A WEATHER FEATURE CALLED “SOG”

satsfc.gif JULY 21, 2013

Map #1 Now you see it

satsfc.gif July 23, 2013

Map #2 Now you don’t

(click maps to enlarge)

A WEATHER FEATURE CALLED “SOG”

Sometimes I correctly forecast the weather even though nothing on the map behaves in a way I would call “correct.”  The map misbehaves, and I have the urge to scold it.  Then I become confused, for I’m not sure what I saw, or intuitively knew, or “was feeling in my bones,” for I can’t see it as a nicely outlined feature on the map.

What map #1 above shows is a massive, warm Bermuda High bulging west all  the way to Texas. Map #2 shows it simply melting away to a remnant in the Gulf of Mexico, replaced in the northeast by an impressive trough of low pressure.  In essence features have shifted thousands of miles without fronts moving much, and without winds.

In my bones I knew that big, hot air mass wouldn’t simply disappear without a whimper.  I expected it to punch the puny polar front right in the snoot and to come surging back north.  However the map shows that front still to our south.

However yesterday, when I stepped outside, I could see that on some level my stone-aged forecasting techniques were right, because the muggy air had come right back, as if that massive high still existed.  And today we are having torrential, tropical downpours, as I would expect on the west side of a big, juicy Bermuda High.

I assume the front was penciled in south of us on the above maps without the map-maker asking anyone in New England if the air was still cool and polar.  It isn’t.  We got a mere taste of Canada on Saturday evening and Sunday morning, before Georgia came surging back.  Even when the slight winds shifted to the east, and the low cumulus drifted up from the southeast, the air did not feel like it was coming from the cold Atlantic off Cape Cod, but rather from the warm Gulf Stream off Georgia.

In other words, while the map might say the high had retreated to the Gulf of Mexico and the front was still south of us, my lying eyes were telling me the Bermuda High was back, which was exactly what my old bones felt would happen.

Perhaps I am reverting to a more primitive way of forecasting.  Back when I was a boy they had no satellites and very few weather balloons with which to measure upper atmospheric conditions. Meteorologists pestered airline pilots for any information they could give about conditions aloft.  I can still remember the amazement people displayed the first time a newspaper showed a picture of a hurricane seen from outer space, (perhaps Donna in 1960 or Ester in 1961.)

Back in those days meteorologists paid much more attention to air masses and their source regions.  The first maps I looked at as a kid had mysterious letters by the “H” of a high pressure, and when I pestered I learned they were initials for where the air mass came from, as meteorologists knew a polar maritime air mass had different qualities than a polar continental air mass. Likely that is the reason I paid attention to the Bermuda High, even when it didn’t appear on the weather map any more.  It might not exist as a nice round circle of isobars, but its associated air mass didn’t just vanish.

Sometimes the boundary of an air mass is neatly shown by a clear-cut front, but the fronts eventually fade and vanish from maps, however as a boy I kept drawing where I felt the boundary was, as a “ghost front.”  I had much more time to do such things, as a spoiled kid, and I would insist on keeping track of an air mass even as it was stretched and elongated by surrounding forces.  For example, although a polar high starts out as a pure mass of northern air, the south winds on the west side bring north the bulge of a tropical air mass, even as the north winds on the east side brings south the cooler air mass, so the high is soon two air masses, which looked like a yin-yang symbol on my boyhood maps.

I remember one time I painstakingly tracked an air mass, (using the maps in “Weatherwise” Magazine,) until (on my private map) the air mass was stretched out to a elongated strip, and the top of the strip was sucked into a big gale, which then occluded, folding my air mass over like batter in a mixing bowl. Just then one of the early satellite picture came out, (because the gale made the news,) and to my great delight the pictured clouds very closely resembled my stretched, twisted and distorted “air mass.”

I no longer have the time to dwell on maps to that degree, and envy meteorologists who get paid to do so.  For me, in my current life, the time I spend dwelling on maps is a bit like the time I spend playing solitaire;  (time I feel guilty about, for I should be doing chores and not goofing off,) however the time I spent as a youth impressed me with some interesting things air masses did, when you bothered keep track of them.

One thing I noticed was that cool air masses don’t stay cool, if they come south. They heat up.  As they warm they are less able to be cold, heavy air sinking; they don’t press down as much, and eventually they don’t press down at all, because the air is heated to a degree where it starts to rise like a hot air balloon.

As I boy I noticed this as polar highs came down and headed off the east coast.  Each day they were less high; their central pressure was lower.  If they made it off the coast the pressure stopped dropping, and could even rise, for by then the air they held was warmer than the Atlantic, and would be cooled and again start sinking, as they merged with the Bermuda High (and in a sense strengthened it.)  However not all high pressure air masses made it to the ocean.  If they dawdled over the land too long they stopped being cool air pressing down, and stopped existing as a high pressure on a map.  Instead they became a general area of rising air and low pressure, and, because I knew of no name for such an air mass, I decided to call it a “Sog,” because it was juicy air and often brought soggy weather.  Furthermore, in the autumn, a “Sog” often turned into a pathway for an autumnal gale roaring up the east coast, so I paid attention to them.

Then I ran out of time and money and people to mooch off, and had to get a real job, and my study of maps went on hold for decades.  Not that I didn’t look at maps every chance I could, but I didn’t have time to dwell on them in the way I once did. However certain boyish perceptions stuck with me, and the concept of a “Sog” Is one of them.

Therefore when the Bermuda High extended to the west last week the boy in the back of my mind noted a large part of the high was dawdling over land, and whispered that the high pressure was likely to turn into a “Sog.”

And this morning, as others see a low pressure moving up over New England, I don’t see a low as much as I see a warm juicy high that isn’t high any more, called a “Sog.”

July 22 rad_ne_640x480 (1)

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s