Today we’re talking about an important organization in American history: the National Weather Service. Weather, of course, has always been important to mankind, whether they be farmers or not. Many of our Founding Fathers were avid weather enthusiasts. While he was helping draft the Declaration of Independence, Thomas Jefferson bought a thermometer from a local Pennsylvania, and a few days later, bought a barometer from the same merchant—one of the only ones in America at the time. He noted that the high temperature in Philadelphia on July 4, 1776 was 76 degrees Fahrenheit. Jefferson made regular observations at his plantation, Monticello, from 1772 to 1778. George Washington also took regular weather observations; the last such entry in his diary was made the day before he died.
During the early and mid-1800s, weather observation networks began to grow and expand across the country. The telegraph was largely responsible for the advancement of meteorology during the 19th Century. With the help of this innovation, weather observations form distant points could be collected, plotted, and analyzed at one location. The Smithsonian Institution supplied weather instruments to telegraph companies and established an extensive observation network. By the end of 1849, 150 volunteers throughout America were regularly reporting their weather observations to the Smithsonian. By 1860, 500 stations were providing daily telegraphic weather reports to the Washington Evening Star, and as the network grew, other existing systems were gradually absorbed, including several state weather services.
The advancement of this meteorological network was interrupted by the Civil war, but in 1869, the telegraph service again began collecting weather data and producing weather charts. The ability to both observe and display weather information, thanks to the telegraph, quickly led to initial efforts toward the next logical advancement: the forecasting of the weather. However, the ability to observe and forecast weather over much of this huge country required a level of organization which could only be accomplished by a government agency.
Assuming your story takes place after 1870, your characters would have been familiar with the National Weather Service, or at least its forecasts and warnings. If they worked the land, they would have relied on those forecasts on a regular basis, likewise if they worked anywhere that the weather could impact their livelihood.