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WeatherLive › Illinois › Alton

Alton, IL Weather

Today Hourly 10-Day Weekend Monthly Radar Air Quality Climate
Current WeatherAlton · 12:17 AM CDT
77° | 53°
74°F
Feels like 72°
Rain
WindN 19 mph · Gusts 22 mph
Precip90% · 1.46 in
Humidity91% · Dew point 72°
UV index9 Very high
Air Quality26 Good
Pressure30.33 inHg
Visibility6 mi
Sunrise / Sunset6:16 AM · 7:53 PM · 13h 37m

Weather map — Alton

Full radar →
Now
77°
26%
20 mph
01:00
74°
0.24 in
19 mph
02:00
74°
0.24 in
21 mph
03:00
74°
0.24 in
23 mph
04:00
73°
0.24 in
24 mph
05:00
73°
0.24 in
25 mph
06:00
73°
0.24 in
22 mph
07:00
53°
25%
22 mph
08:00
53°
26%
22 mph
09:00
53°
25%
23 mph
10:00
53°
25%
25 mph
11:00
53°
21%
24 mph
12:00
54°
25%
25 mph
13:00
54°
26%
26 mph
14:00
54°
26%
25 mph
15:00
54°
26%
25 mph
16:00
54°
26%
27 mph
17:00
54°
26%
27 mph
18:00
54°
27%
27 mph
19:00
54°
27%
26 mph
20:00
54°
27%
26 mph
21:00
54°
28%
27 mph
22:00
54°
27%
27 mph
23:00
54°
28%
28 mph

Today · Mon 8/17

High 77°
90% / 1.46 in

Mostly cloudy. Winds NW at 28 mph.

Overnight · Mon 8/17

Low 53°
85% / 0.24 in

Rain. Winds N at 19 mph.

Tomorrow · Tue 8/18

55° | 54°
87% / 0.17 in

Mostly cloudy. Winds NW at 30 mph.

7-day trend

Alton · temperature + precipitation

10-day forecast

Updated 12:17 AM

Details & indices

Wind
19 mph N
Gusts 22 mph
Humidity
91%
Dew point 72°
Pressure
30.33 inHg
Rising
UV index
9 — Very high
High today
Air Quality
Good
AQI 26 · US EPA
Allergy
Low
Mugwort
Visibility
6 mi
Clear view
Allergy — Alton

🌿 Conditions right now

View all →
Birch
None
Grass
Low
Oak
None
Alder
None
Hazel
None
Mugwort
Low
Ragweed
Low

Sun & moon

Sunrise6:16 AM
Sunset7:53 PM
Length of day13h 37m
Moonrise11:40 AM
Moonset10:13 PM
Moon phase🌒 Waxing Crescent · 23%
Next full moonAug 27 Sturgeon Moon
Latitude38.8906°N
Longitude-90.1843°E

Water temps nearby

View all →
No beaches within 50 miles
🌤️No rain expected in the next 90 minutes
Now+30+60+90 min
Minute-by-minute precip · HRRR nowcast

Daily planner

computed from today's forecast
Laundry day
Poor
Line-drying weather
Grilling
Poor
Fire up the grill
Running
Poor
Lace up outside
Patio
Poor
Dinner outdoors
Nearby places in {{REGION}}
🌤️
Chicago
—
— 🌤️
Aurora
—
— 🌤️
Rockford
—
— 🌤️
Joliet
—
— 🌤️
Naperville
—
—
Data sources · Monday, August 17
Where the Alton forecast comes from
This page blends NOAA/NWS model guidance with global ensembles for the 10-day outlook, air quality and alerts. Data refreshes every hour, current conditions every 15 minutes. Coordinates: 38.8906°N, -90.1843°.
NBM + global weather models
Updated: 12:17 AM
Weather in Alton
The 10-day span for Alton runs from a high near 77° on Monday down to 47° overnight on Tuesday. About 3.4 in of precipitation is expected in total; the most likely wet day is Monday (90% chance). Wind is the one to watch: gusts to 47 mph around Friday. No watches or warnings are active for the area right now. Right now Alton is about 10° cooler than nearby St. Louis. Longer view: variable mid-latitude weather in every season.
Alton, IL · Elev 492 ft · 38.89°N, 90.18°W · Illinois · Forecast computed for these exact coordinates
Powered by NWS/NOAA guidance, multi-model forecasts and official environmental feeds · NOAA/NWS · EPA AirNow · MET Norway · global models
Updated: 12:17 AM