St. Joseph, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

352
FXUS63 KEAX 230834
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
234 AM CST Tue Dec 23 2025

.KEY MESSAGES...

- Very warm temperatures are expected across the region through
  Saturday, with record highs in jeopardy later this week. Dry
  conditions will persist through the upcoming weekend.

- Patchy fog is expected to develop this morning (mainly for
  areas near/south of I-70) and again tonight (best chances
  south and west of KC).

- A strong cold front will move through the area this weekend,
  bringing sharply colder temperatures for Sunday and Monday.
  There is a 40 to 70 percent chance for wind gusts exceeding 30
  mph and a 10 to 30 percent chance for wind gusts exceeding 45
  mph on Sunday.

&&

.DISCUSSION...
Issued at 157 AM CST Tue Dec 23 2025

Despite the rather stagnant pattern across the central U.S. the
past few days, this has been a rather fascinating period in
terms of forecast predictability. With broad ridging in much of
the CONUS expected to persist through the week, there are still
some rather challenging aspects to the forecast, owing in large
part to small-scale perturbations ejecting from a deep trough
near/off the Pacific Coast and very poor run-to-run model
continuity exhibited with these perturbations for the past 48-72
hours. The main forecast challenges this morning appear to be
bouts of fog and/or low stratus through Thursday, decreasing
confidence in high temperatures through the weekend, and a
strong system affecting the area during the weekend.

The ridge will be building in the central U.S. in earnest today,
and I expect temperatures to warm nicely in this pattern,
despite potential for some persistent fog this morning in
portions of the area. Another issue preventing stronger warming
will be a lack of stronger surface winds today, which will not
only act to keep any fog that develops in place for longer this
morning, but it will reduce effective mixing and potential warm
advection. Any trend upward in warmth today will likely be in
large part due to insolation (which should be more abundant than
yesterday). Despite several limiting factors, I raised
temperatures a little bit above consensus today owing to the
pronounced amplification of upstream ridging and the increased
sunshine expected. Highs should be in the mid to upper 50s in
north-central/northeast Missouri to the upper 60s south of KC.

There is fog potential once again tonight as a weak perturbation
approaches the area from the west, and return flow begins to
creep into the region, supplying warm/moist advection. Winds
will still be fairly light, but given the increased lift just
above the surface, this may play out as more of a low-stratus
scenario than a fog scenario. Nevertheless, HREF probabilities
for visibilities less than a half mile approach 50% again to the
south and west of KC. Definitely cannot rule out fog, but low
clouds are a safe bet. Lows tonight are expected to be a few
degrees above average highs for this time of year.

It only gets warmer on Wednesday and Thursday, but model trends
have raised some concerns about just how high temperatures will
go for Christmas Eve and Christmas Day. With multiple
perturbations moving through the area in this period, low-level
lift via warm advection will provide widespread cloudiness for
large chunks of these two days. As discussed a couple of days
ago, these perturbations have also trended farther south in
their track, which would act to dampen the large-scale ridging
in the central U.S. Although the pattern obviously favors
anomalously warm temperatures, even with persistent cloud cover,
the probability for 70+ degree highs has sharply decreased over
the last 24 hours near/north of I-70 (and is basically near-zero
percent north of U.S. Highway 36). Current highs are in the mid
60s for the KC area this period, which would be well below the
record on Dec 24 and near the record on Dec 25. This will all be
dependent on cloud cover, and with the trend being more
pessimistic, confidence has lowered with record temperatures
being reached.

Another interesting trend is the continued warmth on Friday and
Saturday. After about four days of windshield wiper action in
model land, model consensus is trending toward warmer for this
period. This occurs because the Thursday perturbation tracks
east quickly on Friday and strengthens quickly, leading to a
period of transient amplified ridging in the central U.S. As a
result, highs on Friday and Saturday are in the 60s. And with
large-scale descent on Friday, cloud cover may be considerably
less prevalent than on Thursday. So Friday could end up being
the warmest day of the period now, with record highs on this day
in jeopardy!

The final trend of note in the forecast period is the very
strong system developing in the northern-stream flow in southern
Canada, with a trough digging rapidly southeastward Saturday
afternoon/evening into the northern Plains. The attendant cold
front will likely blast through the area late in the day into
Saturday night, with a very strong pressure gradient developing
as an intense polar high shifts southeastward upstream of the
system. This suggests a windy period is in store for the area
Saturday night and Sunday, and I suspect our forecast winds will
increase markedly as the event draws nearer (and confidence
increases). This will be a very rude awakening temperature-wise,
with a 30+ degree drop in highs possible from Saturday to
Sunday. With such a strong surface high developing, it will take
a couple of days for the region to recover, with much cooler
conditions lasting through at least early next week. Models are
beginning to hint at a very similar type of system affecting the
area around New Year`s Day as well.

&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 948 PM CST Mon Dec 22 2025

For the 06z TAF issuance, have included a period of LLWS of 35
kts through the lowest 2000ft through 09-12z window based on
observations. Have refined the extend and intensity of the
expected fog/low stratus development late tonight into Tuesday
morning. This included removing fog at STJ, keeping MVFR at MCI,
adding a TEMPO IFR group centered at 12z at MKC, and lowering
cigs/vsbys to IFR and/or LIFR at IXD centered around 14z.

Steady S-SW around 5-10 kts will become light/variable during
the predawn hours. A dry cold front will pass from N to S during
the late morning and afternoon, bringing a shift to N to NE
winds at 5-10 kts.

&&

.CLIMATE...
Issued at 157 AM CST Tue Dec 23 2025

Record High Temperatures:

December 24:
KMCI: 72/2021
KSTJ: 69/2021

December 25:
KMCI: 67/1922
KSTJ: 65/2019

December 26:
KMCI: 66/2008
KSTJ: 65/2008

Record High Minimum Temperatures:

December 25:
KMCI: 53/1936
KSTJ: 51/1936

&&

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

&&

$$

DISCUSSION...CMS
AVIATION...WFO EAX
CLIMATE...CMS