St. Joseph, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

914
FXUS63 KEAX 250701
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
201 AM CDT Thu Jun 25 2026

.KEY MESSAGES...

- Potent disturbance will bring rounds of heavy rains and storms
  this afternoon and tonight

- A Flood Watch is in effect for much of the area along and
  south of I-70 from this afternoon into early Friday morning

- Increasing heat and humidity with little to no rain chances
  (20% or less) this weekend into next week. Heat indices rise
  to 100 to 110 Sunday through Wednesday.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 200 AM CDT Thu Jun 25 2026

National radar mosaic shows an east/west oriented boundary helping
maintain showers and storms from eastern CO to northwest OH.
Activity along this boundary has been enhanced over north central
and northwest KS with more widely scattered storms farther east.
GOES water vapor imagery shows a fairly potent upper wave coming
over the Rockies this hour.

The crux of today`s forecast lies on how far south that surface
boundary gets and then what happens with the wave upstream. Hi-res
model guidance have not handled these features that well, so it
leads to a little lower confidence in the timing/location forecast.
That said, we do have plenty of moisture available to work with, per
GOES sounder data showing a bubble of 1.5+ inch precipitable water
over the northern half of MO and a pool of available moisture over
OK/KS.

The leading edge of the shortwave will get into eastern KS later
this afternoon. Will current activity over northern KS merge into an
MCS and blast through during the daytime hours or will the current
activity weaken and allow for new development this afternoon that
pushes into our region at the current forecast peak time (for severe
potential) of 4 PM-9 PM? Either way, rain chances are high for
today, and the current Flood Watch area looks good...with current
areal average QPF around 2". Interesting that HREF LPMM shows a
bullseye of up to 7" just south of our southern border. That`s a
reasonable high-end amount in the high pwat environment we`re in,
but the exact location may waiver north/south, again based on how
that surface convergence boundary meanders today.

Expect frequent updates to the forecast as we track all of these
features and try to probabilistically feature the areas most at
risk. The southern edge of the storm activity will have better
access to instability to work with, and at this time that looks like
it would be south of the KC Metro. However, should the upstream
system weaken some, we could get some pockets of instability farther
north. If that lines up with the surface convergence boundary, we
could get some locally damaging wind gusts.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Issued at 200 AM CDT Thu Jun 25 2026

General troughiness remains along with the juicy airmass even into
Saturday. Will continue to carry pops...and may have to watch for
pockets of locally heavy rainfall. Given the lack of an organized
system moving through, not planning on extending the Flood Watch
beyond the current Friday morning expiration.

The next big story, which comes with high confidence, is a hot
pattern starting Saturday and continuing well into the work week.
Ridging aloft will pair with strong southerly surface winds Saturday
through Monday to bring that warm air quickly over us. Heat Indices
likely will peak well above 100 degrees each afternoon. Current
messaging focuses on the sudden change from our recent cool pattern
and how this will impact outdoor activities.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1241 AM CDT Thu Jun 25 2026

Complicated forecast next 24 hours with timing of shower/storm
chances as well as cigs/vsby. There is a boundary roughly from
KMCI eastward that has sparked some cells early this morning and
we have some cells trying to survive from the NW. Put in a
couple hours of rain chances at KSTJ to account for the latter
activity, but will have to see if anything lights up at the
KMCI/KMKC sites. Confidence not high at this time.

Then we have the afternoon wave coming through. Models have been
all over the place for how far north/south activity fires off,
and the two areas mentioned above will have some impact on how
the afternoon/evening fires off. Have gone with shower chances
with prob30 groups for tsra in general...but have a little more
confidence with KIXD being farther south that they could see
tsra as the dominant type.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...Flood Watch from 1 PM CDT this afternoon through Friday
     morning for MOZ028-029-037>040-043>046-053-054.
KS...Flood Watch from 1 PM CDT this afternoon through Friday
     morning for KSZ057-060-103>105.

&&

$$

SHORT TERM...Sharp
LONG TERM...Sharp
AVIATION...Sharp