St. Joseph, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

000
FXUS63 KEAX 141113
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
613 AM CDT Mon Sep 14 2026

.KEY MESSAGES...

- Multiple rounds of storms will bring a flooding risk,
  especially north of the Missouri River, through the middle to
  later part of the work week.

- Round 1 - Monday Morning: The severe weather threat from
  storms this morning is low, but there may be some hail to 1"
  in the strongest cells across northwestern and northern
  Missouri. Locally heavy rainfall is also possible.

- Round 2 - Monday Afternoon - Evening: There is a Slight Risk
  in far northwestern Missouri. If storms develop/ move into far
  northwestern Missouri, large hail, damaging winds, and tornadoes
  are possible.


- Round 3 - Tuesday Afternoon - Overnight: There is a Marginal
  Risk for severe storms for Tuesday afternoon into the evening
  hours. Strong to damaging wind gusts and hail are the main
  hazards. Storms become more widespread overnight with heavy
  rainfall likely across northern Missouri.

&&

.DISCUSSION...
Issued at 150 AM CDT Mon Sep 14 2026

Very active weather is expected over the first half of the work week
with multiple rounds of storms anticipated. For this morning, as of
writing this paragraph at 06Z, convective initiation is underway in
southeastern Nebraska and northeastern Kansas. This is developing in
an area of strong isentropic ascent noted from the 310K to 315K
surfaces. The threat of severe weather is low with this activity due
to only modest and elevated instability. But there may be cells that
occasionally push to near severe thresholds with hail being the main
hazard. Additionally, locally heavy rain, which will act to prime
the area for subsequent events, is likely with this activity as
ample moisture is transported into the area.

This initial activity will lift northeast through the morning hours,
leading into the next round of storms for the afternoon and evening
hours. It`s uncertain if storms will be able to develop/ overcome
the convective inhibition from the morning activity, but if they
do they will primarily affect Nebraska and Iowa. However, the
risk may bleed into northwestern Missouri with time and with
MLCAPE in the 1500-2000 J/kg range with potentially 30-35kts of
deep-layer shear, large hail, damaging winds, and tornadoes look
possible. This activity should slide south through the
overnight hours as its cold pool builds south, but will be
losing its strength as it does. But, that boundary may become
the focus for additional storms Tuesday afternoon.

An unseasonably moist airmass will build into the area south of this
boundary, with dewpoints in the lower 70s expected. Strong daytime
heating of this moist airmass will lead to potentially substantial
CAPE, possibly in excess of 2000 J/kg. With stronger mid to upper-
level flow still north of the area, deep-layer shear looks weaker.
Forecast soundings, particularly from the NAM, suggest deep mixing/
steep lapse rates will occur in the lowest 5000 ft of the
atmosphere. If storms are able to develop in this environment
damaging downbursts winds are the most likely hazard. Further north,
into the overnight hours, convection should become more widespread,
though with a more limited severe weather threat. But its this
activity that will pose the greatest risk for flooding rainfall,
with widespread 1-3" rainfall amounts across northern Missouri
possible from just this round of storms. Locally heavier
amounts are likely depending on where storms do develop and
eventually train given flow that is essentially parallel to the
boundary.

Additionally, with the hot and humid conditions anticipated, a
heat advisory may be needed for areas south of I-70 Tuesday
afternoon.

And in the 50 minutes it took to write the remainder of this,
storms have blossomed in southeastern Nebraska and northeastern
Kansas, and are moving in northwestern Missouri. So I`ll be
cutting this discussion a little short.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 605 AM CDT Mon Sep 14 2026

VFR conditions to prevail through the end of the period. Storms
ongoing across northern Missouri this morning expected weaken
and dissipate after sunrise. Maintained a brief PROB30 at KSTJ
for -TSRA to account for any storm developing behind the main
cluster. A warm front is forecast to move through E KS and W MO
over the course of the day...easterly winds this morning will
give way to southeasterly then gusty southerly winds by 18Z
today. Storms may be able to develop late this afternoon across
far NW MO...as the evening and overnight progresses, storm
chances will expand further south so have gone ahead and
included a PROB30 for -TSRA at KSTJ from 08Z to 11Z tomorrow.

&&

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

&&

$$

DISCUSSION...CDB
AVIATION...Macko