St. Joseph, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

231
FXUS63 KEAX 090436
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1136 PM CDT Fri May 8 2026

.KEY MESSAGES...

* Light rain to gradually taper off over the next several hours.

* Marginal risk of severe storms in the far southern and
  southeastern portions of the CWA this afternoon. The
  strongest storms could produce hail and severe wind gusts.

* Warm on Saturday before chance (30-40%) of rain in the
  evening and overnight into Sunday.

* Cooler temperatures Sunday before a warming trend heading
  into next week.

&&

.SHORT TERM /THROUGH SUNDAY NIGHT/...
Issued at 305 PM CDT Fri May 8 2026

Intermittent light rain has been noted across the area this morning
and early afternoon, particularly along and north of US-36. ACARS
soundings from KMCI continue to depict a modest layer of dry air
near the surface; this has been largely responsible for the limited
amount of rain actually able to reach the surface. As of 18Z,
several stations have reported only a trace of rainfall, including
KSTJ which had several pockets of 25-35 dBZ reflectivities move over
the airport. These showers continue to be compressed southward ahead
of a weak cold front.

Recent mesoanalysis has indicated increasing low-level moisture
south of I-70 within the last several hours. This trend is expected
to continue through much of the afternoon courtesy of southwest
surface and low-level flow drawing in Gulf moisture. With the
introduction of additional moisture has come increased instability
Between 16Z and 19Z, around 400-600 J/kg of SBCAPE had been advected
into eastern Kansas and western Missouri south of I-70. This
destabilization trend has generally met expectations, with model
analysis suggesting a nearly 100% chance of >500 J/kg SBCAPE by 18Z
in our far southeastern KS counties and southern MO counties.
Indeed, it does appear that there is at least slight instability
present in the southern portions of our CWA with some potential (50-
80%) to become moderately unstable by mid-afternoon.

Storms are expected to develop within the next few hours across
southern portions of the CWA, taking advantage of the greater
instability and ~45 kts of effective bulk shear. For reasons such as
these, far southern and southeastern portions of the CWA have been
included in a marginal risk for severe weather this afternoon. The
strongest storms could produce hail and severe wind gusts. Overall,
however, the severe threat remains low. Guidance has consistently
indicated upscale growth should occur quickly after initiation as
the cold front nears. Storms ahead of the front are expected to
fully exit the southeastern portion of our CWA by 9PM. Some CAMs
have resolved post-frontal convection, perhaps by tapping into
lingering instability. Confidence in this potential, however, is
quite low. While some instability may remain, inhibition will
increase dramatically in the wake of the front, reducing the ability
for storms to fire. If post-frontal convection occurs, it would
likely be elevated in nature and struggle to become strong/severe.

Behind the front, overnight lows will drop into the mid/low 50s with
roughly a 40% chance of falling into the upper 40s in northern
Missouri. Westerly/southwesterly surface flow will also quickly
return behind the front as low level high pressure builds to our
southwest and low pressure nears from the northwest. It was a nice
try, Cold Front, but this pattern will provide plentiful warmth and
sunshine for much of the day on Saturday with temperatures climbing
into the upper 70s and even low 80s. But alas! Cold Front makes a
return Saturday evening, this time with a more lasting impact. A
shortwave aloft will provide some lift ahead of the front, but with
very little instability and dry low-level air for much of the day,
it is unlikely to amount to much more than some rain showers and
maybe some rumbles of thunder. The vast majority of the area will
have a 30-40% chance of precipitation at any given time between
Saturday evening and early Sunday morning, with probabilities
decreasing from the north as the front progresses south. This time,
Cold Front makes its mark, leaving us with Sunday maximum
temperatures in the upper 60s and low 70s.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
Issued at 305 PM CDT Fri May 8 2026

The foreseeable future continues to be dominated by an upper-level
ridging pattern. There is potential for another cold front to move
through on Tuesday. Given the relatively slow moving nature of this
boundary, there should not be much of an impact on Tuesday outside
of some low-end (15-20%) rain chances in our far northeastern
counties. Instead, widespread cooler temperatures (albeit only ~5
degrees cooler) will take hold on Wednesday with prevailing
northerly surface flow. On Thursday, surface winds will shift out of
the south/southeast, once again increasing temperatures. In fact,
there is roughly a 30-50% chance of reaching 90F on Friday, mainly
in the western portions of the CWA.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 1136 PM CDT Fri May 8 2026

VFR conds will prevail thru the TAF pd as clr skies are expected
thru 14Z-15Z aft which incr high clouds area expected. Aft
00Z-02Z ovc mid-lvl clouds around 10kft are fcst to impact the
terminals. Winds to begin the TAF pd will be out of the SW btn
5-10kts. Aft 14Z-15Z wind will incr to around 10kts (at STJ
winds will incr to nr 15kts with gusts 20-25kts) while remaining
out of the SW/WSW. Aft 21Z-22Z...winds will shift to the west
btn 5-10kts as a cold front moves thru the TAF sites. Aft
01Z-02Z winds will shift to the north and remain btn 5-10kts.
The main concern for aviators will be the potential for showers
and thunderstorms at the TAF sites aft 00Z however, at this time
the chc are too low for a prob30 grp.

&&

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

&&

$$

SHORT TERM...Macko
LONG TERM...Macko
AVIATION...73