Stewart Knowitall is the Herald Review’s go-to guy for answers on any subject. With his vast network of educated professionals, Stewart will help answer the questions confounding the minds of our younger readers. Look for the answers he finds to questions from third graders across Osceola County once each month. If you have a question for Stewart Knowitall, email askus@pioneergroup.com.

Kiali Stout asks: Why do storms come and go?

Hi Kiali, Stewart Knowitall here. I found Jeff Andresen, a really smart professor at Michigan State University.

Here’s his answer to your question.

Dear Kiali,

This is a very good question. The answer depends somewhat on where you live and on what type of storm you are interested in.

There are some things all storms have in common. Almost all meteorological events we call 'storms' require energy, and/or a shifting and changing of the way energy is displayed in the weather.

In a very simple way of thinking about it, storms happen when there is imbalance of energy somewhere in the earth’s climate system and are simply a part of the way nature reduces or eliminates that imbalance. (Like when you sneeze if you have a cold.)

The number of storms, how strong they are, and how often they come and go depend on where and when these energy imbalances occur.

The most common storm we have in the area where you live is a thunderstorm.

Thunderstorms

Unlike hurricanes, thunderstorms usually affect much smaller areas, sometimes only a few square miles - like Reed City or Evart.

Thunderstorms, in general, are a result of temporary and localized instability which leads to air moving upwards, condensation which often makes clouds, and precipitation (usually rain.)

The primary energy source is relatively warm and humid air and at low levels of the atmosphere and occasionally winds at higher levels.

Most thunderstorms pass and disappear within relatively short times (less than 30 minutes) as the storm loses the source of its updraft (and energy).

In Michigan, the number of thunderstorms each yearis usually less than 30 in far northern sections of the state to more than 40 along the Indiana and Ohio border. They are most common during the summer months, with the average annual peak occurring in July.

Storms which create a lot of wind for long periods of time - a few hours - are called ‘supercell’ thunderstorms and can produce tornadoes as well as large hail and damaging winds.

While really bad thunderstorms and violent weather events do happen on a regular basis in Michigan, they are not as common as in states further south and west.

Tornados happen in Michigan on average of about five per year, with about 90 percent of confirmed tornadoes occurring in the southern half of the Lower Peninsula.

I hope this is of help.

Regards,

Jeff Andresen

Dr. Jeffrey A. Andresen is associate professor of meteorology/climatology with Michigan State University’s Department of Geography, Extension Specialist with Michigan State University Extension, and the State Climatologist for Michigan. He holds a B.S. degree from Northern Illinois University in meteorology and M.S. and Ph.D. degrees from Purdue University in agricultural meteorology/climatology. Dr. Andresen has professional experience with the National Weather Service and with the USDA’s World Agricultural Outlook Board in Washington, D.C., where he was involved in international crop/weather impact assessment and production estimation. The primary focus of Andresen’s research has been the influence of weather and climate on agriculture, both in the USA and in international production areas.

Dr. Andresen is the author or co-author of over 100 peer-reviewed publications, outreach-related papers, and other scholarly works.