St. Joseph, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

809
FXUS63 KEAX 021745
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1245 PM CDT Wed Sep 2 2026

.KEY MESSAGES...

- Well above normal temperatures expected to continue through the
  end of the week, likely through early next week.

    - Heat advisory expanded to the entire area through Friday
    - Will likely need to be extended into or through the weekend
    - Temperatures in the mid 90s to near 100
    - Heat index values as high as 105

&&

.DISCUSSION...
Issued at 258 AM CDT Wed Sep 2 2026

The main concern this forecast period will continue to be the well
above normal temperatures. Today, the upper level ridge axis that
was over the area over the course of the past 2-3 days will slide
eastward into the Tennessee and Ohio River Valley`s. This will
provide slight height falls which may drop temperatures a degree or
two with highs still rising into the mid to upper 90s. While
temperatures may "cool" a degree or two, moisture will begin to
increase slightly with dewpoints rising into the mid to upper 60s
allowing heat index values to rise into the 100-105 range. Thursday
the upper level pattern will remain unchanged keeping highs in the
mid to upper 90s however, dewpoints will continue to increase
slightly into the upper 60s to lower 70s. This will yield heat index
values in the 100-105 range with some locations south of the
Missouri River rising above 105. Friday, the upper level ridge axis
will retrograde back to the west with the ridge axis again centered
over the local area. This will keep highs in the mid to upper 90s
despite weaker WAA, in addition, heat index values will also remain
in the 100-105 range with some locations south of the Missouri River
again rising above 105.

Saturday, the upper level ridge continues to retrograde back to the
west into the Plains states. However, the local area remains under
its influence with highs still in the mid 90s to near 100 and heat
index values remaining in the 100-105 range for most for the area.
Model differences beyond Saturday as to how they treat the upper
level ridge leads to some uncertainty in the extended timeframe
(Sunday through Tuesday). The current NBM features periodic slight
chance PoPs (15-25%)in the forecast during this period. If the GFS
solution verifies the upper level ridge would retrograde further
back to the west across the western Plains. This would leave the
local area on the eastern periphery of the ridge with shortwaves
rounding the ridge bringing even greater precipitation chances to
the area. The EC reintensifies the ridge over the local area keeping
conditions dry. Both solutions do continue keeping temperatures
above normal with highs in the upper 80s to upper 90s.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1235 PM CDT Wed Sep 2 2026

VFR conditions are expected through the period with little to no
cloud cover. SSW winds will gust to 15-18kts this afternoon
before diminishing to 5-10kts around sunset.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...Heat Advisory until 8 PM CDT Friday for MOZ001>008-011>017-
     020>025-028>033-037>040-043>046-053-054.
     Air Quality Alert until 7 PM CDT this evening for MOZ028>030-
     037-043.
KS...Heat Advisory until 8 PM CDT Friday for KSZ025-057-060-102>105.
     Air Quality Alert until 7 PM CDT this evening for KSZ057-
     103>105.

&&

$$

DISCUSSION...73
SHORT TERM...
LONG TERM...
AVIATION...Shaw