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

Updated: 2:29 am EDT Aug 16, 2026

Sunday Showers And T-Storms Likely Monday Slight Chance Showers And T-Storms then Chance Showers And T-Storms Tuesday Sunny Wednesday Partly Sunny then Chance Showers And T-Storms Thursday Chance Rain Showers then Mostly Sunny Friday Slight Chance Rain Showers Saturday Mostly Sunny then Slight Chance Showers And T-Storms   Hi 85 °F Hi 81 °F Hi 79 °F Hi 80 °F Hi 75 °F Hi 76 °F Hi 78 °F   Overnight Showers And T-Storms Likely Sunday Night Chance Showers And T-Storms then Mostly Cloudy Monday Night Mostly Clear Tuesday Night Mostly Clear Wednesday Night Chance Showers And T-Storms Thursday Night Partly Cloudy Friday Night Partly Cloudy   Lo 71 °F Lo 70 °F Lo 61 °F Lo 62 °F Lo 62 °F Lo 57 °F Lo 58 °F

Flood Watch
 

Forecast from NOAA-NWS for Lancaster, OH.

709
FXUS61 KILN 160741
AFDILN

Area Forecast Discussion
National Weather Service Wilmington OH
341 AM EDT Sun Aug 16 2026

.WHAT HAS CHANGED...
No significant changes.

&&

.KEY MESSAGES...
1) More showers and thunderstorms will occur today. Locally heavy
rainfall and some strong to severe storms will be possible.

2) A cold front will slowly move through the region tonight into
Monday with another cold front moving through Wednesday and
Wednesday night.

&&

.DISCUSSION...
KEY MESSAGE 1)
A cluster of thunderstorms that has developed on the nose of a
modest low level jet will move through the middle of the forecast
area through the early morning hours. This activity has been pretty
cellular and progressive, so the flood threat looks to be low but non
zero. Thus will let the flood watch continue until expiration. At
this point, do not expect to extend it, even though additional
convection is likely during the day.

It appears that another impulse will cause more thunderstorms develop
and move across the area this afternoon. This will also be
associated with a pre-frontal trough. Precipitable water will still
be high, but the warm cloud layer will not be quite as deep. So there
may still be locally heavy rain, but the flooding threat appears to
be more isolated. In addition, with moderate instability there could
be some more robust storms that could produce strong to damaging
winds.


KEY MESSAGE 2)
Low amplitude short wave will push a cold front into the area
tonight. This will become elongated in a north northeast to south
southwest orientation which will cause the boundary to be slow to
move all of the way through the region. There will still be some
potential for showers and storms until this front clears.

Broad long wave trough will move into the Great Lakes towards mid
week. This will push another cold front through late Wednesday into
Wednesday night. There will be a bigger change in air mass with highs
will be in the 70s with lows in the 50s to lower 60s for the latter
part of the week.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
Small cluster of thunderstorms will move from KDAY to KCMH/KLCK
during the early part of the period. Another larger area of
thunderstorms is forecast to pass across the entire area between 16Z
and 22Z. In between these two events, there is some chance that MVFR
ceilings may develop at KCMH/KLCK, although confidence is medium at
best. Otherwise, VFR will prevail outside of thunderstorms. Winds
will become westerly during the day with some gusts to around 20 kt.

OUTLOOK..MVFR ceilings possible late tonight into Monday morning.
Thunderstorms possible Monday.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...Flood Watch until 8 AM EDT this morning for OHZ026-034-035-042>046-
     051>056-060>065-070>074-080>082-088.
KY...None.
IN...Flood Watch until 8 AM EDT this morning for INZ050-058-059-066.

&&

$$

DISCUSSION...35
AVIATION...35

NWS ILN Office Area Forecast Discussion