St. Joseph, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

078
FXUS63 KEAX 041731
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1231 PM CDT Thu Jun 4 2026

.KEY MESSAGES...

* Shower and storm chances today through Friday. Strong to
  severe storms are possible tonight and again late Friday.
  Heavy rain will also be possible. There is a Flash Flood Watch
  out for northwestern Missouri and far northeastern Kansas

* Warmer and humid conditions return by the end of the week,
  continuing through the 7-day forecast.

* Heat index values into the 90s, including mid-upper 90s,
  possible at times next week.

&&

.SHORT TERM /THROUGH FRIDAY NIGHT/...
Issued at 340 AM CDT Thu Jun 4 2026

Rain and thunderstorms chances are in store for the short term
forecast across western KS and northern MO. The high pressure and
upper level ridging that has been dominating the pattern for the
last couple of days will finally shift off to the east. As the
ridging aloft moves off, a shortwave trough will move from the Rocky
Mountains into the Central Plains. Trapped between this incoming
shortwave and an exiting high, south to southwest winds will bring
in some good WAA. This will drive temperatures and dewpoints up
across the region. While temperatures are only expected to change by
a few degrees, dewpoints are expected to climb into the 60s. Today
will have some upper level support with the shortwave and good
moisture, but we will overall be lacking any type of forcing/trigger
at the sfc. So while its highly likely that we will destabilize
enough, the question becomes when does rain/storms fire and how
isolated is it. Storms should be largely unorganized with
thunder/lightning being the primary concern. Can`t rule out brief
gusty winds or small hail if a storms gets tall enough, but shear
isn`t super great. This with the lack of forcing will leave the CWA
with isolated pop up storms in the afternoon and evening that
are unorganized.

Heading into tonight, mainly for areas north of I-70, storms are
expected to continue as the LLJ kicks in and WAA persists. This
will provide a slight boost to the shear. So if there is
anything more organized it will be tonight into Friday. Heavy
Rain, wind, small hail and lightning look to be the primary
concerns here. Any convection that lasts into the early morning
hours Friday should weaken as the LLJ diminishes. PWATs will be
high across northwestern MO and far eastern KS in and around the
90th percentile. Despite the dry soils, there looks to be an
axis of 1-3 inches of rain that will fall across northeastern KS
into central IA. This would run through the bluff areas across
northern MO and could be a concern for urban areas and flashy
rivers, especially if totals lean towards the high end (3
inches). Due to the concerns for heavy rain a Flash Flood Watch
has been issued for the northwestern portions of the CWA this
afternoon through Friday morning.

Looking into Friday, guidance is really hinting at a lull in
rain/storm activity through the late morning into the early
afternoon which would give EAX a chance to destabilize again for
the afternoon. If skies clear this could allow for good airmass
recovery. Good lapse rates, strong instability and good shear.
The better chances for strong to severe storms will mainly be
across the northern third of the forecast area, well north of
I-70 (US-36 corridor and north). This line up well with the SPC
outlook for those of us who love a visual.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
Issued at 340 AM CDT Thu Jun 4 2026

Kicking off the long term, there is upper level ridging that will
amplify across the central CONUS Saturday into Sunday and a
deepening trough across the Pacific Northwest. This amplified
trough will move east with time into the eastern CONUS for early
next week. Meanwhile, a cut off low will eject out of the TX
and OK for the weekend. POPs will build across the region from
the southwest to the northeast late Saturday into Sunday as this
cut off low builds in. Ahead of this incoming low, mid level
and low level WAA will be well underway. Guidance has taken
quiet the jump with the latest runs tapping right into the
gulf. Sfc dewpoints climb into the low to mid 70s at times for
the NBM, which could be a bit overdone at times throughout the
extended forecast. Regardless, this signals a good potential for
some afternoon destabilization with highs in the 80s. The one
variable holding us back here will be our wind shear. Its
overall very weak and is often falling short of 25-30 kt
threshold needed for more organized convection. Model
variability still exists as well which leads to overall lower
confidence on severe potential. Now if shear increases the game
is on for some stronger storms, but until then thunder and
widespread rain looks to be the name of the game. The one thing
to keep an eye on for this system is how much rain we get. Still
a lot of time here and some uncertainty in rain amounts and
just exactly where that axis of higher rainfall will be, but
something to watch.

Precipitation chances will linger into early next week with POPs around
40-70% Monday morning. Precip chances will decrease from west
to east with time with more drier air working in. As the cut off
low pulls away to the northeast, the larger scale ridging will
take over as the dominant pattern Tuesday. With largely
southerly to southwesterly flow, WAA will remain across the
region. That combined with the ridging will lead to some warm
and sticky conditions for EAX. Again, the average among
guidance did jump a bit in regards to temps and dewpoints from
roughly Tuesday through Thursday. Highs generally are in the low
90s, but dewpoints range from the lower to upper 70s. The
combination of high temps and dewpoints due lead to some heat
index concerns, however, there is lower confidence in dewpoints
reaching the upper 70s. Its going to take some serious WAA out
of the gulf to actualize those higher dewpoints. Long and short
is if you are susceptible to high heat keep an eye on Tuesday
through Thursday, but dont be shocked if there is a trend
downward away from those higher dewpoints.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1230 PM CDT Thu Jun 4 2026

Currently observing a cu field developing on satellite at most
terminals, with the potential for afternoon showers/storms to
develop at terminals through the afternoon. Greater confidence
is in the development of showers/storms overnight, developing
over northwest MO/northeast KS with the potential to develop
downward overnight to downtown terminals. Expecting
showers/storms to exit the vicinity of terminals around 9-12z
tomorrow morning as cloud ceilings lower to MVFR, with gustier
winds persisting at terminals through the late morning/early
afternoon. Winds expected to remain generally southerly around
10-15 kts through the forecast period.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...Flood Watch through Friday morning for MOZ001>005-011>013-020.
KS...Flood Watch through Friday morning for KSZ025-102.

&&

$$

SHORT TERM...Patterson
LONG TERM...Patterson
AVIATION...SPG