Old Jamestown, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

729
FXUS63 KLSX 300824
AFDLSX

Area Forecast Discussion
National Weather Service Saint Louis MO
324 AM CDT Sat May 30 2026

.KEY MESSAGES...

- There will be several rounds of showers and scattered thunderstorms
  through Monday before drier weather is expected next week.

- High temperatures are expected to mainly be in the 80s.

&&

.SHORT TERM...  (Through Late Sunday Afternoon)
Issued at 323 AM CDT Sat May 30 2026

Surface winds were calm or very light over the area early this
morning to the north of a stationary front extending from the Mid
South into the Central Plains.  Low clouds and patchy fog with
visibilities below 1 mile have developed across parts of central and
southern Missouri.  HREF probabilities is showing that this same
area having >50% chance <1/4 mile visibilities between 4-8 am, so
will need to watch visibilities trends the next few hours for the
need of an advisory.

Water vapor imagery is showing a weakening upper trough along the
Mississippi River with a trough over the central Plains.  While the
first trough will continue to weaken and move off to the east this
morning, the band of low level convergence that has been across
southeast and central Missouri since yesterday will remain quasi-
stationary through tonight. RAP soundings are showing MLCAPES around
1500 J/kg with weak deep layer shear so I couldn`t rule out a few
storms producing small hail and gusty winds today. PWATS are around
1.9" with warm cloud depths above 10,000 feet, so locally heavy
rainfall will also be possible.

This activity will likely die down this evening but then pick up
again overnight as thunderstorms that develop over eastern Kansas
and western Missouri later today will move into central and
northeast Missouri after midnight.  Chances over this area will
initially be in the 40-60% range through early Sunday morning but
will fall off by late morning and Sunday afternoon as it moves east
of persistent area of convergence and instability.

Britt

&&

.LONG TERM...  (Sunday Night through Friday)
Issued at 323 AM CDT Sat May 30 2026

Model guidance has been consistent and is showing the upper flow
turning northwesterly and eventually northerly early next week as
the trough deepens over the East Coast.   The LREF is still showing
40-70% of is members producing rain over the CWA late on Sunday
night, likely as a shortwave trough or MCS moves southeast through
the area. The NAM/GFS is showing MLCAPES of around 1000 J/kg with
deep layer shear around 35 knots supporting a few strong storms
overnight along with the possibility for locally heavy rainfall. The
LREF has 30-50% of it members still producing rain into Monday
morning before mainly dry weather is expected on the backside of the
trough through Thursday.  High temperatures will be mainly in the
80s

Britt

&&

.AVIATION...  (For the 06z TAFs through 06z Saturday Night)
Issued at 1038 PM CDT Fri May 29 2026

KCOU and KJEF have the greatest chance of seeing impacts through
the TAF period. Ample low-level moisture thanks to repeated rounds
of showers and thunderstorms across central Missouri on Friday has
increased the potential for fog. Confidence is low on where the
worst of the fog will form, and there is a low chance for IFR
visibilities at KCOU and KJEF. Any fog that develops will
dissipate after sunrise, but our attention then turns to the
potential for showers and thunderstorms at KCOU and KJEF. Direct
impacts are uncertain, and while the current forecast calls for
afternoon timing, showers and thunderstorms could move over these
terminals during the late morning and/or early evening.

As for KUIN, KSUS, KSTL, and KCPS, confidence is high that VFR
flight conditions will prevail through a majority of the TAF
period. There is a very low chance that showers impact KSUS, KSTL
and/or KCPS during the afternoon, and whether or not they do so
won`t be clear until mid to late morning.

Elmore

&&

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

$$

WFO LSX