Forecast Details for Merna, IL

Recent Locations: Augusta, ME Carthage, AR Merna, IL

Current Alerts for Merna, IL: Wind Advisory

Tonight: Showers and possibly a thunderstorm. Low around 42. East southeast wind around 17 mph, with gusts as high as 25 mph. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

Thursday: Showers and thunderstorms likely before 1pm, then showers likely and possibly a thunderstorm between 1pm and 5pm, then a chance of showers and thunderstorms after 5pm. Cloudy, with a high near 73. Windy, with a south wind 18 to 23 mph increasing to 27 to 32 mph in the afternoon. Winds could gust as high as 44 mph. Chance of precipitation is 70%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

Thursday Night: Showers and possibly a thunderstorm before 1am, then a slight chance of showers and thunderstorms between 1am and 4am, then a slight chance of showers after 4am. Low around 56. Breezy, with a south southwest wind 23 to 28 mph decreasing to 13 to 18 mph after midnight. Winds could gust as high as 39 mph. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

Friday: A 50 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 77. South wind 8 to 16 mph, with gusts as high as 22 mph.

Friday Night: Showers and possibly a thunderstorm. Low around 54. South wind 14 to 17 mph, with gusts as high as 23 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.

Saturday: Showers likely, mainly before 1pm. Mostly cloudy, with a high near 62. Breezy, with a west wind 15 to 21 mph, with gusts as high as 29 mph. Chance of precipitation is 60%. New precipitation amounts between a quarter and half of an inch possible.

Saturday Night: Mostly cloudy, with a low around 34. Breezy, with a west wind 18 to 22 mph, with gusts as high as 26 mph.

Sunday: Mostly sunny, with a high near 52. Breezy.

Sunday Night: Mostly clear, with a low around 34.

Monday: Sunny, with a high near 58.

Monday Night: Partly cloudy, with a low around 33.

Tuesday: Mostly sunny, with a high near 52.

Tuesday Night: Partly cloudy, with a low around 32.

Wednesday: Partly sunny, with a high near 63.

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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