August 212 Newsletter

The next SKYWARN meeting is 21-Aug @ 7:00 PM, the third Tuesday of the month.

Steele County Free Fair
The SCFF begins on 14-Aug and runs through 19-Aug. If severe weather develops, visitors and participants may be told to seek shelter. It could take a long time to get everyone to a safe location. Steele county SKYWARN is being asked to help provide as much advance notice as possible. We will respond by deploying sooner and over a larger area. Please give extra consideration to responding to during SCFF week becasue of the number of people that will be outdoors.

What Cloud is That?
Several people sent Dave KCUVY photos like this one from 17-Jun. It is like a waffle - almost straight lines of "ridges" with evenly spaced and similarly sized "holes" or thin spots. These were mid-level clouds located in the rain free base following the storms that went through Sunday afternoon.

Autmn resceived a response from the NWS out of Springfield, MO:

Undulatus asperatus (or alternately, asperatus) is a rare, newly recognized cloud formation, that was proposed in 2009 as the first cloud formation added since cirrus intortus in 1951 to the International Cloud Atlas of the World Meteorological Organization. The name translates approximately as roughened or agitated waves.

The clouds are most closely related to undulatus clouds. Although they appear dark and storm-like, they tend to dissipate without a storm forming. The ominous-looking clouds have been particularly common in the Plains states of the United States, often during the morning or midday hours following convective thunderstorm activity. As of June 2009[update] the Royal Meteorological Society is gathering evidence of the type of weather patterns in which undulatus asperatus clouds appear, so as to study how they form and decide whether they are distinct from other undulatus clouds.

See the NWS Springfield,MO web site for information on a similar siting on 07-Jun-2008 there.

August Sturgeon moon From Multiple Sources
Sturgeons are a large fish of the Great Lakes and other major bodies of water. Fishing tribes provide the source of the name because the sturgeons are readily caught during this month. During this month, the full moon will look its roundest. The Perseid meteor shower also occurs during this full moon and may not be as visible due to the brightness of the full moon.

Pollution From Multiple Sources
Thunderstorm clouds form from a convective cycle. Warm air rises in updrafts while cooler air falls. Water vapor condenses at the higher altitudes and form water droplets. When components of air pollution are involved, the particulates keep the water molecules small. The smaller water droplets are carried to higher altitudes by the updrafts, rather than letting gravity take hold of them. One result may be less rain falling from the clouds. Larger anvils may develop, trapping heat in the lower atmosphere.

Term For The Month From Multiple Sources
This term is the Canadian equivalent to our National Weather Service Heat Index. The main difference between the two systems is the Humidex is based on dew point while the US Heat Index is based on Relative Humidity. Both systems provide a dry temperature equivalent approximating what temperature an individual "feels" it is. Of course, the US is in Farenheit and the Canadian system is Celsius.

Copyright 2012
All Rights Reserved
Steele County SKYWARN
Owatonna, MN