521
FXUS63 KSGF 020830
AFDSGF

Area Forecast Discussion
National Weather Service Springfield MO
330 AM CDT Thu Oct 2 2025

.KEY MESSAGES...

- High temperatures in the mid to upper 80s (5 to 15 degrees
  above normal) and mainly dry weather expected through the end
  of the week.

- While some widely isolated showers will be possible this
  afternoon (10-15% chance across southern Missouri), the next
  main potential for rainfall is not expected until early to the
  middle of next week.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 230 AM CDT Thu Oct 2 2025

Unseasonably weak atmospheric flow is apparent across much of
the CONUS as evidenced by a relatively lackluster water vapor
satellite imagery presentation. The most apparent features are a
small and weak upper-level trough traversing west to east
across IA/MO, and a subtle mid-level boundary parallel to the
Lower Mississippi River Valley with a weak stream of moisture
west of it across our area. The latter feature is known as a
backdoor (or westward moving) frontal boundary. Moisture is
noted to be higher ahead of this boundary, slowly sneaking into
our area from the east as evidenced by cloud formation across
the eastern Ozarks. The slight increase in moisture is allowing
for a bit more mild lows tonight in the lower 60s with sparse
areas of light ground fog, especially in low-lying areas.

Despite the subtle features around the area, due to the larger
scale weak flow and ridging pattern in place, much of the area
is expected to be mostly sunny today with highs in the middle to
upper 80s again.


10-15% chance for a stray shower or thunderstorm this afternoon:

The backdoor front along with the slight increase in moisture
ahead of it will be the focus for a very low chance (10-15%) for
a stray shower or thunderstorm across southern MO. The gradual
moistening of our atmospheric profile as shown by our balloon
data the past few days will allow for 500-1000 J/kg MLCAPE
today, according to short-term ensemble guidance. While
moistening has been occurring, there`s still an appreciable
amount of dry air in the mid and upper levels. As a result,
model soundings show these MLCAPE profiles to be rather skinny
and short, which would result in short, stout, and weak showers
and thunderstorms if any form.

The question on if storms form will be a matter of balance
between convergence/lift along the backdoor front and subsidence
within the backside of the weak upper-level trough which is
forecast to overlap the greatest instability corridor at peak
heating. For this reason, chances are low (10-15%) for a stray
shower or thunderstorm to pop-up across southern MO this
afternoon, generally between 3-7 PM. If any do form, no hazards
are expected except for maybe a few lightning strikes.

The chance of rain out there can also be explained in this way:
There`s 50-70% confidence in a stray shower developing somewhere
across southern Missouri (SREF 24-hour precip guidance), but
only a few square miles (<5% of the area) would see rain. If any
place does see rain this afternoon, it would be akin to winning
a sort of lottery.

Anyways, temperatures are then expected to be mild again tonight
in the upper 50s to middle 60s.


&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Issued at 230 AM CDT Thu Oct 2 2025

Above normal temperatures and dry weather through the weekend:

The subtle features of today will depart Friday, making room for
another day of weak flow and above normal temperatures in the
upper 80s. Over the weekend, atmospheric flow starts to
increase as a potent shortwave trough ejects off the Rocky
Mountains to the NNE. The shortwave trough ejection will force
a surface low pressure system over the Northern Plains, and
tighten the pressure gradient across the central Plains, which
will increase southerly winds across our area Saturday and
Sunday. Therefore, expect breezy conditions this weekend
(compared to recent days) with winds in the 10-15 mph range and
gusts up to 15-20 mph at times. Current forecasts also project
afternoon relative humidity values in the 30-40% range, though
the NBM mean has been slowly decreasing these values,
corroborating pattern recognition of a departing surface high
pressure system. This would suggest values may be a bit lower
in the 25-30% range.

Highs will continue to be in the middle to upper 80s this
weekend with lows in the middle 50s to middle 60s.


Next main chance for rain arrives early to middle of next week:

Following the shortwave trough ejection, an energetic longwave
trough is progged to situate itself over central Canada and the
northern CONUS. While this is pretty well agreed upon in global
ensembles, the timing of it, along with the progression of
shortwave energy through the central CONUS, is widely varied
within the clusters. Depending on the timing and progression of
the longwave pattern and shortwave energy matching up with a
surface cold front moving south, rain chances may increase
early next week. NBM deterministic rain chances have slightly
increased Monday and Tuesday from previous forecasts (now
15-30%, up from 10-20%), though lots of details are still to be
worked out.

As mentioned before, LREF clusters are widely varied for the
wave progression. Half of the members put us under a ridge with
either a faster/slower wave progression keeping us mostly dry,
while the other half has the trough progression occur during the
Monday/Tuesday timeframe as the cold front drops south. This
scenario would increase lift and upper-level support across our
area and increase rain chances. Unfortunately, each cluster
scenario has an even split of members from the GEFS/GEPS/ENS,
making it difficult to strip away model biases to lean toward a
favored solution. This means rain chances next week are
basically a three-sided coin flip at this point in the forecast
(hence the 30% chances).

That being said, the synoptic pattern appears to favor opening
the gulf, bringing back 60+ F dewpoints and subsequent
instability. Additionally, the deterministic GFS/ECMWF have
both favored a scenario where a subtropical jet noses into the
Ozarks Monday and Tuesday, with the right entrance region of a
polar jet streak coming close to our area. This scenario would
bring rain chances sometime Monday and Tuesday. We will continue
to monitor trends, but as NBM confidence increases in some form
of frontal passage next week, deterministic highs drop into the
middle 70s Wednesday and Thursday, though spreads increase
drastically during this period as some members show a cold front
moving through while others do not. Therefore, highs could be
anywhere from the upper 60s to the middle 80s for the middle of
next week, depending on which scenario becomes favored.


&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1240 AM CDT Thu Oct 2 2025

VFR conditions to prevail through the entire TAF period with
light 3-8 kt winds generally out of the southeast. Mostly clear
skies are expected, save for a sparse 6-7 kft cu field between
18-00Z. Some minor nuances to the aviation forecast are
discussed below.

Some light mist has been noted in observations and on satellite,
especially in lower lying areas. Therefore, there is a low
(<20%) chance for some brief drops in visibilities, especially
at BBG, between 07-13Z.

Lastly, there is also a low 15% chance for a stray shower or
thunderstorm at BBG between 20-01Z, but there is much higher
confidence in any rain chances staying east of the site.

&&

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

&&

$$

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