Oakville, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

281
FXUS63 KLSX 222340
AFDLSX

Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
540 PM CST Mon Dec 22 2025

.KEY MESSAGES...

- A warming trend continues the next few days with near record
  highs Wednesday through Saturday. An eventual cool down is
  expected this weekend.


&&

.SHORT TERM...  (Through Late Tuesday Night)
Issued at 220 PM CST Mon Dec 22 2025

Our cool surface high has moved well off to the east this afternoon,
currently over North Carolina. That`s left our area in a southerly
low level flow with a moist southwest flow just off the surface.
That`s led to warmer temperatures despite widespread cloud cover. In
fact, this morning we saw the last freezing temperatures we`ll see
for a while as the next several days continue the warming trend.
Ridging has begun to build over the Plains and we`ll see that warmth
spill into our area over the coming days. Tonight, though, the moist
low level flow continues which will keep areas of clouds around and
buoy temperatures well above freezing. If there are some breaks in
the clouds we could see some fog develop in spots, but confidence in
this occurring remains low at this time.

While the ridge continues to build on Tuesday, a trough over the
Great Lakes actually sends a cold front southward behind it, likely
reaching central Missouri to southern Illinois by late in the day
Tuesday. This has the effect of stalling or delaying the warm up a
little bit to the north of the front. South of the front a rise well
into the 60s is expected. This front will be a frequent player in
our weather over the next several days as it wobbles north and south
separating mild air to the north from near record warmth to the
south.

Kimble

&&

.LONG TERM...  (Wednesday through Next Monday)
Issued at 220 PM CST Mon Dec 22 2025

Ridging aloft continues to build east toward the Mississippi Valley
Tuesday night into Wednesday while surface high pressure shifts east
through the Great Lakes. The front that drops south on Tuesday then
lifts back north as a warm front Tuesday night into Wednesday. By
then not only will temperatures be rising to extreme levels for this
time of year, anomalous moisture will be arriving as well. Dewpoints
rise through the 50s and even into the low 60s south of the front.
Along and north of the front where the last of the "cooler" air
hangs on, the push of warm, moist air over the boundary will lead to
clouds and possibly some drizzle or fog. This potential is greatest
in the north across northern Missouri into central Illinois. South
of the front deeper mixing will allow for less cloud cover and
warmer temperatures rising potentially into the 70s for the first
time.

Somewhat new relative to recent forecasts, guidance is starting to
latch on to a subtle shortwave trough tracking around the top of the
ridge late Wednesday into Thursday. This has the effect of sloshing
the front back southward again on Thursday, potentially to a
position near I-70. Once again, temperatures north of the front will
be more limited by slightly "cooler" air and greater potential for
cloud cover, while south of the front it warms back into the 70s
again. The positioning of this front will play the key role in
whether our climate sites reach record highs for Christmas Day. The
latest NBM has fallen 5 degrees for its forecast high at St Louis on
Christmas, from 74 to 69 with this forecast. This is in spite of
advertised strong confidence in previous runs with an interquartile
range of only 4 degrees with last night`s forecast. Today that
interquartile range has risen to 11 degrees indicating greater
uncertainty regarding the positioning of that front. Among the 12Z
deterministic guidance, most major models now show the front dipping
to near or just south of St Louis, thus pushing toward the cooler
scenarios. While we say cooler, it`s worth noting that it will still
be 20+ degrees above normal even if the front is able to bring the
cooler scenario, but that compares to record-shattering temperatures
in the mid 70s if the front stays just north. So our confidence
remains very high that Christmas will be mild, but our confidence in
record-breaking temperatures has decreased considerably relative to
prior forecasts.

While confidence in Thursday temperatures has decreased along and
north of I-70, confidence in the warmth sticking around past
Thursday has increased. Guidance again shows another shortwave
trough rounding, and flattening, the top of the ridge, tracking
through the southern Great Lakes on Friday. Most of our area remains
on the warm side of this track, so the extreme warmth continues. In
fact, it may be a touch warmer on Friday than Thursday depending on
the positioning of the front. And by Saturday we likely see one
final push north of the warm air before a strong cold front pushes
in from the northwest and ends our midwinter warmth. All in all this
sets up about 4 days of warm temperatures, but with daily
uncertainty around frontal position which affects whether we reach
record levels or not.

Guidance is in strong agreement that a deep trough will dig out of
the Pacific Northwest and into the central US by Sunday with a
strong cold front bringing a shift from very warm to much cooler
weather. There remains some uncertainty on the positioning of the
trough and how cold the incoming air will be, but confidence is high
that this will end the anomalous warmth. High temperatures on Sunday
range from the mid 40s to near 50 in the warmer scenarios to the low
to mid 30s in the colder scenarios. So even on the milder end, this
cool down brings us closer to normal for late December. On the
cooler end, we even head back below normal which will feel like
quite the shock compared to the preceding warmth.

Kimble

&&

.AVIATION...  (For the 00z TAFs through 00z Tuesday Evening)
Issued at 536 PM CST Mon Dec 22 2025

A cold front will push southeast into the CWA tomorrow morning.
To the immediate north of the front, fog is likely, but the
extent/density of it is still uncertain. To the south, MVFR clouds
are expected. These clouds are forecast to remain to the south of
the terminals, but a small shift in the forecast could change
this. Winds will diminish this evening, becoming light. Generally
southerly winds will veer nearly 360 degrees between now and 12z
Wednesday.

Jaja

&&

.CLIMATE...
Issued at 220 PM CST Mon Dec 22 2025

Well above normal temperatures are expected for much of Christmas
week. Record high temperatures are within reach on several days.
Daily record highs for each site are listed below.

 St Louis    Columbia    Quincy
12/2473(2021)74(2021)69(2021)
12/2571(1889)74(1889)66(2019)
12/26   70(1942)    69(1942)    63(1942)
12/27   72(1971)    71(1946)    70(1946)

The all time December record highs are listed below.

St Louis - 76 most recently on Dec 3, 2021
Columbia - 76 most recently on Dec 15, 2021
Quincy - 75 on Dec 15, 2021


&&

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&

$$

WFO LSX