St. Joseph, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

138
FXUS63 KEAX 271110
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
610 AM CDT Tue Oct 27 2026

.KEY MESSAGES...

- Low chances (15-30%) for rain this morning and evening, with a
  brief cooldown in temperatures to the low 70s.

- Showers/storms anticipated (50-70%) across northern MO by
  Wednesday evening. Severe threat remains low with any
  activity.

- Low rain chances (15-30%) during the day Thursday, before
  increasing (40-60%) going into the weekend Friday/Saturday.
  Temperatures cool back down to the low 70s by Saturday.

- Wet, cool pattern continues through the end of the forecast
  period.

&&

.DISCUSSION...
Issued at 409 AM CDT Tue Oct 27 2026

Presently, a weak surface cyclone is situated over the NE/IA border,
with an attendant stationary front draped to the southwest towards
Salina. Weak synoptic ascent from a broad LLJ and moist flow over
the boundary is leading to light rain showers within the vicinity of
the boundary early this morning, intersecting far NW MO. RAP
sounding analyses show that this area still contains a stout layer
of dry air near the surface, so this narrow corridor of
precipitation will really need to work to moisten the near surface
layer before drizzle/light rain can manifest for these areas. Else,
chances of precipitation will gradually subside after sunrise as the
greater synoptic forcing from the surface low and passing shortwave
lifts off towards the northeast. Any momentum transfer towards the
surface from virga with passing showers will provide brief
opportunities for some localized gusts through the early morning.

At the larger scale, several shortwave disturbances are traversing
the periphery of synoptic ridging, which is broadly situated over
the eastern third of the CONUS. WV imagery shows a dense field of
cloud cover just upstream of KS/MO, which will lower overall solar
radiation during the daytime and help bring highs down to the low
70s across much of the forecast area. A developing shortwave off the
Rockies will enhance low-level WAA and broad synoptic ascent from a
strengthening LLJ, boosting additional low-end chances (10-20%) for
precipitation overnight tonight into tomorrow morning. The greatest
chances reside over eastern KS/western MO with this activity,
following the thermal ridge axis and the nose of the LLJ. As the
shortwave lifts along the periphery of the ridge to the northeast,
enhanced low-level WAA from strong south/southwesterly winds will
help temperatures rise back into the high 70s/low 80s across the
forecast area during the daytime. Additional moist advection along
this corridor will bring dewpoints to the low 60s. This will enhance
instability in advance of a cold frontal boundary draping
southeastward from the retreating surface low by Wednesday evening,
with MUCAPE residing around 1500 J/kg for portions of NW MO/NE KS.
With the primary forcing for ascent coming from the cold frontal
boundary, and building inhibition in advance of the front through
the evening, more factors are looking to work against the
probability of surface-based severe activity during this timeframe.
If showers/storms do initiate, they look to remain elevated through
the overnight period, with primary hazards of strong wind and hail
earlier in the period from steepening lapse rates out ahead of the
cold front. However, overall severe expectations continue to remain
lower with this activity.

As the cold front sags to the south, chances (15-30%) for
precipitation continue along that boundary through Thursday.
However, with a lack of significant synoptic forcing out ahead of
the boundary, chances will look to decrease during the daytime.
Temperatures behind the front cool back down to the low 70s, with
areas out ahead of the front remaining warmer in the high 70s/low
80s. Of course, with the prospect of any front that moves over our
forecast area, there could be some variation still in where exactly
temperatures will cool versus stay warm during the day Thursday. An
additional caveat will be the presence of any precipitation, as that
will additionally influence temperatures during the daytime. As of
right now, some signal in temperature spread exists around the US-
36/I-70 corridors through the LREF and NBM (~4-6 degF spread),
indicating there is some variability in current guidance that could
be better resolved in the coming days. For those of us who are
dreading the prospect of continued high temperatures in the 80s as
we approach the start of November, fear not! Your time for cooler
temperatures looks to come soon...

Weak ascent and WAA over the boundary will increase precipitation
chances (40-60%) yet again late Thursday/Friday, primarily
across northern MO. An upper trough lifting from the southern
Plains will keep precipitation chances around Friday into
Saturday, with temperatures trending down to the high 60s/low
70s by the start of the weekend. Increasing model divergence by
the weekend leaves some details a bit fuzzy at this time, but
greater agreement exists on weather drying out by late weekend
with a brief bout of amplified ridging at the synoptic level
before a deep trough pushes eastward by early next week,
increasing PoPs to close out the forecast period. Temperatures
remain on the cooler side to close out the forecast period with
increased precipitation chances.

&&

.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 607 AM CDT Tue Oct 27 2026

VFR conditions prevailing through the period. Winds remain
predominantly out of the S at 5-10 kts, with lowering cloud
ceilings by 16-18z this afternoon. However, these ceilings will
not impact flight categories. Winds shifting out of the SE by
3z, before shifting back out of the S by the end of the TAF
period. Low chance for iso/sct RA to impact terminals by the
end of the TAF period, but confidence remains low, so have left
out mentions for this issuance.

&&

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

&&

$$

DISCUSSION...SPG
AVIATION...SPG