A data frame with weather-related variables for several world cities.
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city
	 
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City name.
	 
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date
	 
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Date.
	 
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year
	 
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Numeric year.
	 
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month
	 
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Numeric month.
	 
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day
	 
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Numeric day.
	 
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high_temp, avg_temp, low_temp
	 
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High, average, and low temperature for the day in degrees F.
	 
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high_dewpt, avg_dewpt, low_dewpt
	 
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High, average, and low dew point for the day in degrees F.
	 
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high_humidity, avg_humidity, low_humidity
	 
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High, average, and low relative humidity.
	 
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high_hg, avg_hg, low_hg
	 
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High, average, and low sea level pressure in inches of mercury.
	 
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high_vis, avg_vis, low_vis
	 
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High, average, and low visability for the day in miles.
	 
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high_wind, avg_wind, low_wind
	 
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High, average, and low wind speed for the day in mph.
	 
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precip
	 
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Precipitation for the day – a character vale; T means "trace amount".
	 
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events
	 
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Character string naming weather events on the day (Rain, Fog, Snow, etc.)