St. Joseph, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

572
FXUS63 KEAX 300716
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
216 AM CDT Wed Sep 30 2026

.KEY MESSAGES...

- Several rounds of showers and storms will be likely across the
  area through Thursday night which may lead to heavy rainfall
  and flooding.

&&

.DISCUSSION...
Issued at 214 AM CDT Wed Sep 30 2026

The main change with this forecast package is to shift the axis of
heaviest forecast precipitation over the next 48 hours further
southward. Consequently, the flood watch has been extended one to
two counties south and eastward to cover most the area along and
north of the Highway 36 corridor. It is in this area that 2-5" of
precipitation is forecast. This flood watch will be in effect
through 1am Friday morning.

Early this morning, moisture continues to stream northward into the
area on a 40-45kt southwesterly LLJ. This is continuing shower and
isolated thunderstorm chances across the area overnight. The LLJ
never weakens during the course of the day today and continues to
nose into the area which will continue shower and thunderstorm
chances through the day today. Additional lift will be introduced
this afternoon as a couple lead upper level shortwaves will eject
out ahead of a closed upper level low which will slowly move through
the desert southwest today. This will provide for the better chance
for some thunderstorms this afternoon as well as the potential for a
couple rounds of heavy rainfall. PWATs this afternoon into this
evening will range between 2.00"2.25" which is near the 100th
percentile for late Sept/early October. Tonight, the closed low over
the desert southwest will move out into the western Plains forcing a
cold front towards he area. The persistent LLJ coupled with
additional lead upper level shortwaves will continue the potential
for addition heavy showers and storms. Tomorrow the closed upper
level low will move slowly across Kansas and force the cold front
slowly through the area during the day Thursday. PWATs will still
remain in the 1.75-2.00" range continue the chances for heavy rain.
Tomorrow night the upper level low finally opens up becoming a more
progressive wave as it moves through the region. This will bring one
last shot of precipitation to the area before he upper level system
shifts east by Friday morning. All told areas along and north of
Highway 36 are forecast to receive 2 to 4+ inches of precipitation
with 1 to 3 inches forecast further south. Highs today will be in
the mid 70s to mid 80s but will be cooler on Thursday as the cold
front moves through with highs ranging in the upper 60s to upper 70s.

Fortunately, conditions will dry out Friday and then look dry
through the rest of the forecast period. Friday and Saturday a
surface ridge of high pressure will dominate the area providing
early fall-like temperatures with highs in the mid 60s to mid 70s.
Sunday a upper level ridge of high pressure over the southwestern
CONUS will lowly shift eastward into the western High Plains. This
will provide gradual height rises across the area allowing highs to
rise a few degrees into the upper 60s to mid 70s. Monday a surface
ridge will build into the area from the northern Plains keeping
highs in the lower 60s to lower 70s. Tuesday the surface ridge of
high pressure shifts east of the area with modest WAA developing and
allowing highs to rise into the mid 60s to mid 70s.


&&

.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 1207 AM CDT Wed Sep 30 2026

Showers continue to move through the forecast area overnight, with
generally VFR conditions through the period. Some spots could fall
into MVFR or brief IFR with heavier showers, but because this would
be for a short duration and difficult to predict, opted to exclude
this from the TAFs. KSTJ is the exception, where MVFR/IFR is more
likely overnight due to the presence of a persistent heavier axis of
rainfall. At the metro terminals, precipitation will become more
scattered after sunrise. Could see a stray shower Wednesday
afternoon before showers and possibly a few thunderstorms increase
in coverage Wednesday evening.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...Flood Watch through late Thursday night for MOZ001>008-011>017-
     020.
KS...Flood Watch through late Thursday night for KSZ025-102.

&&

$$

DISCUSSION...73
AVIATION...Shaw