Forecast Details for Alton, IL

Recent Locations: Forest Park, GA Alton, IL

Today: Sunny, with a high near 72. West wind 14 to 18 mph, with gusts as high as 28 mph.

Tonight: Partly cloudy, with a low around 51. Northwest wind 6 to 11 mph, with gusts as high as 20 mph.

Thursday: Mostly sunny, with a high near 66. Northwest wind 9 to 14 mph, with gusts as high as 22 mph.

Thursday Night: Mostly clear, with a low around 48. Northwest wind 5 to 10 mph becoming light in the evening.

Friday: Mostly sunny, with a high near 71. Northwest wind 3 to 6 mph.

Friday Night: A 30 percent chance of showers. Mostly cloudy, with a low around 53.

Saturday: Showers likely. Mostly cloudy, with a high near 66. Chance of precipitation is 70%.

Saturday Night: Showers and possibly a thunderstorm. Some of the storms could produce heavy rainfall. Low around 57. Chance of precipitation is 90%.

Sunday: Showers and possibly a thunderstorm. High near 68. Chance of precipitation is 80%.

Sunday Night: Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 54. Chance of precipitation is 60%.

Memorial Day: A 50 percent chance of showers and thunderstorms. Partly sunny, with a high near 66.

Monday Night: A 20 percent chance of showers. Partly cloudy, with a low around 52.

Tuesday: A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 71.

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Current U.S. National Radar--Current

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National Weather Forecast--Current

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National Weather Forecast for Tomorrow

Tomorrow National Weather Forecast and Tomorrow National Weather Map are show below.

North America Water Vapor (Moisture)

This map shows recent moisture content over North America. Bright and colored areas show high moisture (ie, clouds); brown indicates very little moisture present; black indicates no moisture.

Weather Topic: What are Stratus Clouds?

Home - Education - Cloud Types - Stratus Clouds

Next Topic: Wall Clouds

Stratus clouds are similar to altostratus clouds, but form at a lower altitude and are identified by their fog-like appearance, lacking the distinguishing features of most clouds.

Stratus clouds are wider than most clouds, and their base has a smooth, uniform look which is lighter in color than a nimbostratus cloud. The presence of a stratus cloud indicates the possibility of minor precipitation, such as drizzle, but heavier precipitation does not typically arrive in the form of a stratus cloud.

Next Topic: Wall Clouds

Weather Topic: What are Altocumulus Clouds?

Home - Education - Cloud Types - Altocumulus Clouds

Next Topic: Altostratus Clouds

Similar to cirrocumulus clouds, altocumulus clouds are characterized by cloud patches. They are distinguished by larger cloudlets than cirrocumulus clouds but are still smaller than stratocumulus clouds.

Altocumulus clouds most commonly form in middle altitudes (between 2 and 5 km) and may resemble, at times, the shape of a flying saucer. These uncommon formations, called altocumulus lenticularis, are created by uplift in the atmosphere and are most often seen in close proximity to mountains.

Next Topic: Altostratus Clouds