Pick a good one!

https://en.wikipedia.org/wiki/February_9

1870 – US president Ulysses S. Grant signs a joint resolution of Congress establishing the U.S. Weather Bureau.

https://www.weather.gov/timeline

"George Washington also took regular observations; the last weather entry in his diary was made the day before he died.

During the early and mid-1800's, weather observation networks began to grow and expand across the United States. Although most basic meteorological instruments had existed for over 100 years, it was the telegraph that was largely responsible for the advancement of operational meteorology during the 19th century. With the advent of the telegraph, weather observations from distant points could be "rapidly" collected, plotted and analyzed at one location."