Thomas Jefferson and weather

It was a warm and pleasant 4th of July weekend across the Inland Northwest as many enjoyed celebrating our nation’s 250th anniversary.

One of our founding fathers, the primary author of the Declaration of Independence, and our third U.S. President, Thomas Jefferson, was one of the first and most detailed weather observers in the U.S. For more than 50 years, he kept detailed meteorological journals that documented temperatures, wind direction, rainfall, cloud conditions, and other atmospheric observations. He carefully assembled information on Virginia’s weather and made his own observations at Williamsburg and Monticello.

Thomas Jefferson’s commitment to scientific observation made him one of the pioneers of American climatology and left behind a valuable record that scientists continue to study today. According to a website that describes Jefferson’s efforts, www.molnticello.org, his meticulous observations appeared in “Notes on the State of Virginia,” which was published in 1785.

Jefferson's interest in weather began while he was a student at the College of William & Mary during the 1760s. Influenced by Enlightenment ideals, he believed that careful observation of the natural world could improve agriculture, science, and everyday life.

Jefferson measured temperature multiple times each day using thermometers imported from Europe and noted wind direction, precipitation, cloud cover, humidity, and significant weather events. Despite the instrument’s simplicity, they were highly accurate for their time. His primary tool was a mercury thermometer. He also recorded barometric pressure when instruments were available, observed wind direction using weathervanes, and described cloud formations and precipitation in detailed notes.

His records stretched from 1772 until just days before his death in 1826. This made them one of the longest continuous weather records in early American history.

Jefferson claimed that he didn’t need a maximum-minimum thermometer because he rose every day at dawn, which he considered the coldest time of day. He made two observations a day, one early in the morning and the other in the afternoon around 3 to 4 p.m. From 1776, Jefferson kept mostly consistent and continuous record of his weather observations in America, in Europe when he was overseas, and even in the mid-Atlantic. From his travels and observations, he found that Virginia’s climate was the “envy to every part of the world.”

Jefferson saw practical value in weather observations, especially for agriculture. As the owner of a large plantation, he understood that successful farming depended on understanding seasonal weather patterns. His records helped identify the timing of frosts, droughts, heavy rains, and growing seasons. He hoped that systematic weather observations collected across different regions would eventually improve agricultural planning and increase crop production.

Jefferson also recognized the importance of long-term climate records. He frequently compared yearly temperatures and precipitation, searching for patterns and trends. Although modern statistical methods were not available, he determined that climate could only be understood through observations collected over many years. His notebooks represented one of the earliest attempts in North America to distinguish between short-term weather and long-term climate, which is still used by historians.

Jefferson never found his own equal in committed and unfaltering attention to the details of his climate. However, his dream of simultaneous observations across the land is realized today. Monticello, Va., is one of about 12,000 weather stations operated by the National Weather Service, which has named Jefferson as the "father of weather observers."

Coeur d’Alene has been fortunate to have its own dedicated weather observer, Climatologist Cliff Harris. In the 1990s, Cliff lived in Hayden prior to relocating to Vermont, where he also took daily observations. Since his return to Coeur d’Alene in 2003, he has recorded the most detailed daily observations for a region where reliable data was limited. He also compiled records for Coeur d’Alene going back to 1895 and these records are used daily in the Coeur d’Alene Press weather page.

Today, personal weather stations are continuously popping up across North Idaho and the rest of the world. Detailed, temperature, precipitation, wind, humidity and other data are accessible on websites such as www.wunderground.com, that show detailed observations about every 5 minutes. Jefferson’s dream was to establish more dedicated weather observers across the young United States. Today, there are over 250,000 personal weather stations worldwide and the number climbs each day.

In terms of our local weather, the drier than normal weather pattern is expected to continue for much of July. With the strengthening El Nino in the waters of the south-central Pacific Ocean, precipitation in Coeur d’Alene and surrounding areas will likely continue to be below average levels well into August along with high fire danger levels. The exception would be a strong thunderstorm that drops a lot of rain at one time. It’s also possible that we could see an increase of moisture from south later in August or September due to a stronger sub-tropical jet stream.

So far, we have escaped the blistering hot temperatures that much of the U.S. and Europe have experienced. After a very warm to hot start to the week, high temperatures should be mostly in the 80s around the middle to the end of the week. Readings should be very warm to hot as we head toward the end of the month.

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Contact Randy Mann at [email protected].