It's not the heat. It's the humidity.
And it may not be El Nino we have to worry about. It may be La Nina.
That, at least, is the informed opinion of University of Tennessee climatologist
Dr. Joanne Logan. She's taken a long, hard look at the jet stream and the
flip-flopping pressure zones, and she's not impressed. Not this year, anyway.
Oh, she's not denying the floods in South America and the drought in Australia.
But this is a local paper. We want local news. How many snow days? How much
kitty litter in the trunk of the car? How many shelves of canned chili?
How much weather hype can we reasonably expect here?
Plenty.
Local forecasters are unanimous on one point. If we have a bad winter, it
will be chalked up to El Nino. So will a mild winter. So will anything in
between.
"It's almost more of an art than a science, predicting weather," says Logan.
And it rises to the level of high art in El Nino seasons, which occur every
three to seven years, causing climate chaos. This is because prevailing winds
usually blow from east to west, from the coast of South America towards Australia
and Indonesia. In El Nino years, however, the winds die down, causing water
temperatures in the Eastern Pacific to rise as much as 10 degrees. Before
1950, this phenomenon was only of interest to the local South American fishermen.
Over the past 20 years, scientists have studied El Nino's proposed connections
to climate anomalies that occur before, during, and after an El Nino event.
Flooding in areas of South America and droughts in Indonesia and Australia
are common during El Nino years.
La Nina, on the bother hand ("it's the anti-El Nino," Logan explains), does
not necessarily follow El Nino. It may skip a season. While El Nino produces
a dramatic warming of Pacific waters, La Nina is a sudden cooling.
"It almost looks like La Nina might cause more weather effects in Tennessee
than El Nino," Logan says. "Some experts say that because this particular
El Nino has peaked and is tapering off quickly, we could have a dramatic
swing the other way—towards a La Nina." What would that mean for East
Tennessee? Hard to say. "That situation has only happened three times in
the years weather has been systematically reported here. To base a prediction
on something that has only occurred three times would be really stretching
it."
On the other hand, there have been 20 recorded El Ninos—which should
give us a pretty good idea of what to expect.
Except that it doesn't. Some of the worst weather in the Knoxville area has
hit during non-Nino years. The blizzard of '93 was a case in point. So was
that January day in '85 when Knoxville was the coldest place in the U.S.
at 24 below. The ice storm of 1982, on the other hand, happened during an
El Nino.
Logan's survey of past El Nino years in Knoxville shows a slight increase
in snowfall in January. But slight, she says, is the operative word—"only
a few inches."
"We went back and looked at the last seven El Ninos, and what we came up
with is that you can just about have anything," says Jerry McDuffie,
meteorologist in charge at the National Weather Service office in Morristown.
"If you live on the Gulf Coast, you can figure on more rain than normal.
Parts of Australia and Indonesia go into drought. These things happen with
every El Nino.
"But Tennessee seems to be in the middle between the wetter southeast and
the drier north."
Information posted on the National Weather Service Web site
(www.srh.noaa.gov/mrx/) underlines the unpredictability of local El Nino
behavior.
"There appears to be no definite or clear-cut effect for the weather across
our area due to El Nino," writes Joanne Labounty. "Four of the last six El
Ninos had above normal precipitation totaled for the entire El Nino period.
But there were dry to very dry periods during those years as well. It appears
that the type of weather we can expect this winter and in the months that
follow is like any other year across East Tennessee. Anything can happen."
Local meteorologists agree that there's more than enough ambiguity to go
around.
"The thing about El Nino is that it's been going on for hundreds of years,"
says Matt Hinkin of WATE TV. "I don't think it's anything to panic about.
I've had many more calls about it than in past El Nino years, and that's
because it's been publicized more. And it's been publicized more because
we know more about it."
But while scientists may have more sophisticated methods of tracking weather
systems, misconceptions still abound.
"People automatically think we're going to have a bad winter," says Hinkin.
"We could go through the whole winter and have very little snow and then
get a big storm and everyone will say it's a bad winter. If you look at weather
over years and years, it seems to even itself out. We may go through bad
years, then we'll have mild years. I will say the big snows seem to happen
in odd years—1993, 1995. And '97 is an odd year."
Scott Blalock of WVLT TV says people tend to mistake El Nino for one big
storm.
"It really doesn't have anything to do with one storm," Blalock says. "It
means that a body of water is abnormally warm over a huge area. That influences
where the weather patterns are. It's as if I came into your house and rearranged
the furniture. This type of arrangement is conducive to more big storms,
more wet weather."
So does that mean we're looking down the barrel of a long, hard winter here?
"When you say a hard winter, a lot of folks think of bitter cold and snow,"
he says. "I don't think it will be harsh cold, but rainy and drizzly and
long, with some periods of ice and snow."
Blalock's heard his share of weird theories about El Nino—everything
from the stock market plunge to increased psychic powers attributed to the
weather system.
"People get tense and look for answers," he says. "What better place to turn
than Mother Nature? It's certainly not us; we're all perfect. It must be
the weather."
"It's a global event, a regular cycle of warming and cooling Pacific waters,"
says Todd Howell of WBIR TV. "This is an unusually strong warming year. El
Nino provides more moisture for the Southern U.S. If you have more moisture,
you have a greater potential for increased precipitation."
So what's a weather watcher to do?
Helen Lane, venerable weather prophet of the Cumberland Plateau, has spent
decades tracking the seasons through signs in nature. Poor health prevented
her from filing her annual predictions with the Crossville Chronicle,
but friend Janie Holloway interviewed Lane earlier this month and reported
her forecast in the paper.
Six heavy fogs in August point to six heavy snows, Lane says.
Nino-Shmeeno. Stock up on kitty litter and chili. Looks like a long one.
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