Monthly outlook for Gartside, IL: average high 87.3°, average low 69.1°. That is 0.5° above the climate normal for August. Precipitation is expected on 6 days (about 1.7 inches), against a normal of 5 days and 1.7 inches. The warmest day looks like 11 August (101.2°), the coolest 15 August (56.1°).
87.3°/69.1°
Average high / low
+0.5°
Above normal
6 / 5
Wet days / normal
1.7 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
8 August – 17 August
89°
86.4°
+1.5°
18 August – 27 August
84.3°
86.5°
-1.2°
28 August – 6 September
at normal
84.4°
—
August records over 66 years
103.5°15 August 2007All-time high
49.8°29 August 1986All-time low
Climate normals and records are computed from the nearest reference point — St. Louis (13 mi).
Sun, 0995° / 73°0
95 °
Gartside, Sunday, 9 August
Partly cloudy. High 95°, low 73°.
Pressure29.97 inHg
Wind12.2 mph S
Humidity57%
Visibility6.2 mi
Dew point72°
Mon, 1099° / 74°0
99 °
Gartside, Monday, 10 August
Clear. High 99°, low 74°.
Pressure29.94 inHg
Wind12.1 mph SW
Humidity45%
Visibility6.2 mi
Dew point70°
Tue, 11101° / 75°0.03
101 °
Gartside, Tuesday, 11 August
Light rain. High 101°, low 75°.
Pressure29.88 inHg
Wind7.8 mph W
Humidity41%
Visibility6.2 mi
Dew point68°
Wed, 1287° / 75°0.07
87 °
Gartside, Wednesday, 12 August
Light rain. High 87°, low 75°.
Pressure29.85 inHg
Wind14.6 mph W
Humidity47%
Visibility6.2 mi
Dew point69°
Thu, 1385° / 71°0.44
85 °
Gartside, Thursday, 13 August
Rain. High 85°, low 71°.
Pressure29.85 inHg
Wind11 mph SE
Humidity65%
Visibility—
Dew point70°
Fri, 1477° / 64°0.03
77 °
Gartside, Friday, 14 August
Light rain. High 77°, low 64°.
Pressure30.15 inHg
Wind11.2 mph NE
Humidity50%
Visibility—
Dew point55°
Sat, 1579° / 56°0
79 °
Gartside, Saturday, 15 August
Overcast. High 79°, low 56°.
Pressure30.27 inHg
Wind8.5 mph E
Humidity45%
Visibility—
Dew point51°
Sun, 1680° / 61°0.07
80 °
Gartside, Sunday, 16 August
Light rain. High 80°, low 61°.
Pressure30.18 inHg
Wind13 mph S
Humidity66%
Visibility—
Dew point62°
Mon, 1797° / 72°0.31
97 °
Gartside, Monday, 17 August
Rain. High 97°, low 72°.
Pressure29.91 inHg
Wind17.2 mph S
Humidity49%
Visibility—
Dew point68°
Tue, 1888° / 74°0
88 °
Gartside, Tuesday, 18 August
Overcast. High 88°, low 74°.
Pressure29.97 inHg
Wind10.1 mph NE
Humidity59%
Visibility—
Dew point69°
Wed, 1995° / 71°0
95 °
Gartside, Wednesday, 19 August
Partly cloudy. High 95°, low 71°.
Pressure29.91 inHg
Wind7 mph SE
Humidity55%
Visibility—
Dew point69°
Thu, 2086° / 73°0.64
86 °
Gartside, Thursday, 20 August
Heavy rain. High 86°, low 73°.
Pressure29.88 inHg
Wind7.6 mph S
Humidity63%
Visibility—
Dew point70°
Fri, 2181° / 70°0.06
81 °
Gartside, Friday, 21 August
Light rain. High 81°, low 70°.
Pressure29.91 inHg
Wind9.5 mph NE
Humidity72%
Visibility—
Dew point69°
Sat, 2284° / 66°0
84 °
Gartside, Saturday, 22 August
Overcast. High 84°, low 66°.
Pressure29.94 inHg
Wind5.9 mph NE
Humidity47%
Visibility—
Dew point59°
Sun, 2372° / 61°0.02
72 °
Gartside, Sunday, 23 August
Light rain. High 72°, low 61°.
Pressure30.12 inHg
Wind12.6 mph NE
Humidity60%
Visibility—
Dew point56°
From day 17 onward the outlook is built from 60-year climate statistics
Mon, 2486° / 68°0.09
86 °
Gartside, Monday, 24 August
Climate normal for this date — 60-year average.
Average high86°
Average low68°
Average precipitation0.09 in
Chance of precipitation30%
Record high100° (2023)
Record low57° (2015)
Tue, 2587° / 69°0.06
87 °
Gartside, Tuesday, 25 August
Climate normal for this date — 60-year average.
Average high87°
Average low69°
Average precipitation0.06 in
Chance of precipitation25%
Record high100° (2023)
Record low56° (2015)
Wed, 2687° / 69°0.13
87 °
Gartside, Wednesday, 26 August
Climate normal for this date — 60-year average.
Average high87°
Average low69°
Average precipitation0.13 in
Chance of precipitation32%
Record high99° (1983)
Record low58° (2015)
Thu, 2787° / 69°0.12
87 °
Gartside, Thursday, 27 August
Climate normal for this date — 60-year average.
Average high87°
Average low69°
Average precipitation0.12 in
Chance of precipitation28%
Record high98° (1983)
Record low56° (2015)
Fri, 2887° / 69°0.08
87 °
Gartside, Friday, 28 August
Climate normal for this date — 60-year average.
Average high87°
Average low69°
Average precipitation0.08 in
Chance of precipitation27%
Record high98° (1990)
Record low55° (1967)
Sat, 2985° / 68°0.07
85 °
Gartside, Saturday, 29 August
Climate normal for this date — 60-year average.
Average high85°
Average low68°
Average precipitation0.07 in
Chance of precipitation27%
Record high98° (1984)
Record low50° (1986)
Sun, 3085° / 68°0.11
85 °
Gartside, Sunday, 30 August
Climate normal for this date — 60-year average.
Average high85°
Average low68°
Average precipitation0.11 in
Chance of precipitation28%
Record high98° (2013)
Record low53° (1986)
Mon, 3185° / 68°0.11
85 °
Gartside, Monday, 31 August
Climate normal for this date — 60-year average.
Average high85°
Average low68°
Average precipitation0.11 in
Chance of precipitation32%
Record high102° (2013)
Record low56° (1967)
Tue, 0184° / 68°0.11
84 °
Gartside, Tuesday, 1 September
Climate normal for this date — 60-year average.
Average high84°
Average low68°
Average precipitation0.11 in
Chance of precipitation33%
Record high99° (2011)
Record low52° (1967)
Wed, 0284° / 67°0.12
84 °
Gartside, Wednesday, 2 September
Climate normal for this date — 60-year average.
Average high84°
Average low67°
Average precipitation0.12 in
Chance of precipitation33%
Record high98° (2011)
Record low54° (1974)
Thu, 0384° / 67°0.1
84 °
Gartside, Thursday, 3 September
Climate normal for this date — 60-year average.
Average high84°
Average low67°
Average precipitation0.1 in
Chance of precipitation27%
Record high97° (2011)
Record low51° (1974)
Fri, 0483° / 66°0.13
83 °
Gartside, Friday, 4 September
Climate normal for this date — 60-year average.
Average high83°
Average low66°
Average precipitation0.13 in
Chance of precipitation27%
Record high98° (1960)
Record low52° (1974)
Sat, 0583° / 66°0.05
83 °
Gartside, Saturday, 5 September
Climate normal for this date — 60-year average.
Average high83°
Average low66°
Average precipitation0.05 in
Chance of precipitation15%
Record high97° (1998)
Record low51° (1974)
Sun, 0683° / 65°0.05
83 °
Gartside, Sunday, 6 September
Climate normal for this date — 60-year average.
Average high83°
Average low65°
Average precipitation0.05 in
Chance of precipitation22%
Record high98° (1990)
Record low52° (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 Gartside, 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 Gartside, 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.