As of 00:13 CDT

Weather in Symerton, IL

66°Current weather

Symerton, Sunday, 9 August, 00:13

Clear. Feels like 67°. High 89°, low 64°.

Pressure30.00 inHg
Wind0.8 mph SW
Humidity90%
Visibility6.2 mi
Dew point63°

Monthly outlook for Symerton, IL: average high 77.1°, average low 61.9°. That is 2° below the climate normal for August. Precipitation is expected on 4 days (about 0.5 inches), against a normal of 5 days and 1.7 inches. The warmest day looks like 9 August (89°), the coolest 21 August (52.4°).

77.1°/61.9°
Average high / low
−2°
Below normal
4 / 5
Wet days / normal
0.5 in
Precipitation this month

Ten-day blocks vs climate normal

PeriodForecast highNormalDifference
9 August – 18 August78.6°80.9°-1.2°
19 August – 28 August74.6°80.9°-3.5°
29 August – 7 Septemberat normal79.3°

August records over 66 years

97.9°24 August 2023All-time high
45.7°29 August 1986All-time low

Climate normals and records are computed from the nearest reference point — Joliet (14 mi).

Mon, 1087° / 72°0.11Rain
87 °Rain

Symerton, Monday, 10 August

Rain. High 87°, low 72°.

Pressure29.91 inHg
Wind12.3 mph SW
Humidity73%
Visibility6.2 mi
Dew point74°
Tue, 1185° / 73°0.11Light rain
85 °Light rain

Symerton, Tuesday, 11 August

Light rain. High 85°, low 73°.

Pressure29.80 inHg
Wind11.4 mph W
Humidity82%
Visibility6.2 mi
Dew point72°
Wed, 1282° / 68°0.01Light rain
82 °Light rain

Symerton, Wednesday, 12 August

Light rain. High 82°, low 68°.

Pressure29.85 inHg
Wind5.7 mph N
Humidity68%
Visibility6.2 mi
Dew point70°
Thu, 1373° / 62°0.03Light rain
73 °Light rain

Symerton, Thursday, 13 August

Light rain. High 73°, low 62°.

Pressure30.00 inHg
Wind8.6 mph SE
Humidity76%
Visibility
Dew point64°
Fri, 1477° / 60°0Mostly clear
77 °Mostly clear

Symerton, Friday, 14 August

Mostly clear. High 77°, low 60°.

Pressure30.09 inHg
Wind7.8 mph E
Humidity64%
Visibility
Dew point60°
Sat, 1565° / 58°0.01Light rain
65 °Light rain

Symerton, Saturday, 15 August

Light rain. High 65°, low 58°.

Pressure30.27 inHg
Wind7.4 mph S
Humidity83%
Visibility
Dew point56°
Sun, 1670° / 62°0Overcast
70 °Overcast

Symerton, Sunday, 16 August

Overcast. High 70°, low 62°.

Pressure30.15 inHg
Wind5.9 mph E
Humidity84%
Visibility
Dew point60°
Mon, 1778° / 62°0.01Light rain
78 °Light rain

Symerton, Monday, 17 August

Light rain. High 78°, low 62°.

Pressure30.06 inHg
Wind4.3 mph NW
Humidity71%
Visibility
Dew point63°
Tue, 1881° / 64°0Overcast
81 °Overcast

Symerton, Tuesday, 18 August

Overcast. High 81°, low 64°.

Pressure30.00 inHg
Wind8.9 mph SW
Humidity72%
Visibility
Dew point67°
Wed, 1973° / 59°0.06Light rain
73 °Light rain

Symerton, Wednesday, 19 August

Light rain. High 73°, low 59°.

Pressure29.91 inHg
Wind12.8 mph N
Humidity67%
Visibility
Dew point61°
Thu, 2068° / 53°0.02Light rain
68 °Light rain

Symerton, Thursday, 20 August

Light rain. High 68°, low 53°.

Pressure30.06 inHg
Wind10.3 mph N
Humidity66%
Visibility
Dew point54°
Fri, 2174° / 52°0Partly cloudy
74 °Partly cloudy

Symerton, Friday, 21 August

Partly cloudy. High 74°, low 52°.

Pressure30.09 inHg
Wind7.2 mph E
Humidity62%
Visibility
Dew point56°
Sat, 2273° / 55°0.01Light rain
73 °Light rain

Symerton, Saturday, 22 August

Light rain. High 73°, low 55°.

Pressure29.88 inHg
Wind13.2 mph S
Humidity77%
Visibility
Dew point61°
Sun, 2381° / 64°0Clear
81 °Clear

Symerton, Sunday, 23 August

Clear. High 81°, low 64°.

Pressure29.91 inHg
Wind13.7 mph W
Humidity60%
Visibility
Dew point64°
Mon, 2478° / 61°0.02Light rain
78 °Light rain

Symerton, Monday, 24 August

Light rain. High 78°, low 61°.

Pressure30.03 inHg
Wind4.7 mph S
Humidity70%
Visibility
Dew point65°
From day 17 onward the outlook is built from 60-year climate statistics
Tue, 2581° / 64°0.11Climate normal
81 °Climate normal

Symerton, Tuesday, 25 August

Climate normal for this date — 60-year average.

Average high81°
Average low64°
Average precipitation0.11 in
Chance of precipitation27%
Record high92° (1991)
Record low52° (2017)
Wed, 2682° / 66°0.17Climate normal
82 °Climate normal

Symerton, Wednesday, 26 August

Climate normal for this date — 60-year average.

Average high82°
Average low66°
Average precipitation0.17 in
Chance of precipitation35%
Record high95° (2024)
Record low51° (1964)
Thu, 2782° / 66°0.12Climate normal
82 °Climate normal

Symerton, Thursday, 27 August

Climate normal for this date — 60-year average.

Average high82°
Average low66°
Average precipitation0.12 in
Chance of precipitation27%
Record high96° (2024)
Record low53° (2025)
Fri, 2881° / 65°0.11Climate normal
81 °Climate normal

Symerton, Friday, 28 August

Climate normal for this date — 60-year average.

Average high81°
Average low65°
Average precipitation0.11 in
Chance of precipitation25%
Record high93° (1984)
Record low48° (1986)
Sat, 2981° / 64°0.12Climate normal
81 °Climate normal

Symerton, Saturday, 29 August

Climate normal for this date — 60-year average.

Average high81°
Average low64°
Average precipitation0.12 in
Chance of precipitation33%
Record high94° (1984)
Record low46° (1986)
Sun, 3080° / 64°0.07Climate normal
80 °Climate normal

Symerton, Sunday, 30 August

Climate normal for this date — 60-year average.

Average high80°
Average low64°
Average precipitation0.07 in
Chance of precipitation22%
Record high93° (2013)
Record low50° (1986)
Mon, 3180° / 63°0.07Climate normal
80 °Climate normal

Symerton, Monday, 31 August

Climate normal for this date — 60-year average.

Average high80°
Average low63°
Average precipitation0.07 in
Chance of precipitation22%
Record high90° (2011)
Record low51° (2009)
Tue, 0180° / 63°0.11Climate normal
80 °Climate normal

Symerton, Tuesday, 1 September

Climate normal for this date — 60-year average.

Average high80°
Average low63°
Average precipitation0.11 in
Chance of precipitation30%
Record high96° (2011)
Record low49° (2009)
Wed, 0280° / 63°0.06Climate normal
80 °Climate normal

Symerton, Wednesday, 2 September

Climate normal for this date — 60-year average.

Average high80°
Average low63°
Average precipitation0.06 in
Chance of precipitation22%
Record high94° (2008)
Record low47° (2017)
Thu, 0380° / 63°0.08Climate normal
80 °Climate normal

Symerton, Thursday, 3 September

Climate normal for this date — 60-year average.

Average high80°
Average low63°
Average precipitation0.08 in
Chance of precipitation25%
Record high93° (2023)
Record low49° (1974)
Fri, 0478° / 62°0.1Climate normal
78 °Climate normal

Symerton, Friday, 4 September

Climate normal for this date — 60-year average.

Average high78°
Average low62°
Average precipitation0.1 in
Chance of precipitation28%
Record high92° (2023)
Record low47° (1974)
Sat, 0579° / 62°0.06Climate normal
79 °Climate normal

Symerton, Saturday, 5 September

Climate normal for this date — 60-year average.

Average high79°
Average low62°
Average precipitation0.06 in
Chance of precipitation17%
Record high90° (1983)
Record low50° (1974)
Sun, 0678° / 62°0.12Climate normal
78 °Climate normal

Symerton, Sunday, 6 September

Climate normal for this date — 60-year average.

Average high78°
Average low62°
Average precipitation0.12 in
Chance of precipitation37%
Record high92° (1990)
Record low48° (1988)
Mon, 0778° / 61°0.13Climate normal
78 °Climate normal

Symerton, Monday, 7 September

Climate normal for this date — 60-year average.

Average high78°
Average low61°
Average precipitation0.13 in
Chance of precipitation35%
Record high93° (1960)
Record low47° (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 Symerton, 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 Symerton, 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.