Saturday, April 23, 2011


Global climate change, an intensifier,  has many a local consequence as we on the prairie know very well.  Our weather is in Cinerama grand wraparound dimensions and when one drives eighty miles to the grocery store or movies, one and all pay close attention.  Check the computer (the web cams are especially helpful if you’re crossing the Rockies, which we often do), check the paper, and check the neighbors.  When you fill up your gas tank, ask travelers which way they came.
Last week I attended a class in Skywarn Spotting, officially sponsored by the National Weather Service and a new organization called “The Community Collaborative Rain, Hail and Snow Network.”  For short, “CoCoRaHS”.  I really think they ought to have a mascot rooster.  The teacher was a young woman who had us raising our hands in response to various questions.  The answers were always obvious, but she encouraged us by recognizing our “awesome” success.   The only failure was that most of us found the specialized weather radios pretty lame.  Broadcasts are low power and most of the cell phones around here are of the “can you hear me now?” variety.  Some people were at the class for formal credit from agencies.
The first two pieces of summer-focused advice were probably the most crucial.  One was that if the weather was building into a storm and you were out on the land, you should have a buddy with you to watch your back.  The other was that a highway overpass is one of the deadliest places to seek refuge.  High winds are easily able to lift them out of place and crash them back down heedlessly.  Maybe you already know not to get under a tree.  You might be marginally drier, but you may also become electrified.   
Some of the advice was self-contradictory.  If there is a tornado aimed at you, get down flat or in a ditch.  If the storm is dumping large amounts of water, don’t get in the ditch if it might suddenly carry the water your way.  And if you feel your hair stirring with electricity, do NOT lie flat but rather curl into a ball with your hands over your head and don’t put your toes down on the ground -- just the rest of your foot.  The idea is to let the electricity pass on out of you and it may follow your toes out !!  Bottom line?  Go indoors.
The idea of the class is to fortify the National Weather Service’ radar and the automated weather stations around the state (there’s one in the Valier library) with personal observations.  Report in a formula:  “This is X.  I am a trained weather watcher.  I am (x miles N/S/E/W of X or a GPS figure).  I am reporting a (name phenomena and be specific: size of hail, estimated wind speed) which is traveling N/S/E/W.”  The report is to go to the phone number on a laminated card we each received, no matter where we are, even out of state, since the Weather Service is a network and will share all information.
Weather is the result of the sun's power being stirred by the rotation and tipping of the planet which act through four dimensions:  moisture, instability, lift, and windsheer.  These are what produce the enormous disturbances that pound our crops and explode our houses, as well as making the land sizzle with electricity -- much of lightning goes UP from the ground.
Now we turned our attention to the hierarchy of storms.  The single cell storm is a piled up cumulus full of moisture, reacting to warm land and cold altitude, which means warm air going up and cold air falling down:  that’s windsheer and the molecules rubbing together produce electricity.  When multiple cells form a line, which is not unlikely, they are called a “squall line.”  (Not too long ago an indignant Native American woman who didn’t listen very carefully wanted to know why storms were called “squaw lines.”  Short answer: NOT.)   
Then comes the crucial element:  rotation.  If the rotation creates the familiar Dorothy-in-Kansas upright whirl, that’s bad.  Check your options for taking cover.  If the spiral is hanging down from the cumulus storm cloud but not touching the ground, it’s a funnel cloud.  if it’s connected only to the ground and not any overhead cloud, it’s a “gustnado” which can do damage but is separated from its power source.  If both ends are connected, one to the ground and one to the cloud, then it’s a true tornado.  All three should be reported immediately as you take cover.  You cannot outrun a tornado.
But it’s possible for clouds to rotate by rolling from top to bottom which creates a “shelf cloud” that pulls storms along horizontally and may create “downbursts” large or small.  At the side of them can be curls of air like the toes of a harem shoe.  This will make a “dustnado” and indeed is officially called a “foot.”
If the cloud is releasing moisture, it may be rain which sometimes looks like long dark fringe.  If it is creating a “hail shaft” that will be a white, milky sort of line.  If the moisture is falling but then evaporating before it touches the ground, it is called “virga.”  ALWAYS report hail.  When you report rain and snow, try to get a measurement of how much moisture there is.  This brought up a good Montana weather question:  how do you measure horizontal precipitation?  The answer was to take readings in various places and average them, but it wasn’t a good answer since a five foot drift is often next to dry ground.  Sometimes there IS no good answer, because humans are following something far beyond ourselves, trying to name and describe it for our own uses.
Don’t report lightning because there is ALWAYS lightning.  It doesn’t relate to severity of weather and can leap out of the inside of a storm that is thirty miles away.  Do not stand at the window as it can strike you through the glass.  How I love to watch a storm through a big window!
Never drive through water standing on the road.  I did that once and came close to drowning.  I was driving a van, which converted itself into a boat and because the motor was high enough and the current was weak enough, the wheels paddled me to safety.  Only barely.  Water was bubbling up through the floor and the van wanted to turn turtle. 
Report dense fog even if it is patchy.
The most dangerous condition we know is a “fire whirl.”  A park service employee had seen one and testified to the TRULY awesome sight of it over his shoulder as he fled.  This is the sort of phenomenon through which Shiva and the Old Testament Jehovah speak.  The biggest lesson the sky has to teach us is respect for mighty forces which we can only barely predict and report.

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