Area Forecast Discussion
193
FXUS63 KLSX 221950
AFDLSX
Area Forecast Discussion
National Weather Service Saint Louis MO
150 PM CST Sat Nov 22 2025
.KEY MESSAGES...
- Another storm system will bring light rain to the area Monday
afternoon Monday night ahead of a cold front. Behind the front,
slightly colder than normal temperatures and dry weather is
expected through the Thanksgiving holiday.
- Even colder air is possible beyond the official forecast late
next weekend. The pattern suggests at least some threat of
wintry precipitation late next weekend into the first week of
December, but it`s too early to ascertain any additional detail
at this time.
&&
.SHORT TERM... (Through Late Sunday Night)
Issued at 121 PM CST Sat Nov 22 2025
Stratus has finally had more of a southwestward push this
afternoon, allowing for sunshine to warm temperatures into the 50s
this afternoon in most areas, with 40s hanging on where stratus
has been persistent (western IL and central/southeast MO).
A weak cold front will move through the region tonight into early
Sunday morning. The latest guidance, particularly the RAP, shows
fairly high low level moisture in the 925mb layer and below.
Therefore, this lingering moisture and subtle low-level lift
should allow for additional stratus/fog development tonight into
early Sunday morning, especially in areas that did not mix
efficiently this afternoon. Have upped cloud cover and low
temperatures to account for this.
Drier air should filter into the low-levels on Sunday, allowing
for skies to go partly cloudy. Therefore, temperatures into the
mid 50s/low 60s seem reasonable.
Deitsch
&&
.LONG TERM... (Monday through Next Saturday)
Issued at 121 PM CST Sat Nov 22 2025
A shortwave will push toward the region on Monday. The latest
deterministic/ensemble guidance suggests the mid/upper forcing
will be enough for widespread rain Monday afternoon into Monday
night, departing through Tuesday morning. Fortunately, any
appreciable instability looks to stay well south of the CWA, thus
no severe weather, or even thunder, is expected with this system.
High pressure spills into the region Tuesday through Thursday
which should bring a period of tranquil weather, albeit a little
cooler than normal (temperatures in the 40s).
Precipitation chances will ramp up once again next weekend,
particularly Saturday and beyond as a trough digs into the western
CONUS, putting the Midwest in southwest flow aloft. While rain
looks the most likely through the official forecast period,
ensemble guidance is suggesting at least some threat of wintry
precipitation late next weekend into early next week as an early
Arctic airmass spills into the Plains and Upper Midwest beneath
the more active southwest flow aloft. Details are obviously low at
this point and guidance is not going to give the resolution
needed to resolve individual waves in this pattern this far out in
time, but there is at least a threat from Sunday and beyond. This
is something we will continue to monitor through the upcoming
week!
Deitsch
&&
.AVIATION...8Z TAFS THROUGH 00Z MONDAY/...
Issued at 1139 AM CST Sat Nov 22 2025
Challenging TAF forecast on track for this afternoon and again
overnight. Confidence is high in a period of VFR for the metro
St. Louis TAFs, as pesky stratus has finally moved to the south
and mixed out. Have stuck with IFR stratus longer at
UIN/COU/JEF, but think with time all sites will see at least
some VFR into late this evening.
Confidence then deteriorates tonight with potential reformation
of fog/stratus. Have gone the most pessimistic at UIN/COU/JEF,
where limited mixing today will mean it won`t take much to get
renewed fog/stratus. However, IFR restrictions are certainly
possible in metro St. Louis as well and this will be re-
evaluated for the 00Z issuance. With an incoming weak front,
leaned more towards IFR stratus formation. Winds will be fairly
light and variable through the period.
Deitsch
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
NWS LSX Office Area Forecast Discussion
