St. Joseph, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

999
FXUS63 KEAX 260933
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
433 AM CDT Wed Aug 26 2026

.KEY MESSAGES...

- Patchy to dense fog this morning.

- Near seasonal temperatures (afternoon highs in the mid to
  upper 80s) expected for today through Friday.

- Hot and more humid conditions likely this weekend into early
  next week.

&&

.DISCUSSION...
Issued at 332 AM CDT Wed Aug 26 2026

Current H5 analysis depicts a 598 dam H5 high centered over New
Mexico with attending mid/upper ridging extending northward all
the way into Alberta, with an upper trough extending from
Ontario into the Upper Midwest. This continues to yield
northwesterly flow aloft over the region. At the surface, a very
relaxed pressure gradient has resulted in calm winds, and with
solid moisture return between yesterday afternoon and this
morning pulling dew points back to the upper 60s to lower 70s
and saturating the boundary layer, patchy to dense fog has
developed across the region. The most dense fog, where
visibility is on the order of quarter to half mile, is across
far NW Missouri, which has prompted the issuance of a dense fog
advisory. Fog should mix out by around 9 am this morning. By
later today, a surface low associated with the upper trough
across the Upper Midwest will move eastward across Ontario, with
a trailing cold front moving northwest to southeast across the
CWA. This will yield a bit of a gradient for high temperatures
today, with high temperatures in the mid 80s across northern MO
where the front will move through later this morning and highs
in the upper 80s to lower 90s further south where the front will
arrive a bit later this afternoon. Drier air will filter in
behind the front, with dew points projected to fall to the mid
60s by this evening. For tomorrow, seasonal temperatures are
expected, but with dew points in the upper 50s it should be a
relatively pleasant day and evening. Temperatures may increase
a degree or two on Friday, but humidity should remain
relatively comfortable.

By this weekend, the upper ridge axis is progged to drift
further east as an upper trough comes ashore across the Pacific
Northwest (and will also flatten out the ridge). This should
lead to increased mid level heights and warmer 850 temps,
translating to surface high temperatures into the lower to mid
90s for Saturday. By Sunday and Monday, the center of the H5
high shifts eastward over the region. The upper trough will make
its way across the Intermountain West and into the Northern
Plains, with southerly low level flow increasing across our CWA
in response and ushering in some moisture return. Highs on
Sunday are forecast to reach the mid 90s for most locations, and
highs in the lower to mid 90s on Monday. However, recent trends
in the guidance has lowered temps and dew points a bit, and the
current grids reflect max heat indices on Sunday and Monday in
the mid to upper 90s (rather than 100 to slightly above 100 this
time yesterday). Shower and thunderstorm chances return to the
forecast Sunday night into Monday morning (20 to 40%) and again
Monday night into Tuesday morning (20 to 50%).

&&

.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 1058 PM CDT Tue Aug 25 2026

Skies will continue to clear overnight. Some areas may see fog,
and expected to fog in along the Missouri River Valley which
will impact the STJ terminal. A few clouds may start to clip
eastern KS and western MO by the middle of Wednesday morning.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...Dense Fog Advisory until 9 AM CDT this morning for MOZ001-002-
     011-012-020.
KS...Dense Fog Advisory until 9 AM CDT this morning for KSZ102.

&&

$$

DISCUSSION...BMW
AVIATION...BMW