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As of 00:14 CDT

Weather in Alton, IL

77°Current weather

Alton, Sunday, 9 August, 00:14

Clear. Feels like 78°. High 96°, low 73°.

Pressure30.03 inHg
Wind5.9 mph SE
Humidity87%
Visibility6.2 mi
Dew point72°

Two-week outlook for Alton, IL: week one averages a high of 88.8° and week two 80.5°, so week two runs 8.3° cooler than week one. Around 2.9 inches of precipitation are expected over the 14 days, across 9 wet days. The nearest weekend, August 9: 96°, dry.

Week one vs week two

WeekHighLowPrecipitationVs normal
1st (August 9 – August 15)88.8°71.6°2.5 in / 6 d—
2nd (August 16 – August 22)80.5°64.5°0.4 in / 3 d—

Weekend weather

Sun, August 9
Overcast
96°73°
no precip.
Sat, August 15
Light rain
77°68°
0.22 in
Sun, August 16
Light rain
79°66°
0.09 in
Sat, August 22
Light rain
85°63°
0.19 in
Mon, 10100° / 77°0.05Light rain
100 °Light rain

Alton, Monday, 10 August

Light rain. High 100°, low 77°.

Pressure29.94 inHg
Wind10.8 mph SW
Humidity46%
Visibility6.2 mi
Dew point70°
Tue, 11102° / 74°0.06Light rain
102 °Light rain

Alton, Tuesday, 11 August

Light rain. High 102°, low 74°.

Pressure29.85 inHg
Wind10.6 mph SW
Humidity47%
Visibility6.2 mi
Dew point70°
Wed, 1288° / 74°0.09Light rain
88 °Light rain

Alton, Wednesday, 12 August

Light rain. High 88°, low 74°.

Pressure29.85 inHg
Wind4.6 mph NW
Humidity65%
Visibility6.2 mi
Dew point70°
Thu, 1384° / 68°1.51Heavy rain
84 °Heavy rain

Alton, Thursday, 13 August

Heavy rain. High 84°, low 68°.

Pressure29.91 inHg
Wind13.6 mph E
Humidity68%
Visibility—
Dew point70°
Fri, 1475° / 68°0.56Rain
75 °Rain

Alton, Friday, 14 August

Rain. High 75°, low 68°.

Pressure30.06 inHg
Wind10.2 mph E
Humidity86%
Visibility—
Dew point69°
Sat, 1577° / 68°0.22Light rain
77 °Light rain

Alton, Saturday, 15 August

Light rain. High 77°, low 68°.

Pressure30.18 inHg
Wind13.3 mph SE
Humidity81%
Visibility—
Dew point66°
Sun, 1679° / 66°0.09Light rain
79 °Light rain

Alton, Sunday, 16 August

Light rain. High 79°, low 66°.

Pressure30.06 inHg
Wind10.5 mph E
Humidity81%
Visibility—
Dew point70°
Mon, 1782° / 68°0.11Light rain
82 °Light rain

Alton, Monday, 17 August

Light rain. High 82°, low 68°.

Pressure30.03 inHg
Wind6.4 mph NE
Humidity79%
Visibility—
Dew point70°
Tue, 1882° / 69°0.04Light rain
82 °Light rain

Alton, Tuesday, 18 August

Light rain. High 82°, low 69°.

Pressure30.00 inHg
Wind8.9 mph SW
Humidity80%
Visibility—
Dew point72°
Wed, 1985° / 70°0Overcast
85 °Overcast

Alton, Wednesday, 19 August

Overcast. High 85°, low 70°.

Pressure29.91 inHg
Wind12.3 mph NE
Humidity61%
Visibility—
Dew point68°
Thu, 2075° / 59°0Partly cloudy
75 °Partly cloudy

Alton, Thursday, 20 August

Partly cloudy. High 75°, low 59°.

Pressure30.03 inHg
Wind12.2 mph NE
Humidity58%
Visibility—
Dew point56°
Fri, 2175° / 57°0.02Light rain
75 °Light rain

Alton, Friday, 21 August

Light rain. High 75°, low 57°.

Pressure30.03 inHg
Wind12.1 mph E
Humidity57%
Visibility—
Dew point55°
Sat, 2285° / 63°0.19Light rain
85 °Light rain

Alton, Saturday, 22 August

Light rain. High 85°, low 63°.

Pressure29.83 inHg
Wind12.7 mph SE
Humidity59%
Visibility—
Dew point65°

About this forecast

Can I plan a trip on a 2-week forecast?

Week one is solid for planning — accuracy is high. Week two shows the trend: go by the averages and the comparison with normal, and check the details closer to the date.

What does the "Vs normal" column mean?

It is the gap between the forecast and the climate normal for those same dates in Alton, IL, computed over 60 years. A positive value means the week runs warmer than usual.

Why are weekends shown separately?

Saturday and Sunday plans are what people check most, so we give them their own cards with temperature and precipitation.