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Dear Tom,
What is the time range for the word “tonight” in a weather forecast, and similarly what is the time range for “today” in the forecasts?
—Margo Finnegan
Dear Margo,
“Tonight” in a weather forecast refers to the period from 6 pm to 6 am Central Standard Time (and from 7 pm to 7 am Central Daylight Time). “Today” is similarly defined as extending from 6 am to 6 pm CST and from 7 am to 7 pm CDT. Many people think of “tonight” as referring to the hours of darkness following the daylight period immediately preceding it, categorizing the hours of daylight after 7 pm CDT in the summer months as still part of the preceding day, but realizing that technically those hours are part of the nighttime hours.