171
FXUS63 KSGF 051141
AFDSGF

Area Forecast Discussion
National Weather Service Springfield MO
641 AM CDT Sun Oct 5 2025

.KEY MESSAGES...

- Above normal temperatures continue through the early week.

- 20-50% chances of showers and thunderstorms across the area
  Monday through Tuesday. 30-50% chance for greater than half an
  inch of rain in locations east of Highway 5.

- Slightly cooler temperatures behind a front mid-week with more
  normal temperatures. Confidence is increasing in persistent
  above normal temperatures returning late week.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 300 AM CDT Sun Oct 5 2025

The synoptic pattern across our area has narily changed over the
past 24-48 hours as a positively tilted shortwave ridge axis
still protrudes through southern MO beneath a larger-scale ridge
across the entire eastern half of the CONUS. Very dry mid-level
air is nosing into southern MO as noted on water vapor imagery
within the shortwave ridge axis. That being said, the pattern
over the western half of the CONUS has changed a bit with a
deep and moisture-laden longwave trough over the entire west
CONUS, with a compact shortwave ejecting off the Rockies into
the Dakotas. A surface low is noted in ND beneath the compact
shortwave. A surface high is still situated over the east
CONUS, slowly shifting eastward. The resulting pressure gradient
in the space between has increased south-southeasterly winds
across the central Plains. Winds yesterday were observed at
10-15 mph with gusts up to 20-25 mph. Observations overnight are
in the 8-12 mph range. Increased winds will continue to keep
lows a bit more mild this morning in the middle 50s to lower
60s.


Above normal temperatures and dry, breezy weather continue today:

With the pattern over our area barely changing over the last 24
hours, the forecast for today looks like a repeat of yesterday.
Temperatures will continue to be 10-15 degrees above normal in
the lower to middle 80s. The main change is slightly higher
wind speeds across the area as the surface pressure gradient
tightens a bit more with the slight eastward progression of the
jet stream. Expect wind speeds between 12-18 mph with gusts up
to 20-25 mph at times again today. Slightly increased moisture
from southerly advection should keep minimum relative humidity
values above 30-35% in most places, though increased winds and
very dry mid-level air may result in some localized areas below
30% again today presenting a very minor and localized fire
weather risk. Lows tonight then remain in the lower 60s.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
Issued at 300 AM CDT Sun Oct 5 2025

20-50% chances of showers and thunderstorms Monday and Tuesday:

After the aforementioned shortwave trough surges north into
Canada, the resulting upper-level pattern is an extensive
positively-tilted trough from CA up into central Canada with the
jet stream oriented along and just east of that axis. The
positively-tilted nature of the trough will keep the jet stream
stalled in this position through Tuesday, only slowly shifting
east with the longwave. This sets up the baroclinic zone and
resulting cold front in a line from the TX/OK panhandles NE into
the northern Great Lakes. As a result, much of the precipitation
along this stalled front should stay north and west of our CWA
Monday.

Meanwhile, though, models show a subtropical branch of the jet
stream impinging the Ozarks Monday into Monday night. This
occurs as subtle mid-level shortwave energy lifts out of the
Gulf along the Mississippi River Valley. As a result, better
surface moisture and weak instability will advect into southern
Missouri which will combine with lift from the mid-level
shortwave energy, and upper-level ascent from the subtropical
jet. All these combined should force scattered showers and
thunderstorms across the area Monday into Monday night (20-50%
chance).

The mid-level shortwave will exit eastward Tuesday, but at this
point, the cold front and polar shortwave trough will slowly
traverse the region, bringing additional 20-40% chances for
showers and thunderstorms Tuesday.


Highest rainfall amounts are forecast to be east of Highway 5:

For the most part, showers and thunderstorms are expected to be
isolated to scattered across most of the region Monday and
Tuesday. However, greater lift and more widespread rain and
thunderstorms can be expected where the nose of the subtropical
jet overlaps with the northward progressing mid-level positive
vorticity advection. This appears to be along the Mississippi
River Valley. Therefore, much of this higher coverage should
stay east of the area, but medium-range guidance from the SREF
gives a 30-50% chance for some of this greater coverage to enter
our region, mainly east of Highway 5. Here, widespread amounts
of 0.25-0.75" are possible as shown by the REFS blended mean,
with NBM and SREF guidance giving a 30-50% chance of greater
than half an inch of rain east of Highway 5 through Tuesday.


Slightly cooler temperatures behind cold front mid-week:

Temperatures are expected to slightly cool to near normal as the
front moves through Tuesday and Wednesday. With the front
expected to be across east KS/west MO Tuesday, a gradient of
high temperatures from the lower 70s across central MO and east
KS, to the lower 80s along the MO/AR border are forecast. Highs
Wednesday after the front has fully cleared should be a bit
cooler in the middle 70s. Lows Tuesday and Wednesday night will
range across the 50s.


Confidence increasing in above normal temperatures returning:

In previous forecast discussions, we were talking about the two
scenarios of fall-like temperatures remaining following the
front, or above normal temperatures returning. As we draw closer
to the timeframe, ensembles are starting to favor above normal
temperatures quickly returning as deep synoptic-scale ridging
and southerly surface winds are progged to rebuild across the
west-central CONUS. Confidence is increasing in this scenario
as NBM spreads continue to tighten toward the upper end of the
range and LREF guidance continues to drop cooler members one by
one. Additionally, the Extreme Forecast Index continues to
increase values for late this week, with even a shift of the
tail. NBM 75th percentile max temperatures for Springfield are
near 90 F for late this week. Those two pieces of guidance
combined suggest there is a chance (albeit low for now) for
record high temperatures to be challenged late this week.

Additional chances for rain, however, are stil quite uncertain
based on the position of the upper-level ridge. A further west
ridge (favored by most of the GEFS members) would allow
shortwaves to traverse the region, bringing some rain chances. A
further east ridge with the axis across our region (favored by
most of the ENS members) would hinder any rain chances.

The returning above normal temperatures are then expected to
persist as the CPC gives a quite high confidence forecast
(70-80% chance) for above normal temperatures between the
October 10th to 18th timeframe.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 640 AM CDT Sun Oct 5 2025

VFR but breezy conditions are expected through the TAF period
with clear skies. South-southeasterly winds will be at 10-15 kts
for much of the period after 13Z. Some gusts up to 20-25 kts
are possible at times, especially between 14-23Z.

&&

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

&&

$$

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