St. Joseph, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

670
FXUS63 KEAX 061818
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
118 PM CDT Thu Aug 6 2026

.KEY MESSAGES...

- Residual shower/storm activity persists through this morning.
  Additional chances for showers/storms this afternoon/evening,
  generally south of I-70, with primary hazards being heavy rain
  and strong winds.

- Additional chances for precipitation through the end of the
  week.

- Hot and humid conditions building through the weekend into
  early next week, with heat indices near the triple digits.

&&

.DISCUSSION...
Issued at 331 AM CDT Thu Aug 6 2026

Overnight, a cluster of thunderstorms has persisted generally south
of US-36, following along a pronounced LLJ and synoptic-scale
diffluence in the mid-upper levels of the atmosphere. Amidst ~40 kts
of effective bulk shear and 1000-2000 J/kg of MUCAPE persisting
after sunset, these storms have remained robust enough for damaging
winds and hail to impact portions of the CWA. Through the remainder
of the overnight , the severe threat will begin to diminish with
decreasing CAPE and effective shear as the LLJ shifts off towards
the south and east. However, another caveat of tonight`s activity
has been very efficient rainfall rates out of thunderstorms, with
enhanced moisture convergence along a stationary boundary draped
across northwestern Missouri and PWATs around 2-2.5 inches. Although
activity has become more spaced out through the night, thinking for
the remainder of the overnight period is that, while the severe
threat will continue diminishing, the hydrological threat will
continue through tomorrow morning with any convection that fires
along the LLJ and broad shortwave trough in the low/mid-levels.

Through the late morning, the orientation of the LLJ will shift more
southwesterly/northeasterly as it progresses into central MO, with
residual precipitation following along its nose. High pressure
situated over the northern Plains building into northern MO may lead
to some patchy fog through the morning, but confidence is not high
enough for widespread dense fog development under residual cloud
cover from tonight`s activity. Dry air dredging in behind the
retreating shortwave will help dry out the forecast into tomorrow
for parts of the area, with temperatures residing in the 80s.
However, south of I-70, a continued severe threat exists with warm
advection and higher dewpoints enhancing instability during the day.
The greatest hazards with this severe threat would be heavy rainfall
and strong winds, with varied solutions on exact coverage/timing of
thunderstorms during the day. The overall synoptic pattern looks to
remain similar through the end of the week, with the forecast area
residing along the periphery of an upper-level ridge situated over
the southwestern CONUS and an upper-level trough over the Hudson
Bay. Under this setup, additional disturbances in the flow will lead
to continued PoPs through Friday evening. Going into the weekend,
the upper-level ridge over the southwestern CONUS looks to build
more over the forecast area, pushing the upper-level disturbances
and subsequent PoPs more towards the north and prevailing low-level
winds out of the south. With this adjustment, temperatures will
climb into the 90s by early next week, with coincident rising
dewpoints helping to bring apparent temperatures into the 90s and
even the triple digits.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 107 PM CDT Thu Aug 6 2026

Precipitation has moved east of the terminals, with dry
conditions likely to persist through the period. MVFR CIGs
continue this early afternoon, but CIGs should return to VFR by
later this afternoon and remain VFR through the remainder of the
period. Winds should be generally light (less than 8 knots) and
variable through the period.


&&

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

&&

$$

DISCUSSION...SPG
AVIATION...BMW