Monthly outlook for Olympia Fields, IL: average high 78.9°, average low 64°. That is 0.6° below the climate normal for August. Precipitation is expected on 4 days (about 0.5 inches), against a normal of 6 days and 1.9 inches. The warmest day looks like 9 August (87.7°), the coolest 21 August (55.7°).
78.9°/64°
Average high / low
−0.6°
Below normal
4 / 6
Wet days / normal
0.5 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
8 August – 17 August
80.1°
80.1°
+0°
18 August – 27 August
76.8°
80°
-1.8°
28 August – 6 September
at normal
78.6°
—
August records over 66 years
97°24 August 2023All-time high
46.8°29 August 1965All-time low
Climate normals and records are computed from the nearest reference point — Orland Hills (9 mi).
Sun, 0988° / 64°0.07
88 °
Olympia Fields, Sunday, 9 August
Rain. High 88°, low 64°.
Pressure29.97 inHg
Wind13.1 mph S
Humidity72%
Visibility6.2 mi
Dew point73°
Mon, 1087° / 72°0.23
87 °
Olympia Fields, Monday, 10 August
Rain. High 87°, low 72°.
Pressure29.91 inHg
Wind7.3 mph SW
Humidity66%
Visibility6.2 mi
Dew point73°
Tue, 1181° / 73°0.12
81 °
Olympia Fields, Tuesday, 11 August
Rain. High 81°, low 73°.
Pressure29.80 inHg
Wind11.9 mph SW
Humidity82%
Visibility6.2 mi
Dew point72°
Wed, 1284° / 68°0.01
84 °
Olympia Fields, Wednesday, 12 August
Light rain. High 84°, low 68°.
Pressure29.85 inHg
Wind4.8 mph N
Humidity55%
Visibility6.2 mi
Dew point66°
Thu, 1376° / 64°0
76 °
Olympia Fields, Thursday, 13 August
Overcast. High 76°, low 64°.
Pressure30.00 inHg
Wind6.9 mph E
Humidity53%
Visibility—
Dew point56°
Fri, 1479° / 61°0
79 °
Olympia Fields, Friday, 14 August
Clear. High 79°, low 61°.
Pressure30.09 inHg
Wind9.1 mph NE
Humidity41%
Visibility—
Dew point51°
Sat, 1567° / 62°0.01
67 °
Olympia Fields, Saturday, 15 August
Light rain. High 67°, low 62°.
Pressure30.27 inHg
Wind5.4 mph SE
Humidity65%
Visibility—
Dew point54°
Sun, 1675° / 64°0
75 °
Olympia Fields, Sunday, 16 August
Overcast. High 75°, low 64°.
Pressure30.15 inHg
Wind5.1 mph S
Humidity64%
Visibility—
Dew point58°
Mon, 1780° / 64°0
80 °
Olympia Fields, Monday, 17 August
Overcast. High 80°, low 64°.
Pressure30.06 inHg
Wind7.2 mph W
Humidity61%
Visibility—
Dew point62°
Tue, 1883° / 66°0
83 °
Olympia Fields, Tuesday, 18 August
Overcast. High 83°, low 66°.
Pressure29.97 inHg
Wind9.7 mph SW
Humidity62%
Visibility—
Dew point65°
Wed, 1977° / 66°0.05
77 °
Olympia Fields, Wednesday, 19 August
Light rain. High 77°, low 66°.
Pressure29.91 inHg
Wind11.7 mph NW
Humidity52%
Visibility—
Dew point57°
Thu, 2069° / 57°0.01
69 °
Olympia Fields, Thursday, 20 August
Light rain. High 69°, low 57°.
Pressure30.06 inHg
Wind10 mph N
Humidity59%
Visibility—
Dew point53°
Fri, 2176° / 56°0
76 °
Olympia Fields, Friday, 21 August
Mostly clear. High 76°, low 56°.
Pressure30.06 inHg
Wind6.8 mph NE
Humidity45%
Visibility—
Dew point51°
Sat, 2273° / 57°0.01
73 °
Olympia Fields, Saturday, 22 August
Light rain. High 73°, low 57°.
Pressure29.88 inHg
Wind10 mph SE
Humidity72%
Visibility—
Dew point58°
Sun, 2383° / 65°0
83 °
Olympia Fields, Sunday, 23 August
Clear. High 83°, low 65°.
Pressure29.91 inHg
Wind13.8 mph W
Humidity48%
Visibility—
Dew point59°
From day 17 onward the outlook is built from 60-year climate statistics
Mon, 2480° / 65°0.13
80 °
Olympia Fields, Monday, 24 August
Climate normal for this date — 60-year average.
Average high80°
Average low65°
Average precipitation0.13 in
Chance of precipitation27%
Record high97° (2023)
Record low55° (1965)
Tue, 2580° / 65°0.09
80 °
Olympia Fields, Tuesday, 25 August
Climate normal for this date — 60-year average.
Average high80°
Average low65°
Average precipitation0.09 in
Chance of precipitation28%
Record high91° (2003)
Record low51° (2017)
Wed, 2681° / 66°0.15
81 °
Olympia Fields, Wednesday, 26 August
Climate normal for this date — 60-year average.
Average high81°
Average low66°
Average precipitation0.15 in
Chance of precipitation40%
Record high93° (2024)
Record low53° (1964)
Thu, 2781° / 66°0.12
81 °
Olympia Fields, Thursday, 27 August
Climate normal for this date — 60-year average.
Average high81°
Average low66°
Average precipitation0.12 in
Chance of precipitation33%
Record high95° (2024)
Record low54° (2025)
Fri, 2880° / 65°0.15
80 °
Olympia Fields, Friday, 28 August
Climate normal for this date — 60-year average.
Average high80°
Average low65°
Average precipitation0.15 in
Chance of precipitation35%
Record high92° (1984)
Record low50° (1986)
Sat, 2980° / 65°0.13
80 °
Olympia Fields, Saturday, 29 August
Climate normal for this date — 60-year average.
Average high80°
Average low65°
Average precipitation0.13 in
Chance of precipitation37%
Record high93° (1984)
Record low47° (1965)
Sun, 3079° / 64°0.09
79 °
Olympia Fields, Sunday, 30 August
Climate normal for this date — 60-year average.
Average high79°
Average low64°
Average precipitation0.09 in
Chance of precipitation32%
Record high92° (2013)
Record low51° (1986)
Mon, 3179° / 64°0.06
79 °
Olympia Fields, Monday, 31 August
Climate normal for this date — 60-year average.
Average high79°
Average low64°
Average precipitation0.06 in
Chance of precipitation23%
Record high89° (2012)
Record low53° (2023)
Tue, 0179° / 63°0.13
79 °
Olympia Fields, Tuesday, 1 September
Climate normal for this date — 60-year average.
Average high79°
Average low63°
Average precipitation0.13 in
Chance of precipitation30%
Record high95° (2011)
Record low51° (2009)
Wed, 0279° / 64°0.07
79 °
Olympia Fields, Wednesday, 2 September
Climate normal for this date — 60-year average.
Average high79°
Average low64°
Average precipitation0.07 in
Chance of precipitation27%
Record high92° (2008)
Record low49° (2017)
Thu, 0379° / 64°0.07
79 °
Olympia Fields, Thursday, 3 September
Climate normal for this date — 60-year average.
Average high79°
Average low64°
Average precipitation0.07 in
Chance of precipitation28%
Record high92° (2023)
Record low51° (1974)
Fri, 0477° / 63°0.09
77 °
Olympia Fields, Friday, 4 September
Climate normal for this date — 60-year average.
Average high77°
Average low63°
Average precipitation0.09 in
Chance of precipitation32%
Record high90° (2023)
Record low50° (2025)
Sat, 0578° / 62°0.07
78 °
Olympia Fields, Saturday, 5 September
Climate normal for this date — 60-year average.
Average high78°
Average low62°
Average precipitation0.07 in
Chance of precipitation23%
Record high89° (2023)
Record low51° (1974)
Sun, 0677° / 62°0.11
77 °
Olympia Fields, Sunday, 6 September
Climate normal for this date — 60-year average.
Average high77°
Average low62°
Average precipitation0.11 in
Chance of precipitation42%
Record high91° (1990)
Record low49° (1962)
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 Olympia Fields, IL 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 Olympia Fields, IL 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.