St. Joseph, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

901
FXUS63 KEAX 051952
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
252 PM CDT Fri Jun 5 2026

.KEY MESSAGES...

- Some isolated storms are possible this afternoon and evening,
  but more widespread storm coverage should remain north of the
  area towards Nebraska and Iowa.

- Due to the potential for heavy rainfall tonight over already saturated
  areas, a Flood Watch has been issued for the northwestern
  portions of the area.

- Additional chances of showers/storms will persist through the
  weekend into early next week.

- Warmer and more humid conditions will return next week, with
  heat indices rising to the 90s and near 100 degrees across the
  area.

&&

.SHORT TERM /THROUGH SATURDAY NIGHT/...
Issued at 225 PM CDT Fri Jun 5 2026

A lull in shower and thunderstorm activity was seen over the region
this afternoon, with a building warm frontal zone over the
MO/KS/NE/IA border. This front will act as a mechanism for
increasing shower and storm chances this afternoon and evening over
our northern areas. This afternoon, a capping inversion aloft will
help keep conditions largely, if not entirely, dry. We say that as
both 05.12z HREF/REFS ensembles show a few of their members with
some signs of cells development over 40 dBZ closer to the warm
front. However, most of the members keep us dry, so we went with
lower coverage (10-30% chance) for now. However, if a parcel/cell
does break through the cap, it could quickly become strong to severe
given significant instability (3000-4000 J/kg of SBCAPE per the
HREF). However, deep-layer shear appears to much weaker (only around
20 to 25 knots), so robust, organized convection appear unlikely,
which could result in more pulsey storms if any develop.

Looking at tonight, the signal is there for more widespread
convection along the boundary north toward Nebraska and Iowa. CAMs
have come into decent agreement with keeping this convection largely
out of our forecast area, although some of it may graze our northern
tier or two of counties as the instability gradient remains to our
north. SPC continues to keep a Slight Risk (level 2 of 5) of severe
storms along and north of Highway 36, but again, this could be more
of an isolated to scattered threat. Still, if any of the overnight
convection were to go any more southward, this could pose another
night of flash flooding where soil moisture is already saturated.
Heavy downpours are expected with any convection as Pwat values
around 1.5 to 1.7 inches are expected, which would be near or even
exceeding the 90th percentile of the NAEFS climatological
percentiles. That said, we have issued a Flood Watch from 7 PM this
evening to 7 AM Saturday morning for flash flooding potential.

As we look to Saturday and Saturday night, a building upper-level
ridge is expected over the central CONUS, but a southern stream
shortwave is expected to lift northeastward towards our region from
western TX. A leading wave of positive-vorticity advection ahead of
the mid-level low should provide ample large scale forcing over our
area, leading to potential for more showers/storms Saturday PM into
early Sunday morning, but this remains conditional with how storms
later tonight into Saturday morning evolve. SPC has maintained a
Marginal Risk (level 1 of 5) for strong to severe storms northeast
of the KC metro. Another very warm and humid day is expected
Saturday, with highs rising to the middle/upper 80s for most
locations.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Issued at 252 PM CDT Fri Jun 5 2026

By Sunday, a closed low will begin to lift across the central Plains
towards the northeast, and increase our PoPs through the day.
Forecast PWAT values still reside at/above the 90th percentile in
most deterministic guidance, with continued deep warm cloud layer
depths and long, skinny CAPE profiles. Deep layer shear looks to
remain marginal, so organized thunderstorms don`t look to be a major
concern for this day. Rather, continued heavy rainfall with
sub-severe wind/hail are expected to be the primary hazards
associated with the day`s activity. Considering current hydrological
concerns, and the continuation of those concerns tonight with
additional precipitation, will have to keep an eye on the potential
for excessive rainfall to expand hydrological concerns from where
rain has previously fallen farther east and south. This
expanded risk is highlighted nicely by WPC`s Day 3 ERO, where
our forecast area has been placed under a Slight (Level 2/4)
risk. Temperatures are forecast to fall slightly in conjunction
with this period of extended rainfall, which will be a brief
reprieve from the higher heat we`ve had (and will continue to
have) during the weekend.

This activity is expected to gradually push northeast as the
shortwave continues lifting farther northeast, gradually
decreasing PoPs through the day on Monday. There is a brief
opportunity for additional PoPs (40-60%) Monday evening with a
small perturbation trailing the retreating shortwave, but this
activity is expected to remain brief as a ridge builds over the
area starting midweek, keeping overall PoPs minimal through
midweek. Sustained southerly winds and continued warm/moist
advection will allow our heat indices to continue rising into
the 90s through the extended, with probabilistic guidance
indicating some low chances (15-30%) to meet or exceed 100 degF
during this period. Regardless of the potential for heat indices
to reach the triple digits, heat-related risks and concerns
will need to continue to be monitored as we grow closer to the
period in question, especially when these heat indices have the
potential to fall within our heat headline criteria. By the end
of the forecast period, synoptic guidance indicates an upper-
level trough and associated surface low potentially draping a
cold front across the northern Plains. This could serve as
relief from the intense heat forecast for next week, so this
forecast trend will also need to be monitored to see if it
sticks around.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 102 PM CDT Fri Jun 5 2026

SCT to BKN MVFR daytime cumulus clouds were seen across the
area early this afternoon. Models suggest that the ceilings will
improve quickly this afternoon to VFR, but current satellite
imagery shows pretty extensive BKN coverage over most of the
area, so thinking that these MVFR ceilings will continue for
longer than expected. Also, current observations show
southwesterly winds gusting around 20 to 25 knots at TAF
issuance, so plan to add gusts in as well. Largely dry
conditions are also expected per latest models, although there
is a lower chance (nearly 20-30%) of a storm developing near STJ
this evening.

&&

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

&&

$$

SHORT TERM...Schultz
LONG TERM...SPG
AVIATION...Schultz