Monthly outlook for Westerville, OH: average high 78.8°, average low 63°. That is 1.6° below the climate normal for August. Precipitation is expected on 8 days (about 5.4 inches), against a normal of 6 days and 1.7 inches. The warmest day looks like 9 August (88.2°), the coolest 23 August (52.4°).
78.8°/63°
Average high / low
−1.6°
Below normal
8 / 6
Wet days / normal
5.4 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
8 August – 17 August
79.8°
81.9°
-1.1°
18 August – 27 August
77.2°
81.6°
-2.5°
28 August – 6 September
at normal
80.3°
—
August records over 66 years
97°20 August 1983All-time high
45.5°29 August 1965All-time low
Climate normals and records are computed from the nearest reference point — Columbus (10 mi).
Sun, 0988° / 67°0
88 °
Westerville, Sunday, 9 August
Light rain. High 88°, low 67°.
Pressure30.06 inHg
Wind5.3 mph SW
Humidity64%
Visibility6.2 mi
Dew point68°
Mon, 1088° / 69°0.76
88 °
Westerville, Monday, 10 August
Heavy rain. High 88°, low 69°.
Pressure30.00 inHg
Wind13.6 mph SW
Humidity65%
Visibility6.2 mi
Dew point72°
Tue, 1181° / 67°3.27
81 °
Westerville, Tuesday, 11 August
Heavy rain. High 81°, low 67°.
Pressure29.97 inHg
Wind16.7 mph SW
Humidity89%
Visibility6.2 mi
Dew point69°
Wed, 1282° / 69°0.3
82 °
Westerville, Wednesday, 12 August
Rain. High 82°, low 69°.
Pressure29.80 inHg
Wind6.7 mph SW
Humidity90%
Visibility6.2 mi
Dew point73°
Thu, 1376° / 65°0.04
76 °
Westerville, Thursday, 13 August
Light rain. High 76°, low 65°.
Pressure29.91 inHg
Wind8 mph NE
Humidity76%
Visibility—
Dew point65°
Fri, 1472° / 58°0.01
72 °
Westerville, Friday, 14 August
Light rain. High 72°, low 58°.
Pressure30.09 inHg
Wind12.4 mph N
Humidity60%
Visibility—
Dew point56°
Sat, 1572° / 55°0
72 °
Westerville, Saturday, 15 August
Overcast. High 72°, low 55°.
Pressure30.30 inHg
Wind6.8 mph N
Humidity54%
Visibility—
Dew point52°
Sun, 1675° / 56°0
75 °
Westerville, Sunday, 16 August
Mostly clear. High 75°, low 56°.
Pressure30.27 inHg
Wind4.9 mph E
Humidity53%
Visibility—
Dew point54°
Mon, 1777° / 59°0.01
77 °
Westerville, Monday, 17 August
Light rain. High 77°, low 59°.
Pressure30.09 inHg
Wind5.7 mph SW
Humidity69%
Visibility—
Dew point59°
Tue, 1878° / 67°0.36
78 °
Westerville, Tuesday, 18 August
Rain. High 78°, low 67°.
Pressure29.97 inHg
Wind6.9 mph N
Humidity91%
Visibility—
Dew point69°
Wed, 1979° / 62°0
79 °
Westerville, Wednesday, 19 August
Mostly clear. High 79°, low 62°.
Pressure30.00 inHg
Wind4.9 mph E
Humidity54%
Visibility—
Dew point59°
Thu, 2081° / 65°0.38
81 °
Westerville, Thursday, 20 August
Rain. High 81°, low 65°.
Pressure29.88 inHg
Wind6.7 mph S
Humidity73%
Visibility—
Dew point67°
Fri, 2176° / 66°0.02
76 °
Westerville, Friday, 21 August
Light rain. High 76°, low 66°.
Pressure29.88 inHg
Wind11 mph N
Humidity71%
Visibility—
Dew point65°
Sat, 2279° / 62°0.08
79 °
Westerville, Saturday, 22 August
Light rain. High 79°, low 62°.
Pressure29.88 inHg
Wind11.1 mph N
Humidity57%
Visibility—
Dew point61°
Sun, 2369° / 52°0
69 °
Westerville, Sunday, 23 August
Clear. High 69°, low 52°.
Pressure30.15 inHg
Wind10.8 mph NE
Humidity54%
Visibility—
Dew point48°
From day 17 onward the outlook is built from 60-year climate statistics
Mon, 2481° / 63°0.05
81 °
Westerville, Monday, 24 August
Climate normal for this date — 60-year average.
Average high81°
Average low63°
Average precipitation0.05 in
Chance of precipitation25%
Record high94° (2007)
Record low52° (1971)
Tue, 2582° / 64°0.06
82 °
Westerville, Tuesday, 25 August
Climate normal for this date — 60-year average.
Average high82°
Average low64°
Average precipitation0.06 in
Chance of precipitation30%
Record high91° (2006)
Record low53° (1984)
Wed, 2682° / 64°0.11
82 °
Westerville, Wednesday, 26 August
Climate normal for this date — 60-year average.
Average high82°
Average low64°
Average precipitation0.11 in
Chance of precipitation32%
Record high92° (2024)
Record low53° (2017)
Thu, 2782° / 65°0.06
82 °
Westerville, Thursday, 27 August
Climate normal for this date — 60-year average.
Average high82°
Average low65°
Average precipitation0.06 in
Chance of precipitation28%
Record high93° (2024)
Record low53° (2025)
Fri, 2882° / 65°0.11
82 °
Westerville, Friday, 28 August
Climate normal for this date — 60-year average.
Average high82°
Average low65°
Average precipitation0.11 in
Chance of precipitation33%
Record high92° (2024)
Record low51° (1968)
Sat, 2981° / 64°0.16
81 °
Westerville, Saturday, 29 August
Climate normal for this date — 60-year average.
Average high81°
Average low64°
Average precipitation0.16 in
Chance of precipitation35%
Record high92° (1991)
Record low46° (1965)
Sun, 3081° / 64°0.16
81 °
Westerville, Sunday, 30 August
Climate normal for this date — 60-year average.
Average high81°
Average low64°
Average precipitation0.16 in
Chance of precipitation33%
Record high95° (2024)
Record low48° (1986)
Mon, 3180° / 63°0.09
80 °
Westerville, Monday, 31 August
Climate normal for this date — 60-year average.
Average high80°
Average low63°
Average precipitation0.09 in
Chance of precipitation33%
Record high93° (2012)
Record low51° (2009)
Tue, 0180° / 63°0.11
80 °
Westerville, Tuesday, 1 September
Climate normal for this date — 60-year average.
Average high80°
Average low63°
Average precipitation0.11 in
Chance of precipitation28%
Record high92° (2010)
Record low50° (1967)
Wed, 0281° / 63°0.08
81 °
Westerville, Wednesday, 2 September
Climate normal for this date — 60-year average.
Average high81°
Average low63°
Average precipitation0.08 in
Chance of precipitation32%
Record high93° (2011)
Record low49° (1967)
Thu, 0380° / 63°0.11
80 °
Westerville, Thursday, 3 September
Climate normal for this date — 60-year average.
Average high80°
Average low63°
Average precipitation0.11 in
Chance of precipitation28%
Record high94° (2011)
Record low50° (1967)
Fri, 0480° / 62°0.06
80 °
Westerville, Friday, 4 September
Climate normal for this date — 60-year average.
Average high80°
Average low62°
Average precipitation0.06 in
Chance of precipitation25%
Record high92° (2008)
Record low47° (1997)
Sat, 0579° / 61°0.08
79 °
Westerville, Saturday, 5 September
Climate normal for this date — 60-year average.
Average high79°
Average low61°
Average precipitation0.08 in
Chance of precipitation27%
Record high91° (2023)
Record low49° (1997)
Sun, 0679° / 61°0.03
79 °
Westerville, Sunday, 6 September
Climate normal for this date — 60-year average.
Average high79°
Average low61°
Average precipitation0.03 in
Chance of precipitation20%
Record high94° (2007)
Record low46° (1988)
About the monthly outlook
How accurate is a 30-day forecast?
The first 16 days come from weather models — reliable for the first 3–5 days and progressively less so after that. Days 17 through 30 for Westerville, OH are built from the climate normal, the 60-year average, so they show typical weather for those dates rather than a specific forecast.
What does "above normal" mean?
We compare the forecast against the climate normal for those exact calendar days, computed from 60 years of observations. The deviation shows how much the coming month differs from a typical one.
Where do the 66-year records come from?
They are real temperature extremes recorded in Westerville, OH since 1960: the highest and lowest reading for each calendar date, with the year it happened.
How often is it updated?
The forecast portion refreshes every hour; the climate portion is based on long-term data and stays stable.