St. Joseph, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

766
FXUS63 KEAX 301132
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
632 AM CDT Thu Jul 30 2026

.KEY MESSAGES...

- Isolated to scattered showers and storms expected early this
  morning. Isolated precipitation chances continue through the
  day along and west of the I-35/I-49 corridors.

- More widespread showers and thunderstorms expected overnight
  (Thu into Fri) as a thunderstorm complex moves through the
  area. Heavy downpours and gusty winds are expected; however,
  storms are expected to move through the area fairly quickly
  exiting just after 8am.

- Additional showers and storms are possible Friday evening
  south of I-70. There is a potential that a few of these storms
  may be strong to severe; however, this is highly conditional
  on activity Friday morning.

- Substantially cooler conditions expected Saturday with highs
  in the low to mid 80s forecasted. Temperatures warm back into
  the 90s next week.

&&

.DISCUSSION...
Issued at 252 AM CDT Thu Jul 30 2026

Similar programming to last night for the weather pattern. A surface
high over northern IL has advanced a little further south and a bit
further west. Likewise, the H500 high over NM continues to send
ridge running shortwaves around the system. Once again, these
shortwaves trigger showers and thunderstorms across the Sand Hills
and the foothills of the Rockies. Additional convection is
anticipated across central and eastern KS through the overnight.
Like Wednesday morning, the surface high is expected to limit the
ability for showers and storms to migrate eastward. Expectation are
for storms to approach far eastern KS before weakening as they
approach the MO/KS state line. A few sprinkles and showers are
expected to make it into the I-29/I-49 corridors through the early
morning.

Lee cyclogenesis across western KS catalyzed by a notable upper
level shortwave will be the primary influence of our weather through
the day. Broad scale southerly flow once again advects warm air and
moisture into the region. CAMs show a combination of turbulent
surface convergence (largely due to some variability in low level
winds), isentropic ascent, and some mesoscale upper level lift from
smaller H500 perturbations. This keeps isolated chances for showers
and storms around through much of the day for places west of the I-
35/I-49 corridors. Most likely we will see something similar to
yesterday where isolated to scattered light showers move through the
area through the daytime hours.

Through Thursday afternoon, another lee cyclone develops across NW
Nebraska in the more progressive flow across the Upper Midwest. A
cold front extends from this system and the frontogenetic energy
helps enhance the smaller wave anticipated over eastern KS. Low
level southerly flow accelerates advecting more warm air and
moisture into the area ahead of the systems arrival. The complex of
showers and thunderstorms is expected to work its way into the
region after midnight. Guidance continues to maintain fairly
progressive movement of the thunderstorm complex with it exiting the
region just past 8am. Elevated dew points and PWATs around 2 inches
continue to favor an environment for torrential downpours; however,
the progressive movement of the storms does limit several
hydrological concerns. The trade off is the faster storm motions
bring in the potential for damaging winds. The convective
environment shows just enough shear and instability to be a bit
concerned for an isolated strong to severe storm with the most
likely hazard being damaging wind gusts.

Unfortunately, the passing front does not do too much to curtail
heat for the day Friday. Cyclogenesis persists across the I-80
corridor and turns winds westerly advecting hot air from the
foothills of the Rockies into the area. Temperatures along and south
of I-70 rise into the 90s. Those north of the MO River will see a
more NW flow of the winds which lowers highs into the mid to upper
80s across far northern MO. Additional showers and storms are
possible Friday afternoon as a synoptic scale front follows behind
the overnight system. Warm air advection from the west looks to
destabilize the region and lead to the development of additional
showers and thunderstorms ahead of the front. Depending on how much
the atmosphere is able to recharge, some robust convection may
develop. The likely area for these potentially stronger storms is
across SW and Central MO. It is plausible for some strong to severe
storms with heavy rain, damaging winds, and hail being the likely
hazards. Behind the synoptic front, temperatures fall substantially
with highs Saturday expected to be in the low to mid 80s.

The extended forecast continues to show eventual breakdown of the
large H500 ridge over the SW CONUS. This opens up the pattern to
potentially become a little more active next week as the more active
zonal flow which has resided across the northern CONUS for the past
several days is able to progress further into the interior CONUS.
Likewise, southerly flow reopens and sends temperatures back upward
into the 90s next week.

&&

.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 624 AM CDT Thu Jul 30 2026

Areas of SHRA to the west are expected to gradually envelope the
area over the next couple of hours. So far, impacts have been
fairly limited, but potential +RA may dip conditions temporally.
SHRA/TSRA chances linger through much of the morning with
additional chances later in the period. The greatest chances of
storms is during the overnight particularly at the tail end of
the period. Winds remain generally southeast between 8-12 knots.

&&

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

&&

$$

DISCUSSION...Pesel
AVIATION...Pesel