"United States, which is home to the most extensive weather forecasting infrastructure in the world, around a third of severe weather predictions still prove wrong...The false-alarm rate for tornadoes continues to hover at about 70 percent, while the average warning time has only increased from about 10 minutes in the mid-1990s to 15 minutes today."
"When the earth warms in the spring and summer months, hot wet air rushes upward in columns, where it collides with cool dry air, forming volatile cumulus clouds that can begin to swell against the top of the troposphere, at times carrying as much as a million tons of water."
""convective available potential energy," or CAPE — a measure of how much raw fuel for storms the sky contains."
"as a storm travels along hot, saturated ground, its base tends to spread out and flatten, sucking up all available energy. The more it draws in, the faster and stronger the vacuum becomes, forming a narrow shaft of rushing air at the center of the storm, or updraft...each of the storms had generated such large, powerful updrafts that they'd eventually merged together and begun to spawn other, smaller updrafts, creating what's called a "mesoscale convective system" — in short, a giant, organized complex of perhaps 50 or more, which becomes self-sustaining as it germinates more and more offspring. Most M.C.S.s on the Great Plains take about four or five hours to form; this one, according to time stamps, materialized in less than 30 minutes...And because water produces heat as it condenses at altitude, the added moisture accelerates the process further."
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