March 2Ø12 Newsletter

The next SKYWARN meeting is 20-Mar @ 7:00 PM, the third Tuesday of the month.

Spotter Class
Steele County SKYWARN Spotter class is scheduled for 13-Mar. This class is for new spotters as well as a refresher for those previously trained. Remember, you must complete a Spotter Class at least every two years to remain certified.

If you can't make the 13-Mar class, look for other classes at Metro SKYWARN and NWS CHanhassen

Minnesota Skywarn Workshop
The 2012 Minnesota Skywarn Workshop has been set for April 14th at Schulze Hall at the University of St. Thomas. The keynote speaker will be Mr. Greg Carbin, the Warning Coordination Meteorologist at the Storm Prediction Center (SPC) in Norman, Oklahoma.

Spotter References The Spotter Reporting Checklist and Steele County Map with spotter "sweet spots" were updated for 2012. Download and print your own copy, or get a color copy at the next SKYWARN meeting. Be sure to put them in a protective sleeve.

March Moon Names From Multiple Sources
The full moon in March has several names: Racoon Moon, Sap Moon (sap starts flowing), Worm Moon (worm trails appear) Chaste moon, and Death moon.

Cloud Wheel
Need an idea to help educate others about cloud types? Make a cloud wheel. The cloud wheel consists of two disks that can be printed. After printing, the disks are cut into circles and assembled with a brass fastener.

The Weather Dashboard includes the NWS Forecast-At-A-Glance for Owatonna. Some of the information includes:

  • Expected weather for the next seven days.
  • Links to the latest weather hazards in your area.
  • Current weather conditions.
  • Links to weather history and other weather observation sites.
  • Doppler radar and satellite images.
The NWS provides a more detailed explanation of the information.

Tornado Outlooks From Several Sources
In the January Newsletter, we reported the Univesity of Colorado was delaying making huricane predictions. Columbia University, however, is now looking to make forecasts fot the tornado season. Heavy rain from thunderstorms and extreme wind shear are two weather factors most tied to active tornado months. The forecasts are targeted to be only one month in advance.

Satellite Rainfall Measurement From Multiple Sources
Hurricane Irene was a 10-day long event that dropped a lot of rain over a large area. NASA used microwave measurements from the Tropical Rainfall Measuring Mission (TRMM) satellite to accumulate the data. The satellite looks at microwave radiation from the earth. The resulting map shows over 8 inches of rain falling over North Carolina. Maps are also available for some extreme events dating back to 2003.

Atmospheric Rivers From Multiple Sources
Atmospheric Rivers (AR) are relatively narrow regions in the atmosphere that are responsible for most of the horizontal transport of water vapor outside of the tropics. Atmospheric rivers form due to temperature differences between the tropics and its poles. During winter, a strong temperature gradient develops across the hemisphere. The rivers can be over 1200 miles long and several hundred miles across. At any given time, somewhere between three and five atmospheric rivers are typically ferrying water in each hemisphere. Generally an issue along the west coast, it can produce large amount of rain and flooding. Up to 50% of the annual precipitation of some west coast states may come from ARs.

Ocean Color From Multiple Sources
Satellites can indicate the color of the ocean across the globe. SeaWiFS is one NASA project desinged to monitor the color of the ocean. Researchers use color to determine the concentration of microscopic marine plants, called phytoplankton. A high cencentration will tend to color the ocean green. This is one indication of a warm pool of water. The movement of the pool is one of many indicators used for predicting El Niņo and La Niņa events.

Storm Elves From Multiple Sources
Sprites are vertical electric discharges shaped that form at a height of between 31 and 53 miles. Elves are rings that expand and propagate themselves horizontally across the base of the ionosphere approximately 53 to 436 miles above earth. Bluish lightning bolts also exist that electrically connect the top of the clouds with the base of the ionosphere. A graphic shows the relationship between the three. Recording these discharges is difficult. Researchers were able to collect high speed images using a land based camera positioned over 250 miles from the storm. The European Space Agency plans to mount an instrument on the International Space Station in 2013 to learn more about them.

Sea Surface Temperatures From NASA Tech Briefs
Using data from the Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua spacecraft, Jet Propulsion Laboratory scientists found that every degree Centigrade increase in average sea surface temperature produced a 45 percent increase in the frequency of very high clouds - the type associated with severe storms and rainfall.

Term For the Month From Multiple Sources
Cobb Method
This is a method to forecast total snowfall amounts from a winter storm. The input data used in the algorithm includes storm duration, liquid water available to the storm, and changing snow ratio during the storm. It was developed in 2005 by Dan Cobb. One evaluation of the Cobb Method suggests it is has an accuracy rate of 77%.

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All Rights Reserved
Steele County SKYWARN
Owatonna, MN