St. Joseph, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

565
FXUS63 KEAX 251752
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1252 PM CDT Thu Jun 25 2026

.KEY MESSAGES...

- Showers and storms are expected to move in from the west this
  afternoon. Some storms could be strong to severe with the
  primary hazards being damaging winds and large hail.

- These showers and storms will also be capable of producing
  heavy rain. Flash flooding will be possible. A Flood Watch
  remains in effect through Friday morning.

- Hot and humid weather engulfs the region starting Sunday and
  lingers into early next week. Heat indicies increase to
  100-110. An Extreme Heat Warning may be needed.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 1250 PM CDT Thu Jun 25 2026

A stalled out boundary is draped across west to east across the
metro this afternoon. Satellite and radar trends have pointed
to some destabilization along this boundary with some more
aggravated cu development. Coverage remains spotty but the
environment can be categorized as a moderate instability with
MLCAPE around 1000 J/kg with some weak bulk shear around 30 kts.
Some stronger storms could develop in these conditions and may
produce some gusty winds and small hail. Chances for storms
increase later this afternoon and through the evening hours as a
shortwave advances in from the west with a surface low lock in
step with it. Presently, this shortwave is tied to an MCS out in
central KS. High res guidance has this complex sliding across
our southern counties this afternoon. However, there may be
additional development along the stalled boundary. The
shortwaves arrival will also bring with it some better synoptic
forcing and an increase to our bulk shear values. This
combination may lead to strong to severe storms developing with
the main threat being damaging winds and large hail. One
pitfall for this forecast is the large area of cirrus blow off
from the MCS out west. This could act to help stabilize the
environment and lead to more of a stratiform rain event with
some embedded lighting, as opposed to some of the severe
weather that has been mentioned.

This evening, fueled by a enhancing low level jet with speeds
up to 50 kts these storms are expected to persist through the
overnight hours as the low slowly tracks across MO. The current
forecasted path of the low would lead to the heaviest rainfall
axis being across our southern half of our counties where our
Flood Watch is still in effect. The latest HREF also supports
some local flooding remains possible with the LPMM highlighting
a few swaths in excess of 2".

&&

.LONG TERM /FRIDAY THROUGH THURSDAY/...
Issued at 1250 PM CDT Thu Jun 25 2026

Friday morning the low pressure is projected to be over northeast MO
leading to some lingering showers and storms. By mid day this system
will have shifted out of the region with cooler northwesterly winds
streaming across the area. The relief will be brief as upper level
riding nudges in from the west bringing some warmer temperatures.
But dewpoints should be lower leading to less muggy conditions then
the previous day.

Temperatures really ramp up as we head into the weekend. A deepening
trough entering the west coast leads to strong ridging over central
CONUS. A surface low developing out of the Northern Plains will
further enhance the southerly flow across the region leading to a
hot and muggy period. Heat indicies are expected to climb into the
triple digits by Sunday and linger into next week. The long nature
of the heat coupled with poor recovery at night may warrant a
Extreme Heat Warning.

Rain chances through the weekend are not overly favorable. The best
chance looks to be initially on Saturday afternoon as a warm
front lifts north. But poor agreement amongst guidance is
keeping chances low around 20-30%. The rest of the period has to
contend with strong warm air aloft keeping the atmosphere
capped.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1250 PM CDT Thu Jun 25 2026

A stalled out boundary over the KC metro is leading to a few pop up
showers to start the forecast period. Confidence is low for these
showers to produce lightning initially. But as we head into the
afternoon hours, probabilities increase with a shortwave and
low pressure advancing out of KS. This pairing will cross the
the metro leading to heavy rain and some strong to severe storms
possible. The latest high res guidance would suggest that
activity will start to taper off tomorrow morning with some
lingering showers until late morning. Ceilings are expected to
fall to MVFR with the initial onset of showers and storms and
continue to descend into IFR conditions by tomorrow morning.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...Flood Watch through Friday morning for MOZ028>032-037>040-
     043>046-053-054.
KS...Flood Watch through Friday morning for KSZ057-060-103>105.

&&

$$

SHORT TERM...Britt
LONG TERM...Britt
AVIATION...Britt