Old Jamestown, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

820
FXUS63 KLSX 111133
AFDLSX

Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
633 AM CDT Wed Mar 11 2026

.KEY MESSAGES...

- Showers and thunderstorms will gradually end from northwest to
southeast today as a cold front moves through the area.

- Cooler weather is expected today and Thursday with a slight
  warm- up toward the weekend.


&&

.SHORT TERM...  (Through Late Thursday Afternoon)
Issued at 359 AM CDT Wed Mar 11 2026

A line of thunderstorms continues to move east across the area early
this morning ahead of a cold front that currently extends from near
Chicago to Quincy to near Springfield.  These storms are continuing
to producing occasional near severe thunderstorm wind gusts as they
move through an environment with moderately strong instability and
strong deep layer shear. This line will continue to push to the
south and east this morning ahead of the cold front with CAMS
showing it moving out of the CWA by 12Z.  The cold front will be
slower to move across the area with the HREF not moving out the CWA
until 18Z, with the post frontal showers not clearing out of the
southern and eastern counties until mid afternoon.  Then dry weather
is expected tonight into Thursday as subsidence builds behind the
exiting upper trough.

With the clouds and the cold air advection behind the front today,
temperatures will be much cooler with temperatures mainly falling
through the day.  Skies will clear out tonight with a ridge moving
across the area setting up temperatures falling back to around 30
degrees for lows.  Highs on Friday will only be in the lower to
middle 50s.

Britt

&&

.LONG TERM...  (Thursday Night through Tuesday)
Issued at 359 AM CDT Wed Mar 11 2026

The dry weather will continue through Saturday as the LREF is
showing quasi-zonal flow across Midwest before a deep trough digs
into the the central CONUS early next week.  This has been
consistent with 60-80% of the LREF members producing precipitation
with this system with snow mixing Sunday night as the the trough
deepens.  Then the LREF and NBM is pointing toward dry weather for
Monday and Tuesday.

Highs will climb back into the 60s Friday into Sunday. Both the
deterministic and LREF 850mb temperatures are between -10C and -15C
on Monday which are below the 5th percentile for that date which
favors below normal temperatures early next week.

Britt

&&

.AVIATION...  (For the 12z TAFs through 12z Thursday Morning)
Issued at 556 AM CDT Wed Mar 11 2026

Rain will continue to affect UIN through 16Z, JEF/COU through 17Z,
and the St. Louis metro terminals through 18Z. There will will be
IFR ceilings at UIN/COU/JEF through 16-17Z with MVFR ceilings at
COU/JEF through 21Z, and at UIN and at the St. Louis metro
terminals through 03Z. Winds have already turned out of the
northwest behind a cold front at UIN/COU/JEF and will do so at the
St. Louis area terminals around 14Z with gusts to 25 to 30 knots
through early evening.

Britt

&&

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&

$$

WFO LSX