St. Joseph, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

876
FXUS63 KEAX 191141
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
641 AM CDT Sun Apr 19 2026

.KEY MESSAGES...

- Warmer today with highs in the upper 60s to lower 70s.

- Frost advisory tonight into early Monday morning for portions
  of NE Missouri.

- Well above normal temperatures expected Tuesday through
  Thursday with breezy south southwesterly winds.

- Next chance for showers and thunderstorms comes Thursday into
  Friday. Strong to severe thunderstorms may be possible
  Thursday afternoon into Thursday night.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 248 AM CDT Sun Apr 19 2026

Current H5 analysis shows a closed 506 dam low centered over NE
Ontario with longwave troughing extending southward into the
southeastern US, with our CWA situated on the western edge of
said troughing beneath 60 to 70 knot northwesterly mid/upper
flow. Meanwhile, at the surface, high pressure has built in,
with clear skies, nearly calm winds, and 3 AM temperatures
ranging from the upper 30s to the mid 40s. The aforementioned
trough will continue to move off to the east today, with
downslope flow and mid level height rises helping temperatures
this afternoon return to the upper 60s to lower 70s across the
CWA. Temperatures overnight tonight into early Monday should be
a bit warmer compared to those of this morning for most
locations except for NE Missouri, where low temps may range from
32 to 35 degrees. Thus, a frost advisory has been issued for
Putnam and Schuyler counties in NE MO from midnight tonight
through 9 AM Monday.

By Monday the eastern trough continues to move eastward, while a
relatively high amplitude mid/upper trough approaches the West
Coast, with ridging in between these two features building in
over the CWA from the west, yielding increased mid level
heights. Meanwhile, low level (850 to surface) flow will turn
south southwesterly as a warm front lifts north through the CWA,
bringing in some moisture return. This should result in high
temps for Monday afternoon a few degrees warmer than today`s
(low to mid 70s for most locations) and dew points increasing
from the 30s early Monday morning into the mid to upper 40s by
Monday evening. After a couple morning of relatively chilly
overnight temperatures, Monday night should feature temperatures
only dipping into the 50s.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
Issued at 248 AM CDT Sun Apr 19 2026

The warming and moistening trend is expected to continue into
Tuesday, with high temperatures forecast to rise into the upper
70s to lower 80s and dew points increasing into the mid 50s
Tuesday afternoon, along with 15 mph SW winds and gusts up to 25
mph. PoPs have trended downward, with only around 10% PoP across
NE MO Tuesday evening (better chances remain east of our CWA
into Central IL). The western mid/upper trough is projected to
enter into the western CONUS by Wednesday morning, reaching the
Intermountain West by Wednesday afternoon. Similar conditions
can be expected on Wednesday, with highs in the upper 70s to
lower 80s and breezy south southwesterly winds.

Guidance suggests the closed H5 low enters into the Northern
Plains by early Thursday afternoon, with associated troughing
extending southward into the Southern Plains and increased
southwesterly deep layer flow overspreading the CWA. Meanwhile,
a strong surface cyclone should enter the Dakotas by early
Thursday afternoon, moving eastward into the Upper Mississippi
Valley throughout Thursday afternoon and evening, with the
attendant southward extending cold front approaching the CWA.
Continued theta e advection should help dew points reach the
low to mid 60s by Thursday afternoon/evening, and with a plume
of 1000 to 1500+ J/kg of CAPE ahead of the approaching front
and around 30 to 35 knots of deep layer bulk shear, organized
updrafts capable of producing strong to severe storms will be
possible Thursday afternoon/evening/night. SPC`s latest update
has brought the Day 5 (7 am Thursday to 7 am Friday) 15% risk
area into almost the entire CWA. That being said, deep layer
shear is not particularly strong and model soundings at the
moment show relatively poor lapse rates and somewhat skinny CAPE
profiles, so we will see how things trend as we get closer to
Thursday. Models also show a plume of 1.3 to 1.5" PWATs ahead of
the front, which may promote locally moderate rainfall. WPC has
put almost the entire CWA within a marginal risk for excessive
rainfall. The most recent NBM run shows around a 30 to 40
percent probability for rainfall to exceed 1" across the KC
metro, with up to 60% probability of 1" or more of rain from
Butler to Boonville. The cold front should move through the
region sometime late Thursday night into Friday morning,
although models differ a little bit with the exact timing and if
the front completely pushes through the CWA or stalls out
somewhere within the CWA. PoPs linger through Friday afternoon
before clearing the region to the east by Friday evening/night.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 616 AM CDT Sun Apr 19 2026

VFR conditions are expected through the period under generally
clear skies. Light SW winds at the moment turn westerly by late
morning and increase to around 10 to 12 knots. Winds should
turn northerly by this evening and finally easterly by late
tonight, falling below 10 knots.


&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...Frost Advisory from midnight tonight to 9 AM CDT Monday for
     MOZ007-008.
KS...None.

&&

$$

SHORT TERM...BMW
LONG TERM...BMW
AVIATION...BMW