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

Updated: 4:00 am EDT Aug 17, 2026

Monday Slight Chance Showers And T-Storms then Showers And T-Storms Likely Tuesday Mostly Sunny Wednesday Partly Sunny then Chance Showers And T-Storms Thursday Chance Showers And T-Storms Friday Mostly Sunny Saturday Mostly Sunny then Slight Chance Showers And T-Storms Sunday Slight Chance Rain Showers then Slight Chance Showers And T-Storms   Hi 80 °F Hi 79 °F Hi 79 °F Hi 77 °F Hi 77 °F Hi 78 °F Hi 77 °F   Overnight Mostly Cloudy Monday Night Chance Showers And T-Storms then Partly Cloudy Tuesday Night Partly Cloudy Wednesday Night Chance Showers And T-Storms Thursday Night Chance Showers And T-Storms then Partly Cloudy Friday Night Partly Cloudy Saturday Night Slight Chance Showers And T-Storms   Lo 70 °F Lo 62 °F Lo 61 °F Lo 63 °F Lo 59 °F Lo 58 °F Lo 60 °F

Forecast from NOAA-NWS for Lancaster, OH.

166
FXUS61 KILN 170652
AFDILN

Area Forecast Discussion
National Weather Service Wilmington OH
252 AM EDT Mon Aug 17 2026

.WHAT HAS CHANGED...
No significant changes.

&&

.KEY MESSAGES...
1) A few more rounds of showers and thunderstorms will occur ahead
of a cold front that will move through the region this afternoon.

2) Another cold front will move through Wednesday night bringing
below normal temperatures for the end of the week.

&&

.DISCUSSION...
KEY MESSAGE 1)
MCS moving out of southern Illinois into southern Indiana will
continue east through the early morning hours into the forecast
area, although it should weaken as it moves into an area with less
instability.

Cold front extending from northeast Indiana into southeast Missouri
will move across the region this afternoon. Additional showers and
thunderstorms will develop along and ahead of the boundary. The
deeper plume of precipitable water will be decreasing and shunting
off to the southeast, although values will still be quite high. And
deep warm cloud depths will remain in place, so locally heavy rain
will still be possible. Environment looks pretty marginal for any
severe, although cannot rule out a few stronger storms.

KEY MESSAGE 2)
Dew points will drop back into the 60s in the wake of Monday`s cold
front, and temperatures will fall to or a bit below normal. Moisture
will increase once again on Wednesday ahead of an approaching cold
front, although not to the degree that has been the case for much of
the past week. The front will sag through the area Wednesday night
into Thursday morning as minor impulses of energy move through the
base of a long wave trough that is slowly shift eastward. Showers and
possibly some storms could linger in southern counties into Thursday
night when a more energetic short wave move southeast into the
Tennessee Valley giving the front a stronger push south. After this
front passes, even cooler conditions will prevail through the end of
the week with highs in the mid 70s to around 80 and lows in the mid
50s to lower 60s.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
Area of showers and storms moving into western Indiana will continue
eastwards, likely weakening over time, but still impacting the
terminals, especially in the Cincinnati area, after 09Z. In the wake
of this, expect MVFR ceilings to develop. Ahead of this, IFR ceilings
may develop at KCMH/KLCK. Additional showers and storms will occur as
a cold front moves across the terminals through 22Z. In addition to a
wind shift, expect ceilings to lift to VFR and then scatter after
00Z.

OUTLOOK...No significant weather expected.

&&

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

&&

$$

DISCUSSION...35
AVIATION...35

NWS ILN Office Area Forecast Discussion