St. Joseph, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

022
FXUS63 KEAX 130834
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
334 AM CDT Thu Aug 13 2026

.KEY MESSAGES...

- Dangerous heat continuing through the end of the week and into
  the weekend for some areas. An Extreme Heat Warning is in
  effect along and south of the Missouri River. A Heat Advisory
  is in effect south of US-136 along and west of US-65.

- Chances for showers and storms continue in the vicinity of a
  stationary front fluctuating between southern Iowa and
  northern Missouri. Lingering cloud cover could mitigate high
  temperatures over the next few days.

&&

.DISCUSSION...
Issued at 334 AM CDT Thu Aug 13 2026

MCS and associated MCV has pushed into eastern Nebraska as of 08Z.
850-300 mb mean winds suggests this complex will largely push east,
but as the complex moves east across Iowa, it is expected to take on
more of a northwest - southeast trajectory. Fairly substantial
outflow extend southward from the main complex. Atmosphere appears
to be weakly capped across northern Missouri, and have some chance
pops along the Iowa/Missouri border from 11-15Z as the main complex
slides to the east.  South of this complex, looking at another warm
and humid day with large upper level ridge centered across the Gulf
Coast and broad southeasterly flow extending northward into the
central US. With unseasonably mild air in place across the Central
US, we are once again looking at forecast highs in the 90s F and dew
points well in the 70s leading to heat indicies of 105-110 F across
the region. The only locations that may see a slight reprieve
from the heat will be across northern Missouri where the outflow
may temporarily keep conditions cooler.

Area of low pressure across western Kansas this morning is expected
to slowly shift eastward into central Kansas by this evening.  Ahead
of this system, low level jet is expected to strengthen feeding
into the remnant outflow leading to additional thunderstorm
development across northeast KS, lifting northeast into northern
Missouri. Precipitable water values are near the daily max
around 2 inches, and very deep warm cloud depths of 12-13K feet
will support very efficient warm rain processes. Flash flood
guidance across northern Missouri is generally in the
2-2.5"/3hr and 3-4"/6 hr time scales. If storms were to train
along the boundary, this could be quite problematic, though
there are few solutions to suggest this would be a possibility.
At this point, it appears the bulk of the precipitation is going
to be focused farther north where the cap is a bit weaker, but
will need to keep an eye on the flood potential across northern
Missouri in the coming days as warm front associated with the
slow moving low pressure system is expected to remain in
vicinity of the Iowa/ Missouri border.

Latest guidance suggests the low pressure system across KS is
expected to slowly lift northward into the Upper Midwest this
weekend, but eastern KS and Missouri remain in the warm sector
leading to heat continuing through at least the first half of the
weekend.  The cold front associated with this low is expected to
build southward across the region on Sunday, potentially leading to
showers and thunderstorms and potentially some relief from the heat.

Cooler conditions (potentially below normal temperatures) are
expected early next week, but heat and humidity return mid-to late
week in a return to a very similar pattern than we are currently
in.

&&

.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 1051 PM CDT Wed Aug 12 2026

Much the same continues across the TAF sites. This being VFR
conditions and any notable precipitation or non-VFR chances
tending to remain displaced northward. Winds overnight will
settle out of the SE to S up to around 10 kts. During daytime,
KC Metro sites may see sustained winds a bit above 10 kts with
gusts to around 20 kts at times. KSTJ will be a bit lighter, but
too should see sustained up to around 10 kts. Cloud cover to
remain well in VFR range with much of it residing around 15kft
or higher. But of note, should the Nebraska convection overnight
drift further south than CAM guidance suggests, some lower
ceilings would be possible at KSTJ. However, that probability
is low at this point so no mentions within the TAF.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...Extreme Heat Warning until 8 PM CDT Friday for MOZ028>033-037-
     038.
     Extreme Heat Warning until 9 PM CDT Saturday for MOZ039-040-
     043>046-053-054.
     Heat Advisory until 8 PM CDT this evening for MOZ011>015-
     020>023.
KS...Extreme Heat Warning until 8 PM CDT Friday for KSZ025-103>105.
     Extreme Heat Warning until 9 PM CDT Saturday for KSZ057-060.
     Heat Advisory until 8 PM CDT this evening for KSZ102.

&&

$$

DISCUSSION...BT

AVIATION...Curtis