319
FXUS63 KSGF 160511
AFDSGF

Area Forecast Discussion
National Weather Service Springfield MO
1211 AM CDT Mon Jun 16 2025

.KEY MESSAGES...

- On and off chances (30-80%) for showers and thunderstorms
  today and tonight as a weak slow-moving system traverses the
  area. Isolated and localized instances of gusty winds and
  flooding are possible.

- 15-40% chances of leftover scattered showers and
  thunderstorms east of Highway 65 Monday.

- Marginal (1 of 5) Risk for severe thunderstorms Tuesday night
  across central Missouri, then a Slight (15% Chance) Risk
  Wednesday for much of our forecast area.

- Humid conditions are expected through the coming week.
  Signals point to temperatures nearing 90 F towards the end of
  the week. Therefore, we may see heat index values in the
  mid-90s to around 100 at times.

&&

.SHORT TERM /THROUGH TUESDAY/...
Issued at 245 PM CDT Sun Jun 15 2025

The current state of the atmosphere depicts large-scale ridging
across the entire CONUS as the jet stream remains situated
along the US/Canada border. Trapped beneath the ridge are two
weak MCV-type shortwaves. One is located across the
Appalachians, with the other smack-dab overtop southwestern
Missouri. The large-scale ridging is allowing for an expansive
warm and very moist airmass across the entire central and
eastern CONUS with dewpoints above 70 F and highs in the 80s--
although cloud cover today should keep highs in the middle to
upper 70s. The lift from the weak MCVs the past few days has
allowed for multiple days of slow-moving showers and
thunderstorms. At the apex of the MCV where a pseud-boundary is
present, several rounds of training heavy rainfall has already
occurred, prompting some areal and flash flood warnings across
west Missouri and extreme Southeast Kansas. That same story
continues today into Monday as the MCV slowly translates
eastward through the region.


30-80% chances for on and off showers and thunderstorms:

Daytime heating has allowed the start of greater coverage of
showers and thunderstorms east of the MCV, along and east of the
Highway 65 corridor. This corridor (south of a St. Clair to
Maries County line) will be the focus for on and off chances for
showers and thunderstorms through tonight (50-80% chance). North
of here, parallel to a Vernon to Phelps county line is where a
pseudo-deformation zone has developed. Light to moderate rain
should occur along this corridor through today and tonight.

The 12Z sounding depicted PWATS around 1.79" which is just shy
of the average record PWAT for mid-June according to the SPC
Sounding Climatology page. Needless to say, that`s quite a lot
of moisture, with saturated profiles throughout the atmosphere
and 500-1000 J/kg of long-skinny CAPE. Therefore, any stronger
shower/thunderstorm will carry the potential for localized
flooding, especially if multiple train over the same area.
Within the bands of heavier precipitation this morning, we have
seen rain rates up to 3 inches per hour. Any flooding will be
very localized and confined to one spot, but any given location
will carry that risk today and tonight if multiple storms are
experienced.

Lastly, this is a very low-end threat, but the MCV has modulated
shear profiles a bit east of Highway 65. Our VAD has shown hints
of 25-30 kts deep layer shear with small but curved hodographs.
1000-2000 J/kg of tall-skinny CAPE has developed east of Highway
65, and with weak storm-relative inflow of 15 kts, mini
supercells are possible. Indeed, a couple storms out there have
shown some weak rotation and spinny structures. Therefore, gusty
winds and a very low-end scenario of a weak spin-up tornado is
possible, though low-level shear is still weak.


15-40% chances for leftover scattered showers Monday:

Models have trended a bit more progressive with this system,
leading to the highest chances for showers and thunderstorms to
be confined to the eastern Ozarks Monday (15-40% chances). The
same story as for today can be said for the eastern Ozarks
tomorrow: On and off showers and thunderstorms with the
potential for localized flooding.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
Issued at 245 PM CDT Sun Jun 15 2025

Marginal (1 of 5) Risk for severe thunderstorms Tuesday night:

A slight pattern change is in store Tuesday and Wednesday as a
modest trough is progged to extend into the central Plains as it
traverses from west to east. Global models are coming into
better agreement on trough shape, though there are still some
uncertainties in the intensity. Either way, models are more
certain in an attendant surface cold front moving through the
northern Plains Tuesday, and our area Wednesday. The
introduction of the trough will increase deep-layer shear
overtop of our muggy air mass in place. As such, severe
thunderstorms are possible along the surface cold front.
Tuesday, this would be over the northern Plains, in which the
remnants of the complex may reach our area from the north
Tuesday night. The main question is how far south the MCS will
make it before dissipating. Early CAM signals generally agree
with the extent of SPC`s Marginal (1 of 5) Risk, which is along
and just south of the I-44 corridor. Being a remnant MCS
overnight, damaging wind gusts and large hail will be the
primary hazards.


Slight (15% Chance) Risk for severe thunderstorms Wednesday:

The better severe risk for our area comes Wednesday into
Wednesday night as the cold front is forecast to move through
the area. There are still some uncertainties in the exact type
of storm mode since global ensemble hodographs show just modest
deep layer shear (30-35 kts) which would be very borderline for
supercells. This would still be sufficient for damaging winds
and large hail from line segments and/or a developing MCS.
However, given a >25+ kt LLJ expected, if supercells were
possible, tornadoes would be an added risk as the environment
will have reached necessary ingredients given curved hodographs
(despite the stunted shape) showing 100-200 m2/s2 0-1 km SRH and
15-25 kts 0-1 km bulk shear from NAM and GFS deterministic
soundings. If an MCS and/or line segments are the dominant mode,
tornadoes would be much less of a threat since 0-3 km bulk shear
vectors will be oriented parallel to the front/modeled line
orientation.


Above normal temperatures and muggy conditions through the week:

NBM dewpoints are forecast to be quite high through next week,
with the mean at mid-70s dewpoints as far out as next Sunday.
This makes sense as both NAEFS and ECMWF ESATs show >97.5th
percentile mean specific humidity everyday through June 24th
(with some days at the Max for the 30-year climatology for mid-
June). Additionally, behind the exiting trough, ensembles are in
agreement with a deep ridge building into the area, which
should allow highs to reach the upper 80s and lower 90s,
especially toward the weekend. While ensembles are in agreement
in a large-scale ridge, there are still some uncertainties in
how deep the ridge builds. Cluster analysis shows a 40% scenario
where the ridge is deeper, which would increase forecasted high
temperatures. Currently the operational NBM has highs in the
lower 90s Friday and Saturday, but the experimental new NBM
build is outputting middle to upper 80s. It will be interesting
to see which scenario pans out.

Lows toward the weekend are also forecast to reach the lower to
middle 70s. Therefore, a heat risk will begin to increase. Mean
NBM heat index values reach the middle 90s to lower 100s after
Thursday. With multiple days of abnormal humidity, above normal
temperatures, little heat relief at night, and it being the
first heat stretch of the year, the HeatRisk reaches a Major (3
of 4) level by Saturday. We will have to monitor trends for any
potential increases in concern with the heat forecast. But at
least it won`t be raining anymore.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1207 AM CDT Mon Jun 16 2025

For the 06z TAFS, low level moisture remains fairly high across
the area and we`ll likely see MVFR and IFR conditions overnight
into Monday morning. Most of the showery activity associated
with the MCV should remain east of the area, although a narrow
band of showers may affect SGF with a brief shower at the onset
of the TAFS and have thrown in a prob30 group for the initial 3
hours. We should start to clear out late in the day and Monday
evening but may need to watch for fog once again developing
Monday night.

&&

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

&&

$$

SHORT TERM...Price
LONG TERM...Price
AVIATION...Lindenberg