St. Joseph, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

991
FXUS63 KEAX 262326
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
626 PM CDT Sun Apr 26 2026

.KEY MESSAGES...

- Rounds of showers and thunderstorms are expected tonight into
  tomorrow. Severe weather in the form of damaging straight
  line winds, large hail, and possibly a brief tornado or two
  can be expected tonight. The multiple round of rain could also
  lead to flash and river flooding.

- Drier and cooler conditions are expected Tuesday into the
  weekend.

&&

.DISCUSSION...
Issued at 211 PM CDT Sun Apr 26 2026

Cluster of storms that developed near Hays KS this morning has
continued to evolve into a bow echo racing across eastern KS.  Meso-
analysis from SPC suggests storms are building into increasingly
unstable environment with 1500-2000 J/kg of surface based CAPE with
~40 knots of 0-6 km bulk shear. As mid level winds increase through
the late afternoon hours, expect bulk shear to increase closer to 50
knots.  With storms becoming increasingly surface based as they
build into the area, expect increased wind threat. Warn on forecast
has increased the 1"+ hail threat across Linn KS ~21Z this afternoon
with southern end of the line, and a more widespread wind threat
increasing after 21Z ahead of the line.  Precipitable water is
running  in the neighborhood of 1.3", well above the 90th percentile
for this time of year.

After the initial line pushes east across the area, could see
additional development behind the line as additional mid level short
waves build east and 30-40 knot low level jet develops.  Inflow into
the region could be shifted a bit by potential outflow from initial
line of storms. HRRR has hinted at this potential over the last few
hours, leading to additional development and training of storms
along the I-70 to highway 50 corridors. Given this potential and
antecedent wet conditions, have expanded the flood watch to include
much of the forecast area tonight. Additional storms tonight could
be strong given the steep lapse rates from 800-700 mb (potentially
exceeding 8 degrees C/km) in combination strongly sheared
environment. Upper level divergence increases after 06Z tonight and
continues Monday morning as left exit region of upper level jet
noses into the area.  Overall, you can see trends in the models of
multiple rounds of storms overnight, but specific timing is
difficult to ascertain at this point.

Strongly sheared and unstable environment continues tomorrow morning
as warm front races north across the area.  As such, could see a
brief recovery in temperatures through the morning hours with
surface temperatures climbing into the 70s, but environment
doesn`t appear to be all that strongly capped so could be
looking at potential for additional storms until cold front
shifts through the region in the late morning/early afternoon
hours.

Cooler and drier conditions are expected much of the remainder of
the week, which are well needed.

&&

.SHORT TERM /THROUGH MONDAY/...
Issued at 622 PM CDT Sun Apr 26 2026

Low confidence forecast with weakly capped and unstable
atmosphere remaining across the area through the overnight. Used
the 22Z HRRR to try to concentrate thunderstorm mention at the
individual TAF sites, as forecast soundings indicate a storm is
possible at nearly any point throughout the night. Expect MVFR
ceilings through much of the night into Monday morning,
potentially seeing some partial clearing behind cold front
after 16Z Monday.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...Flood Watch through Monday evening for MOZ001>008-011>017-
     020>025-028>033-037>040-043>046.
KS...Flood Watch through Monday evening for KSZ025-057-102>105.

&&

$$

DISCUSSION...BT
AVIATION...BT