El Vista Illinois Weather Forecast Discussion

968
FXUS63 KILX 130507
AFDILX
Area Forecast Discussion...Updated Aviation
National Weather Service Lincoln IL
1207 AM CDT Mon Oct 13 2025
.KEY MESSAGES...
- While significant drought alleviation is not expected, rain is
  in the forecast for central and southeast Illinois by next
  weekend.
&&
.UPDATE...
Issued at 854 PM CDT Sun Oct 12 2025
Scattered light returns are evident on radar moving into west-
central IL in the vicinity of a weak warm frontal boundary. While
the air mass ahead of these returns is quite dry, characterized by
upper 40s dewpoints in the middle of the forecast area, dewpoints
climb toward the boundary to lower 50s in west central IL, and
into the lower 60s in the warm sector over northern MO and
southern IA. Satellite derived precipitable water also shows this
gradient in moisture, with PW around 0.7 inches in central IL to
1.5 in the warm sector. Returns have been eroding heading into IL
this evening, but with time at least some spotty showers should
edge eastward into the forecast area, and finally have seen a
report of rain at the surface approaching Schuyler County. Have
added slight chance precipitation in Schuyler, Fulton, and Knox
Counties prior to midnight, slowly spreading east through the
Illinois River Valley overnight. Otherwise, low temperatures from
the afternoon forecast package, ranging from upper 40s in eastern
IL where cloud cover should be minimal overnight, to upper 50s in
western IL where cloud cover and light breezes should limit
temperature falls.
37
&&
.SHORT TERM...(Tonight through Monday)
Issued at 219 PM CDT Sun Oct 12 2025
18z/1pm surface analysis shows a 988mb low over southern Manitoba
with a cold front extending southward into the Plains. As this
front pushes slowly eastward, it will intercept limited Gulf moisture
to produce a band of clouds and scattered light showers west of
the Mississippi River tonight. Forecast soundings initially show
a very dry environment across central Illinois:however, as the
boundary nears and the profile moistens from the top-down, clouds
will increase/lower across the western KILX CWA after midnight.
Several CAMs show weak radar reflectivity spilling into the
Illinois River Valley before daybreak. Given the very dry boundary
layer, think it will take some time before any precip is able to
reach the ground. Based on NAM/RAP soundings, have opted to add
isolated showers to the forecast along/west of the Illinois River
between 06z/1am and 11z/6am. As the band of very light showers
shifts further eastward over the parched soils of central
Illinois, the precip will gradually dissipate by mid-morning. Have
included slight chance PoPs as far east as I-55 between 12z/7am
and 15z/10am, but think the showers will dry up thereafter. Any
rainfall that occurs will be quite light, amounting to only a
couple hundredths of an inch at best. The remainder of the day
will feature partly to mostly cloudy conditions west of
I-55...with mostly sunny skies further E/SE. Low temperatures
tonight will range from the middle 40s near the Indiana border to
the upper 50s west of the Illinois River. Highs on Monday will
climb into the middle to upper 70s.
Barnes
.LONG TERM...(Tuesday through Next Sunday)
Issued at 219 PM CDT Sun Oct 12 2025
A mostly uneventful work week lies ahead as central Illinois
remains under the influence of prevailing upper-level ridging.
After a slight cool-down into the lower to middle 70s on
Wednesday, readings will climb back into the upper 70s and lower
80s by Friday. After that, the weather gets a bit more interesting
as a cut-off low progged to form over northern California on
Monday gradually opens and lifts northeastward by the end of the
week. As this process unfolds, deep-layer southwesterly flow will
develop ahead of the feature across the Plains/Midwest. This will
help pull better moisture into the region and result in a more
significant chance for rainfall from Friday night through Sunday.
The big question is of course how much rain will occur. Synoptic
models often handle antecedent dry soil conditions quite poorly,
so raw QPF from any model at this point should be taken with a
grain of salt. In addition, there are still some minor timing
discrepancies among the various solutions...so it is still to
early to pinpoint exact numbers. With that said, general consensus
suggests showers and perhaps a few thunderstorms pushing into the
Illinois River Valley late Friday night...with a re-development
of showers/storms mainly east of I-55 Saturday afternoon/evening.
It therefore appears reasonable to surmise that the most substantial
rainfall will materialize Saturday afternoon across the far E/SE
CWA. The 12z NBM supports this general theory...showing a 40-50%
chance of greater than 0.50 rainfall east of I-55...and around a
30% chance of over 1 inch south of I-70. This scenario may change
slightly over the next few days, so please refer to later
forecasts for further details.
Barnes
&&
.AVIATION...  (For the 06z TAFs through 06z Monday Night)
Issued at 1207 AM CDT Mon Oct 13 2025
Surface high pressure will shift east, causing winds to veer to
a more southerly direction mid to late morning. However, the
gradient will weaken across the region by early to mid afternoon,
causing winds to go light and fickle. Tonight, a weak front
dropping south will result in a yet another wind shift, with winds
blowing gently from the northeast behind the front. A weak upper
level disturbance rippling along that front will bring prolific
cloud cover to the region, but guidance suggests a high likelihood
(80% chance) that will be in the VFR category with model
forecasts averaging ceiling heights around 4500-6000 ft.
Bumgardner
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$

NWS ILX Office Area Forecast Discussion