St. Joseph, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

713
FXUS63 KEAX 131828
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
128 PM CDT Sat Jun 13 2026

.KEY MESSAGES...

* Enhanced Risk (level 3 of 5) for severe weather on Saturday.
  All severe hazards are possible, including heavy rainfall.

* Quiet weather early next week, then chances for storms return
  midweek.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 128 PM CDT Sat Jun 13 2026

Remnant storms from this morning continue to work their way
across northern MO. These storms may still be capable of
producing severe weather, however, they should continue to
weaken with eastward extent.

A 500-hPa analysis shows zonal flow across the central CONUS
with a closed low in northern Ontario. At the surface, a cold
front extends through northwestern IA and eastern NE. Southerly
flow has allowed a relatively soupy airmass to return to the
area with temperatures in the mid-to-upper 70s and dew points in
the low 70s. Temperatures are expected to climb into the mid-80s
this afternoon, which, along with the plentiful moisture, will
allow MLCAPE values to soar to around 2000-3000 J/kg. Several
outflow boundaries are present near or in northwestern MO and
northeastern KS. The most notable of these is situated just
south of St. Joseph. The latest model guidance has seemed to
peg this area as the most likely location for convective
initiation this afternoon with storms initially taking a
discrete mode. Given deep layer shear values of 40+ kts, this
supports an initially supercellular storm mode with the primary
hazards of large hail and damaging winds. LCLs appear
unfavorable to tornado development, but certainly cannot rule it
out. As the cold front drops south into northern MO late this
afternoon and intersects these storms, convection is expected to
congeal into a more linear storm mode, which will pose a main
threat of damaging winds. As the evening progresses, the
environment will become more favorable for brief spin up
tornadoes along the line as the low-level shear increases with
the LLJ. Storms should be mostly out of the area by the time
this happens, but it is worth keeping an eye on. This thinking
aligns with the SPC Day 1 Convective Outlook, which has all of
western MO in an Enhanced (Level 3 of 5) Risk with damaging
winds and large hail being the primary concerns.

Timing wise, the most favorable timeframe for initial CI looks
to be around 3-4 PM CDT. As of 1 PM, attempts at CI are being
noted on satellite with showers forming along the
aforementioned outflow boundary. A weak cap is currently in
place around 900-hPa, which will need to be eroded before
storms can really take off. The front is expected to move into
northern MO around 5-6 PM CDT with a linear storm mode taking
over by 7 PM CDT. Storms should exit the southern portion of the
area by 1 AM CDT. However, a lot of uncertainty remains in this
forecast. The CAMs have not handled morning convection well
today and thus brings into question their output for this
afternoon and evening. But given the environment and current
convective evolutions, the picture painted above seems like the
most likely at this point.

The other important factor with the convection this
afternoon/evening will be the potential for flooding. Storms
should be fairly progressive, but given the amount of
precipitation that has fallen across the area over the past
week or so, it will not take a whole lot of additional
precipitation for flash flooding to occur. The current forecast
calls for 1-2" of new precipitation along and south of the
Missouri River with storms this afternoon/evening. Thus a flood
watch remain in effect for this area through 12Z on Sunday.

&&

.LONG TERM /SUNDAY THROUGH SATURDAY/...
Issued at 408 AM CDT Sat Jun 13 2026

Temperatures are expected to lower behind the cold front, with highs
in the low/mid 70s. The upper-level trough is expected to cycle
around the Hudson Bay, and generally place much of the forecast area
under zonal flow on Monday before several shortwave disturbances
will traverse the upper-level flow and place the forecast area under
multiple rounds for precipitation. The first of these rounds appears
Tuesday afternoon/evening, with a weak boundary invigorating
scattered chances (15-30%) for precipitation. By Wednesday
afternoon, another upper-level trough and associated surface low
will increase chances (40-60%) of precipitation through the evening
and overnight along another boundary. Temperatures this day will
climb ahead of strong surface-based southerly flow, with forecast
highs reaching the mid/high 80s. The boundary may slow/stall through
Thursday, prompting precipitation chances to continue mostly
along/south of the I-70 corridor. By the end of the forecast period,
brief amplified ridging to the west keeps remaining PoPs lower.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1219 PM CDT Sat Jun 13 2026

The primary concern through the TAF period continues to be the
chance for storms this afternoon and evening. An outflow
boundary has pushed through KSTJ resulting in northerly winds,
however, expectation if for the boundary to surge back north
over the next couple of hours, so have opted for prevailing
southerly winds in all four of the TAFs. Most confident timing
for storms this afternoon/evening is 00Z to 03Z at KMCI and
KMKC (an hour earlier and later at KSTJ and KIXD respectively).
There is a chance for isolated storms this afternoon,
particularly at KSTJ, however, confidence in timing and
location is not high enough to include any mention in the TAFs.
MVFR CIGs are expected to accompany the storms this
afternoon/evening, with the lower CIGs lingering for a few
hours after precipitation ends before lifting and clearing
through the morning tomorrow. Winds will flip to northerly with
the cold frontal passage and storms this evening.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...Flood Watch through Sunday morning for MOZ028-029-037-038-
     043>045-053-054.
KS...Flood Watch through Sunday morning for KSZ057-060-103>105.

&&

$$

SHORT TERM...Carothers
LONG TERM...SPG
AVIATION...Carothers