St. Joseph, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

989
FXUS63 KEAX 310401
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1101 PM CDT Sun Aug 30 2026

.KEY MESSAGES...

- Well above normal temperatures expected throughout most, if not
all, of the current forecast.

  - Heat Advisory for much of the area through at least Wednesday
  - Highs in the mid to upper 90s, possibly touching 100
  - Heat index values in the 100 to 105 range
  - Overnight lows warm in the mid to upper 70s

- Limited precipitation opportunities, mainly skirting far NW
  and N Missouri at times during the week, including tonight /
  Monday morning and Wednesday night / Thursday morning.

&&

.DISCUSSION...
Issued at 234 PM CDT Sun Aug 30 2026

Little change in the going 7-day forecast for much of the area. The
general bullet points remain as noted in the Key Messages ... well
above normal temperatures have settled in and will continue
throughout the week for most of the area, along with very limited
opportunities for relief / deviations from the overall forecast.

Current observations, in-situ and satellite, all depict overall
quiet conditions have settled in across the area. This after a few
showers and thunderstorms tracked across northern Missouri this
morning, admittedly further south than initially forecast. That
ultimately kept portions of northern Missouri a bit cooler this
morning, but temperatures rapidly rebounded with clear skies and
breezy southerly winds. By early to mid-afternoon, temperatures had
jumped well into the 90s for many, ranging from upper 90s / near 100
in southern areas of the CW to the low to mid 90s across northern
areas. This ultimately, and unfortunately, sets the table for what
one can largely expect throughout the work week.

The large scale pattern remains locked in across deterministic and
ensemble guidance. This includes a current mid-level / 500mb ridge
across the Southern Plains, gradually building into the Lower
Missouri and Mid-Mississippi River Valley areas. This feature will
slowly drift E/ENE through much of the work week. For much of the
forecast area this means hot and dry. Far northern areas (NW
Missouri and the Iowa-Missouri border areas) tend to find themselves
on the far southern edge or periphery of the ring of fire, and could
see brief periods of relief from shower/storm or cloud cover should
these features track far enough south. Best opportunities there
appear to be overnight tonight and again Wednesday night/overnight.
Otherwise, highs into the mid-upper 90s can be expected. Best
chances for any 100s will be along/near the Missouri River. This is
all bolstered by NBM probabilities of 95+ degree highs of 90 percent
or greater along and south of Highway 36 through Wednesday. A little
bit of good news, or at least not piling on, is that dew points are
not expected to be oppressive. This keeps Heat Index values mostly
below 105 during this time frame. A little bit of a wild card here
too will be just how deep we are able to mix during the day. Suspect
dew points may be a bit too moist in current forecast, as tendency
is for models to under mix in this type of setup. This would push
dew points a bit lower and further keep Heat Index values in check.
Additionally, overnight lows may provide limited or no relief with
overnight lows in the mid to upper 70s expected. Again, bolstered by
NBM probabilities of lows >75 degrees often in the 80 to 90 percent
or greater range. All of this works to yield the issued Heat
Advisory for most of the CWA, let alone wider region. For now, the
Heat Advisory goes through Wednesday, but may (likely) need to be
extended depending on how everything evolves.

Looking toward the end of the forecast and beyond, various guidance
retrogrades and amplifies this feature late week and through next
weekend as an Omega Block pattern looks to set up. The item to watch
here is just how far west the ridge axis retrogrades. At this time,
guidance tends to favor centering it over the Central Plains
(Nebraska/Kansas), which may provide an opportunity periods of brief
relief from ridge riding/rounding complexes. Northeast portions of
the forecast area would be most prone for that relief
opportunity.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1053 PM CDT Sun Aug 30 2026

VFR conditions are expected for the duration of the period.
Winds persist out of the south veering a little southwest after
sunrise. Intermittent gusts continue through the overnight
becoming more frequent after mid morning. Some diurnal CU is
expected but cloud bases are anticipated to be ~10,000ft or
higher.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...Heat Advisory from noon Monday to 7 PM CDT Wednesday for
     MOZ003>008-012>017-020>025-028>033-037>040-043>046-053-
     054.
KS...Heat Advisory from noon Monday to 7 PM CDT Wednesday for
     KSZ025-057-060-102>105.

&&

$$

DISCUSSION...Curtis
AVIATION...Pesel