National Weather Service Forecast for: Lancaster, OH Issued by: National Weather Service Wilmington, OH

Updated: 4:00 am EDT Sep 19, 2026

Saturday Partly Sunny then Slight Chance Showers And T-Storms Sunday Rain Showers Likely then Chance Showers And T-Storms Monday Chance Rain Showers Tuesday Chance Rain Showers Wednesday Showers And T-Storms Likely Thursday Chance Rain Showers Friday Mostly Sunny   Hi 82 °F Hi 82 °F Hi 70 °F Hi 69 °F Hi 68 °F Hi 69 °F Hi 70 °F   Overnight Mostly Cloudy Saturday Night Slight Chance Showers And T-Storms then Showers And T-Storms Likely Sunday Night Chance Showers And T-Storms then Showers And T-Storms Likely Monday Night Chance Rain Showers Tuesday Night Showers And T-Storms Likely Wednesday Night Showers And T-Storms Likely Thursday Night Slight Chance Rain Showers then Mostly Cloudy   Lo 59 °F Lo 66 °F Lo 57 °F Lo 54 °F Lo 56 °F Lo 54 °F Lo 52 °F

Forecast from NOAA-NWS for Lancaster, OH.

826
FXUS61 KILN 190658
AFDILN

Area Forecast Discussion
National Weather Service Wilmington OH
258 AM EDT Sat Sep 19 2026

.WHAT HAS CHANGED...
Fog potential early this morning greatly reduced due to lingering
clouds.

&&

.KEY MESSAGES...
1) Showers and thunderstorms will be possible this afternoon and
evening. Some storms could have strong to damaging winds.

2) Additional rounds of showers and thunderstorms will occur through
Sunday night with a potential for heavy rain.

3) Cooler and showery weather will occur for the first half of the
week.

&&

.DISCUSSION...
KEY MESSAGE 1)
While the primary active zone of convection will be across the lower
Great Lakes today, there will be a weak disturbance south of there
that will move across the region during peak heating. The atmosphere
will become moderately unstable, but bulk shear will be on the
weaker side. However, DCAPE will be around 1000 J/kg. So if storms
become robust, then they will have the potential for strong
downdrafts that could lead to strong to damaging wind gusts. At this
stage the greatest potential appears to be across southeast Indiana,
southwest Ohio, and northern Kentucky. Precipitable water will be
increasing to around 1.8 inches, so storms could produce locally
heavy rainfall, but they should be progressive enough to keep any
hydrologic concerns at a minimum.

KEY MESSAGE 2)
Active zonal flow will remain across the region through the rest of
the weekend. Each wave of convection will be a little further south
than the previous one. So for tonight, expect primary activity to be
across northern Indiana and northern Ohio, but the southern flank of
this activity may move across northern counties. Parameters will be
favorable for efficient warm rain processes, and northern counties
still have the most vulnerable ground conditions due to previous
heavy rainfall. It appears that activity will be progressive with a
limited potential for repeated rounds of rainfall, as may occur just
a bit further north. But this will have to be monitored closely in
case there are any southward adjustments to the more active
convective corridor.

Weak low pressure and a cold front will move across the forecast
area Sunday afternoon and evening. Another round of showers and
some thunderstorms will occur along and north of the front. There
will still be a heavy rain threat with precipitable water near 1.8
inches and warm cloud depth around 4 km. Greatest potential will be
any enhancement in precipitation intensity near the low pressure
system.

KEY MESSAGE 3)
In the wake of the front, a cooler airmass will prevail over the
area. A rather dynamic short wave moving out the Plains will close
off in the Mississippi Valley and then slowly work its way east
across the region through mid week. This will result in periods of
showers and maybe some embedded thunderstorms.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
Some lower clouds are lingering across the area, especially near the
Cincinnati terminals. There may be some temporary MVFR ceilings early
on. If clouds decrease as forecast, there there will be a narrow
window before daybreak when fog may develop at KLUK and also at KILN.

Beyond this, VFR will prevail outside of any thunderstorms with
scattered to broken cumulus. There is a chance that showers and
thunderstorms could cross the region between 18Z and 0Z with a
slight better chance in the Cincinnati area. Lower clouds should
clear out towards 0Z with lingering mid to high clouds late in the
period.

OUTLOOK...Thunderstorms possible again Sunday afternoon and evening.
MVFR to IFR ceilings and visibilities possible Sunday night through
Tuesday.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...None.
KY...None.
IN...None.

&&

$$

DISCUSSION...35
AVIATION...35

NWS ILN Office Area Forecast Discussion