Cooperstown, Illinois Weather Forecast Discussion

501
FXUS63 KLSX 301916
AFDLSX
Area Forecast Discussion
National Weather Service Saint Louis MO
216 PM CDT Tue Sep 30 2025
.KEY MESSAGES...
- Warm and dry weather will continue at least through Monday.
&&
.SHORT TERM...  (Through Late Wednesday Night)
Issued at 215 PM CDT Tue Sep 30 2025
A high amplitude blocky pattern continues to dominate the weather
across the CONUS.  The strong upper level ridge over the Mississippi
Valley continues to keep the weather warm and dry for our region.
The ridge will drift eastward and attenuate somewhat through the
short term, but this will have little effect on sensible weather at
the surface. Overnight lows tonight will drop into the 55-60 degree
range again in most locations due to the dryness of the air and good
radiational cooling conditions.  Highs Wednesday should be a couple
of degrees cooler as the ridge axis will be east of the Mississippi
Valley and there will likely be more cloud cover, although a 2-3
degree drop in temperatures will barely be noticeable.  Lows
Wednesday night will likely be a bit warmer in the upper 50s to
low 60s due to the increased cloud cover and weak southerly flow.
Carney
&&
.LONG TERM...  (Thursday through Next Tuesday)
Issued at 215 PM CDT Tue Sep 30 2025
The warm, dry weather will continue through the weekend into early
next week.  The mid-upper level pattern will slowly modify through
the weekend and early next week until the ridge is pushed south over
the Gulf Coast by Tuesday afternoon.  This should bring temperatures
down a few more degrees by the end of the forecast period.
Unfortunately, rain chances do not increase substantially.  The
surface ridge axis is forecast to remain over the Deep South early
next week.  This has the effect of blocking moisture from The Gulf
from returning to the Mid Mississippi Valley.  While there is some
variance in model guidance, only about 15-20 percent of the LREF
members show any precipitation early next week, so unfortunately it
looks like there will be little if any relief from the very dry
conditions we`ve been experiencing for the foreseeable future.
Carney
&&
.AVIATION...  (For the 18z TAFs through 18z Wednesday Afternoon)
Issued at 1231 PM CDT Tue Sep 30 2025
VFR flight conditions and light winds are expected to continue to
prevail through the period.
Carney
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX

NWS LSX Office Area Forecast Discussion