Forecast Details for Johnston City, IL

Recent Locations: Herlong, CA Coal City, IN Johnston City, IL

Overnight: Partly cloudy, with a low around 58. Calm wind.

Wednesday: Sunny, with a high near 88. Calm wind becoming west southwest 5 to 8 mph in the afternoon.

Wednesday Night: A 50 percent chance of showers and thunderstorms. Increasing clouds, with a low around 61. Light and variable wind becoming west northwest around 6 mph after midnight.

Thursday: A slight chance of thunderstorms before 7am. Mostly cloudy, then gradually becoming sunny, with a high near 78. North northwest wind around 7 mph. Chance of precipitation is 10%.

Thursday Night: Mostly clear, with a low around 58. Calm wind becoming south around 5 mph after midnight.

Friday: A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 86. South southwest wind 6 to 10 mph becoming west northwest in the afternoon.

Friday Night: A chance of showers and thunderstorms. Mostly cloudy, with a low around 55. North wind 3 to 8 mph. Chance of precipitation is 50%.

Saturday: A slight chance of showers before 1pm. Mostly sunny, with a high near 79. North northwest wind 3 to 7 mph.

Saturday Night: Mostly clear, with a low around 53. North wind around 5 mph becoming calm in the evening.

Sunday: Sunny, with a high near 80. Calm wind becoming east northeast 5 to 7 mph in the morning.

Sunday Night: Partly cloudy, with a low around 55. Light east wind.

Monday: Mostly sunny, with a high near 80. East wind 3 to 7 mph.

Monday Night: Partly cloudy, with a low around 59. East wind around 5 mph becoming calm in the evening.

Tuesday: A slight chance of showers. Partly sunny, with a high near 81. Light and variable wind becoming south 5 to 7 mph in the morning.

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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

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North America Water Vapor (Moisture)

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Weather Topic: What are Contrails?

Home - Education - Cloud Types - Contrails

Next Topic: Cumulonimbus Clouds

A contrail is an artificial cloud, created by the passing of an aircraft.

Contrails form because water vapor in the exhaust of aircraft engines is suspended in the air under certain temperatures and humidity conditions. These contrails are called exhaust contrails.

Another type of contrail can form due to a temporary reduction in air pressure moving over the plane's surface, causing condensation. These are called aerodynamic contrails.

When you can see your breath on a cold day, it is also because of condensation. The reason contrails last longer than the condensation from your breath is because the water in contrails freezes into ice particles.

Next Topic: Cumulonimbus Clouds

Weather Topic: What are Cumulus Clouds?

Home - Education - Cloud Types - Cumulus Clouds

Next Topic: Drizzle

Cumulus clouds are fluffy and textured with rounded tops, and may have flat bottoms. The border of a cumulus cloud is clearly defined, and can have the appearance of cotton or cauliflower.

Cumulus clouds form at low altitudes (rarely above 2 km) but can grow very tall, becoming cumulus congestus and possibly the even taller cumulonimbus clouds. When cumulus clouds become taller, they have a greater chance of producing precipitation.

Next Topic: Drizzle