St. Joseph, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

232
FXUS63 KEAX 070446
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1046 PM CST Tue Jan 6 2026

.KEY MESSAGES...

* Dense fog expected to develop again across portions of north-
  central and northeast Missouri again tonight.

* Increasing confidence in widespread precipitation (rain) chances
  arriving Thursday
  - 80% to near 100% across entire area
  - Heavy rain, >1.5", possible (40-60% chance)

* Additional precipitation chances Friday night into early
  Saturday, including some wintry precipitation possible
  - 30-50% chances
  - Greatest snow potential NW Missouri

* Temperatures cooler near seasonal norms through the weekend

&&

.DISCUSSION...
Issued at 312 PM CST Tue Jan 6 2026

Skies have mostly cleared across eastern Kansas and northwest
Missouri apart from a few lingering clouds in Schuyler and Adair
counties. Temperatures at this time are in the mid 50s to low
60s across the area. We`ll see fog and low clouds return again
tonight to our northeastern counties (north-central MO). Likely
will need another Dense Fog Advisory, but due to uncertainty in
extent, will leave this to the evening or midnight shift to
issue.

The upper-level pattern shows zonal flow with a negatively-
tilted trough off the coast of California which will bring a
strong system as it moves through later this week. As this
system moves into the Desert Southwest, we`ll see weak ridging
develop over the Central Plains with an increase in southerly
flow and warm-air advection on Wednesday. With this, expect
highs tomorrow to warm into the upper 50s to mid 60s across the
area. We`ll see increasing high clouds through the day as
moisture starts to pool out ahead of the developing surface low
over southwest KS/southeast CO. Overnight Wednesday night into
Thursday we`ll see rain move in from the southwest as the Low
tracks across Kansas toward our area. Models have continued to
trend this heavier precip band more northwest, now setting it up
squarely across our area, with the NBM showing a 60-70% chance
of over an inch of rain and some areas in the center of this
band seeing a 50-60% chance of 1.5 inches of rain on Thursday.
Good news is because of the lack of recent rainfall as well as
warm ground temperatures, this should just be a good, beneficial
rainfall with low potential for flooding.

As this first system moves out Thursday night, we`ll be watching
a second trough move through the Four Corners region. This
second system is trending weaker, now looking like more of an
open-wave system as it moves through on Friday. The GEFS
ensemble members continue to look cooler with a more southerly
track with the Low, bringing a band of light snow across
northwest Missouri, likely staying north of the KC Metro. The
ECMWF members tend to be a bit farther north with the band,
setting it up more across far southeast Nebraska. Both scenarios
likely bring snow to northwest Missouri areas, just differing in
amounts. Long-range ensembles show a 30-35% chance of an inch
of snow across areas just north of St Joseph and Trenton, with a
20-25% chance across the KC Metro northeast to Kirksville.
Probabilities really drop off between 1-2 inches, so expect
generally less than 2 inches of snow in this band, wherever it
sets up at this time. Timing looks to be delayed as well, with
rain changing to snow Friday evening and continuing into
Saturday morning.

Cooler air moves in on the back-side of this system for the
weekend with highs back down in the mid 30s to low 40s Saturday
and Sunday. Deterministic models both show a second weak
shortwave moving through Saturday afternoon, potentially
bringing flurries or a light dusting of snow. Ensembles may be
smoothing this out, leading to non-mentionable PoPs, so will dig
into this more as we get closer to Saturday. High pressure
slides across the region on Sunday leading to dry, cool
conditions with temperatures starting to rebound on Monday as
southwesterly flow returns.

&&

.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 1045 PM CST Tue Jan 6 2026

VFR conditions are very likely through the forecast. STJ may see
some river valley fog this morning but guidance shows only a
10-15% chance for fog development. Will keep fog out of the
forecast there for now and amend as needed. Otherwise, light
winds overnight will increase from the south-southwest tomorrow
with a few gusts to around 20kts possible. Winds diminish and
back to the south-southeast with loss of daytime heating.

&&

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

&&

$$

DISCUSSION...McCoy
AVIATION...CDB