675
FXUS63 KLSX 110935
AFDLSX

Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
435 AM CDT Fri Apr 11 2025

.KEY MESSAGES...

- Areas of frost are likely tonight with lows in the mid to upper
  30s.

- Mainly dry weather is expected through the weekend with
  gradually warming temperatures.


&&

.SHORT TERM...  (Through Late Saturday Afternoon)
Issued at 340 AM CDT Fri Apr 11 2025

The latest radar mosaic and surface observations was showing light
scattered showers lingering across the area early this morning.
These showers were occurring along a cold front that extends
northwest across central Illinois into Iowa.  The latest run of the
HREF is showing this front undergoing frontolysis as it slowly
shifts to the southeast which should bring an end to the showers and
light sprinkles by mid morning.  The low clouds that is associated
with the front will likely stick around through midday which will
have an impact on temperatures, so have dropped going highs back by
a few degrees.

The HREF is also showing a large scale upper ridge building into the
area beginning late today through Saturday which will keep the area
dry.  There will be strong radiational cooling over the area late
tonight as a surface ridge will move into the area causing the winds
to turn light under clear skies.  Lows will drop into the mid to
upper 30s promoting areas of frost.

After the cold start on Saturday, the winds will turn out of the
south on Saturday under a sunny sky.  With almost full sunshine,
highs will be in low to mid 60s.

Britt

&&

.LONG TERM...  (Saturday Night through Thursday)
Issued at 340 AM CDT Fri Apr 11 2025

The cluster analysis is showing that there is overall good agreement
that a trough will drop down out of south central Canada into the
Midwest and Great Lakes Sunday into Monday.  The LREF is showing the
attendant cold front moving across the CWA on Sunday night, though
the 00Z NAM has it moving through the area slightly faster with
limited instability.  Will keep with isolated showers and
thunderstorms with the passage of this front late Sunday night into
Monday as system will be cut off from moisture by a high located
over the northern Gulf.

There will be another chance of showers and isolated thunderstorms
Wednesday into Thursday as the LREF is showing another trough
dropping down across Missouri and Illinois from the northwest.  30-
50% of the LREF members are showing a chance of showers mid to late
next week.

Sunday will be the warmest day ahead of the cold front (highs in the
70s and lower 80s) before highs drop into the 50s and 60s on Monday
and Tuesday.

Britt

&&

.AVIATION...  (For the 12z TAFs through 12z Saturday Morning)
Issued at 432 AM CDT Fri Apr 11 2025

Mainly dry conditions are expected through the period with
northerly winds at 10 knots or less. MVFR ceilings (1500-3000 FT
AGL)will move into all of the terminals by 15Z before moving out
between 16-20Z. Then VFR conditions are expected the rest of the
period.

Britt

&&

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

$$

WFO LSX