 by late weekend into early next week.

- Scattered thunderstorm chances on Tuesday afternoon into
  Wednesday, with highest chances (40 to 60%) late Tuesday
  night.
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&&

.SHORT TERM /THROUGH MONDAY NIGHT/...
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Issued at 315 PM CDT Sat Jun 22 2024

An upper-level high is continuing its retrograde westward,
currently centering itself over the OklaTex region. A shortwave
trough is progressing eastward across the northern Plains. In
between these two features is an area of enhanced mid- and
upper-level SW`ly flow across NE/IA. Mid-level water vapor
imagery depicts a stream of Pacific moisture in this region. The
shortwave is forcing surface cyclogenesis in IA with an
attendant cold front stretching to the SW through NE/KS and a
warm front draped eastward across the Great Lakes.


Highs in the 90s and Heat Indexes between 95-110 F through Monday:

Winds have picked up today as the surface mass response vacuums
in air from the south. Current obs have our winds at 10-20 mph
with periodic gusts up to 20-25 mph, especially toward Joplin.
Despite the winds, temperatures are slightly overachieving the
forecast, but are still expected to peak in the lower to mid 90s
this afternoon. Heat Indexes will approach 100, but winds will
keep the Wet Bulb Globe Temperatures and associated heat risk
down just a tad. Winds will stay fairly moderate overnight,
especially on the Plateau (8-12 mph), keeping lows very mild in
the mid-70s. This will limit heat relief going into a continued
warming trend through Monday.

Despite a cold front forecast to drop through the region, it
will be a weak one and generally diffuse. On top of that, an 850
mb ridge will translate into the region Sunday afternoon with
21-24 C 850 mb temperatures advecting in. This will generally
bring hotter temperatures, especially near the MO/AR border
where the cold front may be just north of. Highs will range from
90-97 with the higher temperatures near the MO/AR border.
Associated Heat Indexes will be in the 95-105 F range. The
southern counties will be right on the edge, if not just over,
Heat Advisory criteria (105 F Heat Index). This is not expected
to be widespread areas above 105 F, so for now have held off on
a Heat Advisory. However, one may be issued later tonight if the
need is there. For now, be consious of the heat forecast to be
in place. Lows will then be mild again with temperatures in the
upper 60s in the eastern Ozarks, to the mid-70s along the
MO/KS/OK border.

Monday appears to be the hottest day of the forecast period.
Firstly, the frontal boundary is forecast to lift back north as
a warm front due to a strengthening surface low in Canada.
Secondly, the upper-level high will continue to sit in place.
Lastly, the 850 mb ridge will continue to build with
temperatures reaching 23-26 C. As such, highs will continue to
get hotter Monday, with highs at 95-100 F. Some locations
around the Ava to Branson area are given a 40-60% chance of
temperatures reaching above 100 F. These temperatures paired
with low-70s dewpoints will bring maximum Heat Indexes into the
103-110 range across our area. This will be Heat Advisory
criteria, so watch for an issuance later this weekend as
confidence builds. Lows Monday night will also be mild in the
middle to upper 70s, some places even possibly being near 80 F
toward the MO/KS border. These are near record high minimum
temperatures and are approaching a normal high temperature for
early summer. All these factors will contribute to a Moderate (3
of 4) to Extreme (4 of 4) HeatRisk (Experimental). Therefore,
it is of utmost importance to practice heat safety by checking
on family members, keeping cool in air conditioned places,
staying hydrated even if not feeling thirsty, and taking
frequent breaks if working outside for extended periods of time.


15-40% chance for showers and thunderstorms tonight into Sunday:

As the cold front sags through the area tonight, there is a
low-end chance for showers and thunderstorms to develop along
it. However, the tail-end of the cold front will be over our
region, and it will be gradually weakening with surface
deformation and associated frontolysis becoming dominant. This
will keep convergence low, making it difficult for parcels to
rise above the nocturnal inversion. Even if some parcels are
able to rise above the inversion, MUCAPE values are limited at
500-750 J/kg. As such, there is only 15-40% chances across our
CWA with the 30-40% chances across our far NE counties toward
central MO where frontal forcing is stronger.

If showers and thunderstorms are to form, west-central MO will
be impacted between 10PM-3AM, central MO will be impacted
between 12-5AM, and south-central MO impacted between 3-8 AM.
The far southwest corner of MO is expected to stay completely
dry.
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&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
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Issued at 315 PM CDT Sat Jun 22 2024

40-60% chances of thunderstorms Tuesday into Wednesday:

Our next chances for rain come Tuesday into Wednesday. A potent
shortwave trough over Canada will force a stronger cold front
to dive south through the Midwest and Central Plains. The
southward dive will be aided by a weak surface low and shortwave
dropping SE through MO at the same time. With the continued hot
and humid airmass in place, showers and thunderstorms will be
possible, especially overnight Tuesday when the front is
forecast to push through (40-60% chance). Some global models,
including members of the ECMWF, are hinting at an MCS developing
over IA Monday night and diving south into MO. This would bring
rain chances during the day Tuesday as well, but confidence
this far out is low. However, the NBM has introduced 30% chances
across the area for this scenario before the frontal passage
Tuesday night.

With these storm chances, there is mention from the SPC of a
potential severe risk. However, confidence is quite low as the
cold front is expected to escape the stronger flow aloft up in
the northern CONUS. As such, deep layer shear is forecast only
to be around 20 kts by all ensemble members. But with
instability expected to be moderate to moderate-high, 20 kts
could be enough for isolated severe multicellular clusters.
This will be further evaluated in later forecasts.


Heat continues next week with Heat Indexes at or above 100 F:

During the course of next week, the upper-level high is forecast
to slowly translate back east as upper-level flow and vorticity
picks up. This means that the ridge will once again move through
our region during the course of the week. As such, heat and
humidity will continue. Highs will be in the lower to middle
90s, Heat Indexes will be between 95-105 F making multiple Heat
Advisory days a possibility, and lows will continue to be in the
70s. The prolonged nature of this heat could take a toll on
people, especially vulnerable populations, so make sure to
continue to practice the heat safety mentioned above.


Next system arrives next weekend (still uncertainty):

The next system looks to arrive next weekend, however there is
uncertainty in exact timing and location. Nevertheless, rain
chances may increase for this time period over the next few days.
Current chances are at 15-30%.
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&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
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Issued at 1240 PM CDT Sat Jun 22 2024

Despite medium-high confidence in VFR conditions remaining
through the TAF period, there are some low-end chances of
impactful weather over the TAF sites. A weak fropa is forecast
between 05-12Z. Ahead of the frontal passage, low-level wind
shear will increase to around 35 kts. A 10-20% chance of an
isolated shower or thunderstorm also exists during this
timeframe, though the confidence of one impacting a TAF site
directly is very low.

Additionally, SW`ly winds will be gusty through 02Z at 10-20
kts with gusts up to 20-30 kts, especially at JLN. These winds
will diminish after sunset (02Z) and slowly pivot to NW`ly by
the end of the TAF period.

Lastly, a broken blanket of mid-level clouds is currently
hanging over JLN. These are expected to dissipate by 21Z leaving
a cumulus field at 5 kft through 02Z and otherwise SCT high
clouds.
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&&

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


Record High Temperatures:

June 22:
KSGF: 96/2016

June 23:
KJLN: 98/2009

June 24:
KSGF: 99/1988
KJLN: 100/1954
KVIH: 99/1901
KUNO: 100/1952

June 25:
KSGF: 99/2012

June 28:
KJLN: 102/2012


Record High Minimum Temperatures:

June 23:
KSGF: 77/2015

June 24:
KSGF: 77/1934

June 25:
KSGF: 76/1952

June 26:
KSGF: 76/1937

June 28:
KSGF: 78/1936
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&&

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

&&

$$

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