Mansfield, Illinois Weather Forecast Discussion

580
FXUS63 KILX 172302
AFDILX
Area Forecast Discussion...Updated Aviation
National Weather Service Lincoln IL
602 PM CDT Wed Sep 17 2025
.KEY MESSAGES...
- Hot and dry weather will continue until Friday, with daytime
  highs topping out in the upper 80s to lower 90s.
- A slow moving upper level low will bring chances (20 to 40
  percent) for showers and thunderstorms Friday night through
  early next week, along with a slight decrease in temperatures.
  Precipitation looks to be generally light.
&&
.DISCUSSION...
Issued at 203 PM CDT Wed Sep 17 2025
A slow moving upper level low pressure trough over the Plains will
slowly meander eastward into the Mississippi Valley region over the
next few days, prompting a pattern change that will result in a
modest increase in humidity and chances for scattered showers and
thunderstorms for a few to several days in central IL. Temperatures
which have been unseasonably warm will decrease a few degrees, but
any substantial cooling that would bring temperatures down to normal
(upper 70s highs) is not forecast through the upcoming 7 days. This
pattern shift looks to take place Friday into Saturday. Until then,
a very light easterly flow will maintain a dry air mass
characterized by dewpoints in the 50s, while periods of high clouds
and eventually some mid-level clouds increasingly encroach on
central IL. Highs should reach upper 80s to lower 90s daily until
Friday.
While overall the shear and instability appear to be on the weaker
side as this system moves in, occasional thunderstorms can be
expected, with minimal chances for severe storms. A stronger trough
is forecast by a few models to develop into the central U.S.,
potentially pushing a strong cold front into the region early to mid-
week next week, which could support severe thunderstorms.
While some heavier pockets of precipitation can`t be ruled out,
ensemble guidance points toward very low chances of enough
widespread precipitation to meaningfully change current drought
conditions. Ensemble probability of over a half inch through next
Thursday is around 60 percent, and over 1 inch is around 30 percent.
Two inch probabilities are generally under 10 percent. Put another
way, around a 60 percent chance of getting a decent lawn watering,
but under a 10 percent chance of significantly reducing our
drought status through the middle of next week.
37
&&
.AVIATION...  (For the 00z TAFs through 00z Thursday Evening)
Issued at 602 PM CDT Wed Sep 17 2025
VFR conditions will prevail at all TAF sites next 24hrs. Clear
skies expected through tomorrow with light and variable winds.
Auten
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$

NWS ILX Office Area Forecast Discussion