mo discuss
Office: LSX
FXUS63 KLSX 221715
AFDLSX
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1215 PM CDT Wed Oct 22 2025
.KEY MESSAGES...
- The combination of gusty northwest winds, low humidity, and dry fuels
will yield elevated fire danger in northeast Missouri and west-
central Illinois this afternoon.
- Seasonably cool and dry conditions will persist through
Thursday. Areas of frost are forecast both tonight and Thursday
night for portions of the area.
- Light rain chances (40-60%) return on Friday into the weekend,
mainly in parts of central and southeast Missouri. The chances
for more significant (0.50"+) rainfall have decreased
considerably.
&&
.SHORT TERM... (Through Late Tonight)
Issued at 253 AM CDT Wed Oct 22 2025
Another seasonably cool and dry day is on tap along with plenty
of sunshine. Northwest winds will be lighter as a surface ridge of
high pressure moves eastward into western Missouri by this
afternoon. Winds will still be a bit gusty though today,
especially in eastern Missouri over into Illinois. Gusts of 25-30
mph are expected in these locations. The combination of these
gusty northwest winds, low relative humidity values, and dry fuels
will yield elevated fire danger this afternoon across much of
northeast Missouri and west- central Illinois.
The surface ridge is expected to move to near the Mississippi River
late tonight. This should allow winds to go light/variable over the
bi-state area. Light winds, a clear sky, and seasonably low
dewpoints are expected to yield a chilly night with lows mainly in
the mid to upper 30s. Areas of frost are expected in areas that do
drop into the mid 30s. The best chances (30-40%) for lows at or
below 36 degrees occurring from the latest HREF are in northeast
Missouri and west-central Illinois. Some river valleys in central,
east central, and southeast Missouri also are more liable to see
temperatures drop into the mid 30s and observe frost development.
Temperatures still do not look quite cold enough over a large enough
area for widespread frost. Therefore, still no plans for issuing a
frost advisory. Climatologically speaking, we are also now about 7-
10+ days late for observing a first frost. That combined with most
vegetation already in largely a dormant state due to ongoing drought
conditions suggests any impacts from frost should be very minimal as
well.
Gosselin
&&
.LONG TERM... (Thursday through Tuesday)
Issued at 253 AM CDT Wed Oct 22 2025
(Thursday - Thursday Night)
The surface ridge will be very slow to move eastward, so a
continuation of the seasonably cool and dry conditions will continue
through Thursday night. Temperatures will be very near persistence,
with highs mostly in the low to mid 60s. Lows Thursday night are
expected to range from the mid 30s (south-central Illinois) to low
40s (central/southeast Missouri). Coolest locations in south-central
Illinois will be prone for areas of frost once again. Temperatures
warm as you head west due to increasing easterly surface winds.
(Friday - Saturday Night)
Model guidance has made some significant changes with respect to our
rain chances associated with a closed midlevel low moving into the
south-central Plains. For one, mid/upper level troughing across the
Great Lakes/Ohio Valley is stronger than modeled 24 hours ago. This
in turn leaves more confluence across the mid-Mississippi Valley
downstream of the closed low exiting the Rockies into the south-
central Plains. An overall weaker midlevel system tracking a bit
further south is the end result, which shifts the higher rainfall
chances (and the more significant amounts) further southwest as
well. Probabilities on the LREF for at least 0.50" are now in the 20-
50% range along/south of I-70 in Missouri. That is about about a
50%! drop compared to 24 hours ago. Another problem is that this
system will be fighting persistent dry low-level southeasterly flow.
This long fetch will continue to advect in low dewpoints into the
region (upper 30s to low 40s). Low-level dry air can certainly be
overcome, but needs strong enough forcing for ascent over a long
enough period of time, which seems questionable especially the
further north and east you go. That still may occur late Friday-
Saturday night, mainly across central/southeast Missouri.
Deterministic models show increasing low-level moisture advection
concurrently with weak upper-level jet support and mid/upper level
diffluence ahead of the closed low. While PoPs are still fairly high
(40-60%) in central/southeast Missouri, any rain looks light. The
LREF probabilities for more than 0.25" are between 50-60% in these
same locations. While any rainfall is beneficial given the ongoing
drought, it appears the prospects for widespread significant
rainfall have dwindled considerably.
Seasonably cool high temperatures should continue through Saturday.
While rain chances have decreased, there remains a strong signal for
thick mid/upper level cloud cover over the area. Low temperatures
will moderate though due to the aforementioned increase in clouds.
Lows are forecast to be in the 40s to low 50s Friday and Saturday
night.
(Sunday - Sunday Night)
Uncertainty increases late this weekend with how the closed midlevel
low evolves. There is quite a bit of spread, with some members of
the LREF weakening the low and shunting it south. This scenario
would likely mean most of the area would be dry Sunday/Sunday night.
Other members take the closed low northward more into the mid-
Mississippi Valley. If this scenario occurs, most of the area would
at least see some rainfall during this time period. Given the
uncertainty and model spread, the NBM PoPs of 20-40% from north to
south seemed reasonable at this time.
(Monday - Tuesday)
Ensemble spread is very high for early next week with respect to the
evolution of a strong midlevel shortwave trough moving across the
Plains. This system should lead to a cold frontal passage sometime
early next week, but any other details are largely unknown at this
forecast range. The frontal passage itself should bring a good
chance of rain, but how widespread and how much are big question
marks. LREF probabilities over a 24-hour period ending Tuesday
afternoon are 60-70% for measurable rainfall. While there is a
scenario for a dynamic system characterized by a negatively tilted
midlevel shortwave trough and surface cyclogenesis across the mid-
Missouri Valley, even in this scenario instability really looks
meager. Low-level moisture return looks to be an issue with
troughing across the southeastern CONUS. In addition, plenty of
clouds early next week look to keep highs mainly in the 60s.
Probabilities for >100 J/kg of SBCAPE on the GEFS/GEPS stay below
50% areawide through Tuesday. Therefore, elected to keep thunder out
of the forecast for now.
Gosselin
&&
.AVIATION... (For the 18z TAFs through 18z Thursday Afternoon)
Issued at 1212 PM CDT Wed Oct 22 2025
Gusty northwest winds will gradually shift eastward today with a
few gusts of 20-25 knots, mainly running from KUIN southward
through the metro terminals. Winds subside tonight, becoming light
and variable until mid to late morning Thursday.
VFR conditions are expected throughout the period.
Maples
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...Frost Advisory from 1 AM to 9 AM CDT Thursday for Audrain MO-
Knox MO-Lewis MO-Lincoln MO-Marion MO-Monroe MO-Pike MO-
Ralls MO-Shelby MO.
IL...Frost Advisory from 1 AM to 9 AM CDT Thursday for Adams IL-Bond
IL-Brown IL-Calhoun IL-Fayette IL-Greene IL-Jersey IL-
Macoupin IL-Marion IL-Montgomery IL-Pike IL.
&&
$$
WFO LSX
Office: SGF
FXUS63 KSGF 221741
AFDSGF
Area Forecast Discussion
National Weather Service Springfield MO
1241 PM CDT Wed Oct 22 2025
.KEY MESSAGES...
- Isolated frost potential early this morning as temps dip into
the upper 30s. Be sure to cover sensitive vegetation on
elevated surfaces.
- 60-90% chance of showers and thunderstorms Thursday night into
at least Saturday. Potential for a long-lived, but beneficial
and wetting rain with a low/marginal flooding threat at this
time.
&&
.SHORT TERM /THROUGH TONIGHT/...
Issued at 245 AM CDT Wed Oct 22 2025
Current Conditions and Synoptic Pattern: Water vapor and upper
air analysis shows a northwest flow pattern across most of the
northern and central US. This has allowed for a cooler and drier
airmass to remain across the area. The 00z KSGF sounding was
extremely dry with only a 0.26in PW value. A surface high
pressure axis was located from Nebraska down into Oklahoma with
clear skies and light west winds across the area. Temps have
already dropped into the upper 30s to lower 40s across most of
the area early this morning.
Today: Temps will likely start around the mid/upper 30s to lower
40s by sunrise. Would expect some patch frost in the colder
valleys however not expecting widespread frost this morning.
Consensus of high res models is that it will be another clear
sky day. High temps will likely be a few degrees warmer as 850mb
temps warm slightly. The airmass will remain dry and while we
are expecting RH values to again drop into the 20-25% range,
winds will be much lighter than the last two days which will
limit the fire danger.
Tonight: The surface high pressure axis will begin to slowly
move east of the area however another night of lows in the
mid/upper 30s in the valleys and lower 40s across the rest of
the area. Therefore some areas east of Springfield may see
patchy frost but nothing widespread is expected.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
Issued at 245 AM CDT Wed Oct 22 2025
Thursday: Upper level shortwave energy will move through the
southwest US with mid level ridging developing just west of the
area. Winds look to begin turning more southeasterly with
warming 850mb temps. The NBM supports highs in the upper 60s to
lower 70s with increasing high clouds through the day but the
area will likely remain dry.
Thursday night through Sunday: Ensembles continue to be in
decent agreement that a low level jet will develop Thursday
night and nose into the area. Increasing moisture and lift will
act to develop showers and isolated thunderstorms across Kansas
and Oklahoma which will move into the area by Friday morning.
Friday is shaping up to be a cloudy, rainy and cool day with
the NBM showing highs remaining in the 50s. Precip chances are
in the 50-80% range for Friday. Instability looks to remain
mainly west of Highway 65 therefore the thunderstorm potential
is low across most of the area.
The upper low looks to move slowly east/southeast on Saturday
with a continued threat for showers and isolated thunderstorms,
especially across the southwest half of the area. The main
difference currently is with the ejection of the upper low
Sunday as there are timing differences which will determine if
the precip lingers through the day Sunday. Overall rainfall
amount potential Thursday night through Sunday from the NBM
conveys a 40-70% chance of rainfall amounts of 1 inch or more
from Springfield and points southwest with much lower probs
northeast of Springfield. Rainfall probs of 2 inches or more
remain less than 30% southwest of Springfield. The EFI Shift of
Tails for excessive rainfall/qpf really highlights area
southwest of the area (Oklahoma) for any anonymously high
rainfall potential. Therefore the flooding risk looks very
low/marginal at this time. Given the low instability the
lightning risk may be confined to areas west of Highway 65.
Monday and Tuesday: Ensembles then show a negatively tilted
upper trough early next week. This could force additional
precip chances with perhaps increased thunderstorm potential
however uncertainties in structure, timing and moisture levels
all keep precip chances in the 20-30% range at this time.
&&
.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1240 PM CDT Wed Oct 22 2025
VFR conditions to prevail at all TAF sites through the entire
period. Winds will generally be at 3-10 kts and changing
direction several times through the period as surface boundaries
hover around the area.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
KS...None.
MO...None.
&&
$$
SHORT TERM...Burchfield
LONG TERM...Burchfield
AVIATION...Price
Office: EAX
FXUS63 KEAX 221720
AFDEAX
Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1220 PM CDT Wed Oct 22 2025
.KEY MESSAGES...
- Chilly morning lows today and thursday lead to areas of frost.
Sensitive vegetation will need to be protected.
- Rain chances continue later this week but a southward trend
continues.
&&
.DISCUSSION...
Issued at 312 AM CDT Wed Oct 22 2025
Eastern KS and western MO reside in weakened surface pressure zone
that looks like an elongated pressure col that extends from the
Arklatex into eastern MT. With weak winds and very dry dewpoint
temperatures, most of Tuesday's low temperatures occurred just
prior to midnight. This portends to very chilly morning lows in
the in the mid 30s for most (the exception being the urban and
suburban areas of KC) and some areas in northwestern MO/ extreme
NE KS dropping into the lower 30s. Similar conditions, shifted
slightly eastward with the eastward shift in the surface high,
will exist Thursday morning. After much collaboration with
neighbors, will issue an advisory for the probable areas of
northern MO. This may need to be expanded southward and
particularly southeastward to the vicinity of the Missouri
River.
For the precipitation chances late this week into the weekend, the
southward trend continues. The leading mid-level shortwave looks
weaker, with a the best moisture transport focused from southern KS
into southwestern MO, the heaviest rain will with the initial mid-
level wave should stay to our south Thursday night into Friday
morning. As the larger-scale trough begins to move into the Central
Plains, the northern warm front lifts northward into northeastern KS
through central MO. This will result in scattered to possibly
widespread showers and a few thunderstorms through day Friday. The
best chances continue to be along and south of I-70. As this trough
shifts east, it detaches from the upper flow and becomes a
closed low that meanders eastward through remainder of the
weekend. This will lead to continued scattered showers and a few
thunderstorms, particularly as the cold core moves over the
region Sunday/ Sunday night. As this is occurring, another,
potentially stronger trough, dives into the Central Plains. The
deterministic GFS shows a very strong system moving through the
area with strongly diffluent upper flow and surface dewpoints
surging into the lower 60s Monday afternoon which leads to
decent MUCAPE for late October. If this trend continues we would
have potential for severe weather. However, the deterministic
ECMWF, while still showing a trough moving into the middle of
the country, is weaker, further south, and overall much less
robust. Ensemble guidance leans closer to the ECMWF with this
system with this suite of guidance. So we'll need to watch how
this system evolves but for now, a trend toward a weaker system
is the more probable route.
&&
.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1218 PM CDT Wed Oct 22 2025
VFR conditions anticipated for the duration of the TAF period. Winds
around 5-10 kts out of the southwest will persist until this
evening. Once we lose daytime heating, winds will become light
and variable.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...Frost Advisory from 2 AM to 9 AM CDT Thursday for MOZ001>008-
011>017-022>024.
KS...None.
&&
$$
DISCUSSION...CDB
AVIATION...Collier
