Monthly Archives: March 2016

Why are there different types of precipitation?

When particles fall from clouds and reach the surface as precipitation, they do so primarily as rain, snow, freezing rain or sleet.

The main difference between these different types of precipitation is the temperature variations between the cloud base and the ground. Last week, Madison experienced all four of these precipitation types. Continue reading

Category: Meteorology, Seasons

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What forced last week’s strong winds?

Our windy Wednesday last week was a notable departure from a winter without many high-wind events.

The strong winds from Tuesday and Wednesday were a result of the passage of an intensifying low-pressure center (mid-latitude cyclone) nearly directly over Madison overnight Tuesday into Wednesday. Continue reading

Category: Meteorology, Severe Weather

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Did we have a normal winter this year?

As far as our winter time mean temperature, southern Wisconsin was above normal by about 5 degrees.

Being warmer than normal is typical during an El Nino year, and that is what we experienced this winter. Continue reading

Category: Climate, Meteorology, Seasons

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How severe has this winter been?

It may not surprise anyone that the average temperature from Dec. 1 to Feb. 29 this season in Madison was 5.67 degrees above normal, with most of that surplus accumulated during an extremely warm December that was 12 degrees above average.

There are other ways to assess the winter severity that are less local in nature. Four times each day we calculate the areal extent of air colder than minus 5 degrees Celsius at 1 mile above the surface using weather data supplied by the National Center for Environmental Prediction. Averaging the four measurements per day together creates a daily value of the areal extent of this “cold pool.” Continue reading

Category: Meteorology, Seasons

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