Oakville, Missouri 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

808
FXUS63 KLSX 292302
AFDLSX

Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
602 PM CDT Thu May 29 2025

.KEY MESSAGES...

- Widespread light rain is expected to exit southeast Missouri and southwest
  Illinois by midnight, with isolated to widely scattered showers
  gradually diminishing further to the northwest.

- Moderating temperatures are expected Friday into early next
  week, with above normal readings (mid to upper 80s for highs)
  Sunday through midweek.


&&

.SHORT TERM...  (Through Late Friday Night)
Issued at 219 PM CDT Thu May 29 2025

Widespread light rain has impacted much of central and eastern
Missouri as well as south-central Illinois so far today. This area
of rain has been aided by low-level moisture convergence, low/mid
level frontogenesis, and mid/upper level diffluence ahead of the
trough axis. This area of widespread light rain is forecast to
gradually shift eastward, exiting parts of southeast Missouri and
southwest Illinois near or just after midnight. A rumble or two of
thunder is also possible late this evening, but better
instability should stay about 50-100 miles further to the south
along/south of the track of the surface low. Further to the
northwest, isolated to widely scatter showers and a few rumbles of
thunder are expected due to steep low-level lapse rates and the
aforementioned mid/upper level trough approach from the mid-
Missouri Valley. This activity should gradually wane with time due
to the loss of daytime instability as it heads southeast.

Dry weather is forecast late tonight with decreasing clouds from
northwest to southeast behind the mid/upper level wave. Lows in the
50s are expected, with the coolest conditions (low 50s) in parts of
central and northeast Missouri where at least some partial clearing
is expected before daybreak.

A partly to mostly sunny sky is expected on Friday along with
moderating temperatures. Low-level warm air advection increases
through the day from the northwest, with 850-hPa temperatures above
+12C advecting into eastern Missouri and western Illinois. Highs in
the upper 70s to near 80 degrees are forecast for a majority of the
area. While this would be some 10+ degrees warmer than this
afternoon, highs on Friday afternoon are still expected to be
slightly below normal for most locations.

A clear sky with mostly light northwest winds is forecast Friday
night as a surface ridge moves south through the southern Plains.
Northwest winds will help keep temperatures from dropping too much
along/east of the Mississippi River, with lows in the upper 50s to
near 60 degrees forecast. Parts of central and southeast Missouri,
particularly river valleys, should be several degrees cooler than
areas to the east due to lighter northwest winds. River valleys tend
to go light/variable in these setups, so some low 50s may occur in
these locations.


Gosselin

&&

.LONG TERM...  (Saturday through Next Thursday)
Issued at 219 PM CDT Thu May 29 2025

(Saturday - Monday Night)

The warming trend is expected to continue this weekend heading into
early next week as mid/upper level heights rise and 850-hPa
temperatures climb closer to +15C. Mostly dry weather is also
forecast during this time window, but we will continue to have to
keep an eye on a backdoor cold front. This boundary is likely to
make it at least near our south-central Illinois counties late
Saturday. Surface convergence along the front looks quite weak, so
any shower activity would be sparse, if any. Further west, dry
weather is even more likely as you head into Missouri.


(Tuesday - Next Thursday)

Ensemble guidance shows increasing variance for the middle of next
week with respect to the evolution of a western mid/upper level
trough. There is a pretty good signal that an impulse from the
longwave trough will eject out though the Plains sometime
Tuesday/Tuesday night, bringing a chance of showers and
thunderstorms to the region. Any specifics are difficult to
discern this far out however. The EPS mean moves this wave off to
the northeast with northwest flow aloft toward the end of the
forecast period while the GEFS mean keeps quasi-zonal flow aloft.
The difference is subtle, but the EPS would suggest a return to
drier weather along with slightly below normal temperatures while
the GEFS would keep chances of showers and thunderstorms going
near a stalled frontal boundary. Temperatures would also tend to
be a bit warmer, not as warm as earlier in the week but still
would tend to run at least slightly above normals for early June.


Gosselin

&&

.AVIATION...  (For the 00z TAFs through 00z Friday Evening)
Issued at 559 PM CDT Thu May 29 2025

The ongoing rain will continue to push east with it forecast to
exit the area completely late tonight. Additional showers with
embedded thunder are pushing southeast through west-central
Illinois and northeast Missouri. Impacts to terminals include
brief IFR visibilities. These are expected to weaken with time.
Winds turn out of the northwest tomorrow and elevate to around 10
kts areawide, lasting through the afternoon.

Jaja

&&

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

$$

WFO LSX