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FXUS63 KILX 141707
AFDILX

Area Forecast Discussion...Updated Aviation
National Weather Service Lincoln IL
1107 AM CST Fri Nov 14 2025

.KEY MESSAGES...

- Near record warm temperatures are forecast through tomorrow for
  much of central and southeast Illinois. There is an 80% chance
  that high temperatures exceed 70 degrees today south of I-74 and
  tomorrow south of a roughly Beardstown to Danville line.

- The next opportunity (60% chance) for precipitation arrives
  Monday into Tuesday. There is a low (20%) chance that rain
  mixes with or changes to snow north of a roughly Macomb to Paris
  line Monday evening or Monday night.

&&

.DISCUSSION...
Issued at 222 AM CST Fri Nov 14 2025

Early Friday morning, water vapor satellite indicates ridging across
North America`s midsection, with a pair of upper level lows in the
west: one off the California Coast and the other centered in
Alberta. The northern of these two features will bring a (most
likely dry) cold front through our area on Saturday, while the
southern low will send some mid-upper level energy our way in the
way of one or more shortwaves featuring some precipitation
chances early-mid next work week.

***** NEAR RECORD WARMTH TODAY AND TOMORROW *****

The combination of mostly clear skies, a seasonably dry airmass in
place, and south-southwest return flow will culminate in near-record
warm temperatures this afternoon. Forecast temperatures, blended
slightly to the HRRR to account for anticipated deep mixing, range
from near 70 north of I-74 to the mid 70s southwest of a roughly
Macomb to Effingham line. Tomorrow, more uncertainty comes into the
high temperature forecast because, despite a warmer start due to
clouds and warm air advection (WAA) overnight (lows in the mid-upper
50s), cloud cover will be over the area most of the day and the cold
front is slated to sweep some portions of the area before peak
diurnal heating. The highest temperatures (mid 70s) will likely be
near and south of a roughly Havana to Danville line, corresponding
to the cold front`s approximate position at 19z/1pm (this was
approximated by analyzing the position of the maximum in HREF thetaE
spread at that time). A few CAMs depict some sprinkles with the WAA
early tomorrow morning, though in general the probability of
measurable rainfall is less than 20%. Expect southwest winds
gusting to 25-30 mph (highest in east-central IL) ahead of the
front mid Saturday morning into early afternoon, a lull in winds
with the front, and then northwest winds gusting to 20-25 mph
during the evening as the gradient re-tightens.

***** COOLER SUNDAY, PRECIP CHANCES EARLY NEXT WORK WEEK *****

Cold advection is slated to bring temperatures back into the 30s
(50-60% chance) north of a Beardstown to Danville line Sunday
morning, with afternoon highs running in the mid 50s - near normal
for mid November. Forecast confidence decreases Monday into
Tuesday as one or more shortwave disturbances lift out of the
Desert Southwest and move across the Middle Mississippi Valley and
Midwest. The Monday afternoon-night period is our greatest
concern at this time, with the strength, meridional (i.e., north-
south) position, and timing of the trough each dictating
precipitation types (p-types) and amounts. A stronger (weaker) low
would translate to more (less) precipitation but could also
feature a better (weaker) push of WAA which would favor most/all
rain (some snow) as a p-type. A further north (south) track would
also favor warmer (cooler) temperatures and all rain (some snow).
A nocturnal (diurnal) low and precipitation arrival would feature
warmer (cooler) low level temperatures and hence a higher
probability of all rain (some snow). Right now, only about 20-30%
of the Low Resolution Ensemble Forecast (LREF) system members have
any snowfall north of a roughly Macomb to Paris line, while most
of the other members give us rain (a few are dry). NBM suggests
the chance of widespread precipitation amounts sufficient to put a
dent in the drought is low; in fact, its probability of more than
a half inch ranges from roughly 10-15% in Galesburg to 30-40%
south of I-70. Stay tuned to the forecast as we monitor the
(currently low) potential for snow with this system.

Confidence remains low in the forecast Tuesday and beyond as global
models and their respective ensembles suggest a continued active
pattern with a 200mb jet streak shifting from the Southern Plains
into the Ohio Valley midweek. By late in the week, as that upper
level jet streak shifts northward into the Great Lakes and we find
ourselves near its right entrance region - a favored location for
surface cyclogenesis - confidence falls even further. For
example, NBM`s interquartile range (IQR) for max temperatures
spans 46 to 63 degF in Lincoln by Thursday. That is to say, there
is a 50% chance the high temperature will lie between 46 and 63
degF and a 50% chance it will land outside of that range; stated
differently, the probability that Thursday`s high temperature is
between 46 and 63 degrees is equal to the probability that it is
either less than 46 or greater than 63. Precipitation chances also
increase from Wednesday night into Friday, with NBM giving the
area a generous 60-70% chance of rain during that time. We`d like
to stress that this doesn`t mean it will be raining that entire
time, just that the chance is high (>60-70%) that it will rain at
some point late week; models will likely take a few days before
they pin that more narrow timeframe down.

Bumgardner

&&

.AVIATION...  (For the 18z TAFs through 18z Saturday Afternoon)
Issued at 1056 AM CST Fri Nov 14 2025

A cold front will approach the regional terminals from the north
late tonight into Saturday. Winds will become breezy overnight.
Despite a stout low-level jet veering in across the region, a
stable near-surface environment should preclude gusts exceeding 25
kts through the overnight period.

Clouds will lower ahead of the impending cold front. We anticipate
VFR ceilings persisting through this TAF cycle, though some
lowering near MVFR is a possibility beyond 09z. There is currently
a 50% chance of ceilings falling into the MVFR category by then.
One notable exception is at KCMI, where there is a 50% chance of
ceilings falling into the IFR range just after 12z.

MJA

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$