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The first official forecast was issued Feb. 19, 1871, and gave a synopsis of existing weather throughout the country, and the probable change during the succeeding 24 hours. It?s interesting to note that the term "probabilities," which was replaced in 1876 with "indications" and in 1889 with the more familiar "forecast," perhaps better reflects the varying degrees of uncertainty inherent in all weather prediction, even today. The first forecast and map were based on data from a sparse network of a few dozen stations, only a handful of which lay west of the Mississippi.
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As busy as this hurricane season has been with 12 hurricanes, the United States did not get one hit. That is unprecedented. Since 1900, there has not been a hurricane season with 10 or more hurricanes without one striking the U.S. This season two hurricanes struck Canada, there were two landfalls in Belize and one in Mexico, but not one in the United States. The weather patterns were favorable for us this year. The Bermuda high was located further east than usual, low pressure over the East Coast steered storms away from the U.S and high pressure near Texas kept Alex in Mexico and other storms well south of the United States.
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Hurricane Irene hit the United States in 1999 and, 22 hurricanes later, Lili in 2002 made landfall in the U.S. There were 17 consecutive hurricanes that avoided the United States between Hurricane Allen in 1980 and Alicia in 1983, placing our current streak of 18 hurricanes in second place. Historically, one in four Atlantic hurricanes strikes the U.S. as a hurricane.
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Nobel Laureate Irving Langmuir thought it might be possible to increase rainfall by seeding the clouds from below with an updraft carrying finely ground salt particles (sodium chloride). In the clouds, condensation of water vapor onto the hygroscopic particles would initiate the formation of raindrops. A rain machine was built, which consisted or a horizontal metal cylinder about 4 feet in diameter and 10 feet long, and it was lined with firebrick. Hundred-pound salt particle bags were injected into the machine and blown rapidly upward through the pipe. There was never any evidence that this produced rain on the island.
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Forecasting accuracy has improved tremendously in the last 20 years and it can be argued that the most important advance in technology is the lead time with tornado warnings. Also the percentage of tornado warnings that resulted in confirmed tornado events, known as the probability of detection, increased from 40% in 1987 to 80% today.
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The pressure usually lowers when a cold front moves in. In fact, some people who've had knee surgery or older people can sometimes "feel" the pressure lowering. You'll often hear, "I know it's going to rain today, my bones hurt." A doctor I know calls it "barometric ache" or "rain pain."