St. Joseph, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

621
FXUS63 KEAX 120443
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1143 PM CDT Tue Aug 11 2026

...06z Aviation Update...

.KEY MESSAGES...

* Heat advisory/excessive heat warning in effect through
  Thursday/Friday along and south of highway 36.

* Low chances continue for overnight/morning showers and
  thunderstorms across the region, with best chances across
  northern Missouri.

* There is the potential for a few isolated strong storms tomorrow
  night and again on Thursday night with damaging winds and
  large hail the main threats.

&&

.DISCUSSION...
Issued at 145 PM CDT Tue Aug 11 2026

The main forecast concern today through Friday/Saturday will
continue to be the heat. As such, an Extreme Heat Warning has been
extended to include areas along and south of the Missouri River
where daytime heat index values will remain between 105-110 each day
and 75-80 each night. A Heat Advisory remains in effect through
Thursday evening north of the Excessive Heat Warning along the
Highway 36 corridor. This prolonged heat event will come courtesy of
a upper ridge that resides over much of the southern CONUS into the
central Rockies. This upper level ridge will slowly slide east
through the week with the ridge axis moving over the local area
Thursday. This will keep highs in the 90s to around 100 through
Thursday. The local area will be on the northern periphery of this
ridge, with weak shortwaves rounding the ridge moving into the area
providing occasional slight chance to chance PoPs (20-40%) across
northern Missouri though Thursday night.

Friday into Friday night, a relatively stronger shortwave will move
across the northern/central Plains into the Upper Midwest. This will
act to flatten the ridge and force a weak surface boundary into the
northern CWA. This is expected to bring slightly cooler temperatures
to northern Missouri with highs in the upper 80s to lower 90s.
However, south of this surface boundary temperatures will continue
to remain hot with highs remaining in the mid 90s to near 100. This
boundary may also be the focus for slight chance to chance (20-40%)
convection Friday into Friday night across the northern CWA.
Continued shortwaves are expected to help slowly force this boundary
southward through the area through the weekend continuing to keep
slight chance to chance PoPs around for the weekend. By Sunday,
temperature are expected to range from the mid 80s north to the mid
90s south. Monday, with the upper level ridge remaining flattened
across the region a shortwave is expected to move through the area
bringing another chance for storms which is forecast to aid in cooler
temperatures into the lower 80s to lower 90s.

&&

.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 1139 PM CDT Tue Aug 11 2026

VFR conditions remain expected to prevail across the sites
through the period. Winds also to largely remain out of the S to
SE around 10 kts and occasional gusts into the teens kts. Latter
portions of the period winds should begin to ease and see a
more easterly shift, most pronounced at KSTJ. Additionally, of
the sites, KSTJ is also the site most likely to `possibly` see
any precipitation activity. This would be from upstream
convection/MCS activity out of the portions of South Dakota and
Nebraska as they stream E/SE toward the area. Current hi-res
guidance suggests ~12z for an arrival in/around NE Missouri, but
also activity primarily in/across Nebraska and Iowa. At least
in regards to TAF sites.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...Extreme Heat Warning until 8 PM CDT Friday for MOZ028>033-
     037>040-043>046-053-054.
     Heat Advisory until 8 PM CDT Thursday for MOZ011>017-020>025.
KS...Extreme Heat Warning until 8 PM CDT Friday for KSZ025-057-060-
     103>105.
     Heat Advisory until 8 PM CDT Thursday for KSZ102.

&&

$$

DISCUSSION...73
SHORT TERM...
LONG TERM...
AVIATION...Curtis