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http://www.newscientist.com/article/mg20026864.900-lightning-strikes-give-bl
izzard-warning.html
Lightning strikes give blizzard warning
A FLASH of lightning during a snowstorm may be nature's way of signalling
that the worst is yet to come.
The combination of snow, lightning and muted thunder occurs occasionally in
storms across the temperate regions of North America, Europe and Asia, often
near lakes or cyclones. Eyewitness accounts of these rare events, known as
"thundersnows", date back thousands of years to ancient China, and suggest
that lightning tends to strike in parts of the storm where the most snow is
falling.
To verify such accounts, Patrick Market and Amy Becker at the University of
Missouri, Columbia, studied 1000 lightning strikes in 24 thundersnows. They
had previously shown that bigger snowstorms tend to produce more lightning,
reinforcing the expectation that lightning would coincide with the heaviest
bands of snow.
In fact they found that lightning tended to strike about 15 kilometres
downwind of the heaviest bands of snow, so the heavy snow did not arrive
until later (Geophysical Research Letters, DOI: 10.1029/2008GL036317
<http://dx.doi.org/10.1029/2008GL036317> ). The finding may give
meteorologists a way to predict snowstorm behaviour in near real time. Joe
Schaefer of the National Oceanic and Atmospheric Administration in Norman,
Oklahoma, says this is difficult with existing techniques, as "unlike rain,
snow doesn't show up well on our current radar systems".
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