Aug 3, 2018 By Jack Hughes for The 3 min read

We all know the story of Ben Franklin and his kite. In addition to his experiment with electricity, he also kept a record of the weather. Since he traveled often and for long periods of time, his weather data did not have much consistency.

Thomas Jefferson on the other hand grew up with an obsession about the weather and kept weather records for most of his life. When he set in motion the Lewis and Clark expedition to explore the West, he insisted on a daily weather log and detailed information concerning weather and plants along the route. His “Weather Memorandum Book” is part of the history of his beloved home, Monticello near Charlottesville, Virginia.

Early colonists from England assumed the Virginia climate they were traveling too would match up by latitude to that of Europe and be comparable to Spain and Portugal. Europe is moderated by the Gulf Stream and I doubt they even knew about this ocean current and its effect on the weather. Settlers arriving here found a completely different climate — freezing cold, ice and snow, along with heat and humidity.

In spite of this, Jefferson was convinced that the new climate would be superior to that of Europe and he set out to prove it via his detailed weather observations. He invested in a weather vane to determine wind direction, a thermometer for recording temperature and a rain gauge to measure rainfall. Lastly, he purchased a barometer to use with the wind vane and his knowledge of clouds to actually forecast upcoming weather.

This winter, I was able to purchase a beautiful brass barometer at a flea market for $2. It had come off of a boat and uses millibars instead of inches to display the barometric pressure. A rising barometer indicates sinking air and fair weather where as a falling barometer indicates rising air and the approach of a storm. Even today with all the scientific equipment, a good barometer will still give you a pretty good forecast of short term weather changes.

Like Jefferson, I check my barometer several times a day. From his observations, Jefferson learned that his home site could expect an average of 46 inches of rain per year. Two hundred years later, the average is 47 inches per year. What Jefferson didn’t expect was that all weather averages also include the extremes, the flooding rains along with the extreme dry periods.

Jefferson insisted on building his home on a place he called “Montalto” or “High Mountain.” Almost all homes of the day were built along streams or rivers to insure adequate water supply. Although there were springs on the property, the well for the house took 46 days to dig and had to go through 65 feet of mountain rock. This was more than double the red clay soils of Virginia’s lower elevations.

The dry spells that make up Virginia’s average rainfalls included 7 years when the well went dry causing lots of problems for the staff and devastated crops. Even his four water cisterns that were built into the home to provide 600 gallons of fresh water each day from rooftop drains never worked properly and constantly leaked. While he was dead on about rainfall averages, he was overly optimistic about having the needed rainfall to grow the crops and for much of his life, the lack of rain thrust Monticello into hardship.

Information of the well and house taken from the book “Rain” by Cynthia Barnett.