Monthly outlook for Prairietown, IL: average high 92.9°, average low 72.2°. That is 4.2° above the climate normal for August. Precipitation is expected on 4 days (about 0.9 inches), against a normal of 5 days and 1.6 inches. The warmest day looks like 20 August (110.2°), the coolest 14 August (64.7°).
92.9°/72.2°
Average high / low
+4.2°
Above normal
4 / 5
Wet days / normal
0.9 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
9 August – 18 August
88.1°
85.4°
+1.5°
19 August – 28 August
100.9°
85.6°
+8.5°
29 August – 7 September
at normal
83.3°
—
August records over 66 years
102.9°15 August 2007All-time high
51.8°29 August 1986All-time low
Climate normals and records are computed from the nearest reference point — Edwardsville (12 mi).
Mon, 10101° / 75°0.01
101 °
Prairietown, Monday, 10 August
Light rain. High 101°, low 75°.
Pressure29.94 inHg
Wind9.8 mph SW
Humidity54%
Visibility6.2 mi
Dew point72°
Tue, 1198° / 73°0
98 °
Prairietown, Tuesday, 11 August
Light rain. High 98°, low 73°.
Pressure29.88 inHg
Wind12 mph SW
Humidity56%
Visibility6.2 mi
Dew point73°
Wed, 1290° / 73°0.16
90 °
Prairietown, Wednesday, 12 August
Rain. High 90°, low 73°.
Pressure29.83 inHg
Wind7.1 mph NW
Humidity65%
Visibility6.2 mi
Dew point73°
Thu, 1383° / 69°0.4
83 °
Prairietown, Thursday, 13 August
Light rain. High 83°, low 69°.
Pressure29.91 inHg
Wind13.1 mph E
Humidity70%
Visibility—
Dew point70°
Fri, 1473° / 65°0.19
73 °
Prairietown, Friday, 14 August
Light rain. High 73°, low 65°.
Pressure30.06 inHg
Wind15.9 mph E
Humidity86%
Visibility—
Dew point65°
Sat, 1583° / 65°0.1
83 °
Prairietown, Saturday, 15 August
Light rain. High 83°, low 65°.
Pressure30.12 inHg
Wind13.2 mph SE
Humidity79%
Visibility—
Dew point69°
Sun, 1686° / 69°0
86 °
Prairietown, Sunday, 16 August
Overcast. High 86°, low 69°.
Pressure30.03 inHg
Wind9.9 mph E
Humidity73%
Visibility—
Dew point73°
Mon, 1784° / 70°0
84 °
Prairietown, Monday, 17 August
Partly cloudy. High 84°, low 70°.
Pressure30.06 inHg
Wind7.5 mph E
Humidity68%
Visibility—
Dew point69°
Tue, 1887° / 66°0
87 °
Prairietown, Tuesday, 18 August
Overcast. High 87°, low 66°.
Pressure29.97 inHg
Wind11.3 mph SE
Humidity66%
Visibility—
Dew point69°
Wed, 19100° / 75°0
100 °
Prairietown, Wednesday, 19 August
Partly cloudy. High 100°, low 75°.
Pressure29.88 inHg
Wind12.1 mph S
Humidity48%
Visibility—
Dew point70°
Thu, 20110° / 78°0
110 °
Prairietown, Thursday, 20 August
Partly cloudy. High 110°, low 78°.
Pressure29.83 inHg
Wind12 mph SW
Humidity34%
Visibility—
Dew point67°
Fri, 2196° / 77°0
96 °
Prairietown, Friday, 21 August
Clear. High 96°, low 77°.
Pressure29.85 inHg
Wind9.6 mph E
Humidity52%
Visibility—
Dew point71°
Sat, 22101° / 77°0
101 °
Prairietown, Saturday, 22 August
Clear. High 101°, low 77°.
Pressure29.85 inHg
Wind10.2 mph S
Humidity34%
Visibility—
Dew point64°
Sun, 23105° / 77°0.02
105 °
Prairietown, Sunday, 23 August
Light rain. High 105°, low 77°.
Pressure29.85 inHg
Wind10.4 mph SW
Humidity42%
Visibility—
Dew point67°
Mon, 2494° / 74°0.03
94 °
Prairietown, Monday, 24 August
Light rain. High 94°, low 74°.
Pressure30.00 inHg
Wind8.9 mph E
Humidity58%
Visibility—
Dew point71°
From day 17 onward the outlook is built from 60-year climate statistics
Tue, 2586° / 69°0.06
86 °
Prairietown, Tuesday, 25 August
Climate normal for this date — 60-year average.
Average high86°
Average low69°
Average precipitation0.06 in
Chance of precipitation23%
Record high98° (2023)
Record low58° (1966)
Wed, 2686° / 69°0.11
86 °
Prairietown, Wednesday, 26 August
Climate normal for this date — 60-year average.
Average high86°
Average low69°
Average precipitation0.11 in
Chance of precipitation32%
Record high97° (1983)
Record low54° (2025)
Thu, 2786° / 69°0.14
86 °
Prairietown, Thursday, 27 August
Climate normal for this date — 60-year average.
Average high86°
Average low69°
Average precipitation0.14 in
Chance of precipitation30%
Record high97° (1983)
Record low56° (2025)
Fri, 2886° / 69°0.09
86 °
Prairietown, Friday, 28 August
Climate normal for this date — 60-year average.
Average high86°
Average low69°
Average precipitation0.09 in
Chance of precipitation28%
Record high97° (1990)
Record low55° (1986)
Sat, 2985° / 68°0.07
85 °
Prairietown, Saturday, 29 August
Climate normal for this date — 60-year average.
Average high85°
Average low68°
Average precipitation0.07 in
Chance of precipitation28%
Record high97° (1984)
Record low52° (1986)
Sun, 3084° / 68°0.12
84 °
Prairietown, Sunday, 30 August
Climate normal for this date — 60-year average.
Average high84°
Average low68°
Average precipitation0.12 in
Chance of precipitation27%
Record high97° (2013)
Record low52° (1986)
Mon, 3184° / 68°0.11
84 °
Prairietown, Monday, 31 August
Climate normal for this date — 60-year average.
Average high84°
Average low68°
Average precipitation0.11 in
Chance of precipitation32%
Record high101° (2013)
Record low56° (1967)
Tue, 0184° / 68°0.12
84 °
Prairietown, Tuesday, 1 September
Climate normal for this date — 60-year average.
Average high84°
Average low68°
Average precipitation0.12 in
Chance of precipitation32%
Record high99° (2011)
Record low53° (1967)
Wed, 0283° / 67°0.1
83 °
Prairietown, Wednesday, 2 September
Climate normal for this date — 60-year average.
Average high83°
Average low67°
Average precipitation0.1 in
Chance of precipitation33%
Record high98° (2011)
Record low53° (1974)
Thu, 0383° / 67°0.09
83 °
Prairietown, Thursday, 3 September
Climate normal for this date — 60-year average.
Average high83°
Average low67°
Average precipitation0.09 in
Chance of precipitation28%
Record high95° (2011)
Record low51° (1974)
Fri, 0482° / 66°0.12
82 °
Prairietown, Friday, 4 September
Climate normal for this date — 60-year average.
Average high82°
Average low66°
Average precipitation0.12 in
Chance of precipitation30%
Record high96° (1960)
Record low53° (1974)
Sat, 0583° / 66°0.04
83 °
Prairietown, Saturday, 5 September
Climate normal for this date — 60-year average.
Average high83°
Average low66°
Average precipitation0.04 in
Chance of precipitation13%
Record high97° (1998)
Record low53° (1974)
Sun, 0683° / 66°0.05
83 °
Prairietown, Sunday, 6 September
Climate normal for this date — 60-year average.
Average high83°
Average low66°
Average precipitation0.05 in
Chance of precipitation20%
Record high97° (1990)
Record low54° (1988)
Mon, 0783° / 65°0.08
83 °
Prairietown, Monday, 7 September
Climate normal for this date — 60-year average.
Average high83°
Average low65°
Average precipitation0.08 in
Chance of precipitation25%
Record high96° (1960)
Record low51° (2025)
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 Prairietown, 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 Prairietown, 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.