St. Joseph, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

379
FXUS63 KEAX 121133
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
633 AM CDT Sun Apr 12 2026

...12z Aviation Update...

.KEY MESSAGES...

* Active weather pattern continues across the region, through the
  weekend and into at least the middle of the work week

  - A river and areal flood threat will continue during this time,
    often relying on overlapping moderate to heavy rain events.

* Showers and non-severe storms overspread the area this morning
  into this afternoon before clearing out.

  - A localized flooding threat is possible, but unlikely with most
    areas anticipated to receive an inch or less of rain.

* Severe storm threat Monday is very low with better
  chances/opportunities Tuesday and Wednesday.

&&

.DISCUSSION...
Issued at 413 AM CDT Sun Apr 12 2026

After a couple/few scattered storms Saturday evening over portions
of N/NE Kansas, SE Nebraska, and NW Missouri, conditions trended
quiet into the overnight. Currently over the area, GOES Nighttime
Microphysics product depicts pockets of mostly clear skies as
remnant shower activity continue to erode and drift NE through the
area. Looking to the SW, can clearly see the next in the series of
weather makers moving up through the Southern Plains on various GOES
products, including aforementioned Nighttime Microphysics and WV
products among others. Regional radar mosaics too show the broad
area of precipitation beginning to lift out of Oklahoma and into
south-central Kansas at this time. Much of the rest of the overnight
will remain quiet for the area responsible shortwave and deep
moisture plume continue to build NE toward the area. CAM/Hi-res
guidance has tended to slow down the initial precipitation onset,
now appearing most likely after 12z for western portions of the
forecast area. The SE trend in precipitation has become more stable,
resulting in the corridor of greatest chances approximately along a
line from the KC Metro, up I-35 into Iowa and areas to the S and E.
While there are a few favorable ingredients for a flooding threat,
including climatologically high PWats, strong moisture advection,
and prolonged precipitation potential, there is limited/low overall
concern. Primarily driven by very weak to nil CAPE (limiting rain
rates) within the broad WAA/isentropic lift. HREF PMM and recent
HRRR runs suggest some stripes of >1" possible, but most areas under
that. So, some ponding in prone areas and stream/river rises are the
most likely scenario. Otherwise, a mostly dreary daytime period.

Conditions dry out Sunday evening and into the overnight as a degree
of mid-level ridging/height rises traverse the area. Concurrently,
next approaching shortwave coming off the SW CONUS trough will begin
to build low pressure off the Colorado Front Range and to the NW of
the immediate area. This will help yield a VERY STRONG capping
inversion over the area throughout Monday. Without any notable way
to overcome the CAP, new SPC Day 2 Outlook unsurprisingly has taken
the area out of the Marginal risk. Fortunate, given the profiles
otherwise being quite supportive of organized storms.

The potential for any strong to severe storms continues to be
greater on Tuesday. While CAP magnitude may be similar to Monday,
warmer surface temps and diurnal mixing likely to yield a very
weakly inhibited environment by mid-late afternoon. Though, much of
the area is likely to be within warm sector that would tend to
require shortwave or other focused lifting mechanism. There tends to
be no clear shortwave depiction, which would then suggest our most
likely scenario is upscale growth from initiation in eastern Kansas
and NE Oklahoma. Regardless, the environment will be supportive of
organized and strong convection with steep mid level lapse rates
(>1500-2000 J/kg CAPE), >35-40 kts deep shear, etc. Tend to see
hail/wind threat as the primary given lean towards upscale growth
scenario for the area. See SPC Day 3 Slight Risk and discussion as
well.

As the western trough finally begins to kick out into the Plains,
Wednesday may see another strong/severe threat across the area.
Attendant surface low will begin to move across Nebraska/Iowa
through the day, dragging a surface front into the area by the
afternoon. Main uncertainty here will be any ongoing/persistent
precipitation and cloud cover. Deterministic synoptic guidance shows
off/on or semi-persistent QPF from Tuesday evening through
Wednesday. So, how much can or will the environment be able to
recover before the surface front and mid-upper trough reach the area
Wednesday afternoon/evening? Should the environment recover
sufficiently, this could be our all modes risk. Or, could just be
messy weaker convection much of the day. The SPC Day 4 15% is
certainly reasonable given the potential and uncertainty.

Phew, at least a brief break Thursday as the upper trough kicks east
and front passes through the area. However, another western trough
begins to dig down the coast at this time and guidance suggests a
progressive passage through the Mountain West. This potentially
yields renewed shower/storm activity by Friday evening and into
early portions of next weekend.

Aside from cooler temperatures during and immediately after
precipitation, persistent southerly flow/WAA to keep the area near
and above seasonal norms throughout the forecast period. Expect
highs often in the upper 70s to mid 80s.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 628 AM CDT Sun Apr 12 2026

Initially VFR conditions will degrade to at least MVFR
conditions this morning and continue into the early-mid
afternoon. Potential for IFR ceilings, however upstream
observations do not currently show an expansive IFR cloud deck.
Rather, a predominantly low MVFR deck, so have opted to keep
this issuance low MVFR. Improvement back to VFR quickly mid-late
afternoon. Winds remain gusty out of the SSW from current
through around 00z, generally around 15 to 20 mph sustained and
gusts to around 30 to 35 mph. Possible to briefly tap into lower
portions the LLJ before it eases, which could yield gusts toward
40mph before mid-morning.

&&

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

&&

$$

DISCUSSION...Curtis
SHORT TERM...SPG
LONG TERM...SPG
AVIATION...Curtis