Thomas Jefferson: Founding Father of Weather Observers

As the main author of the Declaration of Independence and the third President of the United States, Thomas Jefferson is regarded as one of this country’s Founding Fathers. He was also an astute and systematic weather observer.

Portrait of Thomas Jefferson by Rembrandt Peale, 1805. Credit: NYHS

In the summer of 1776, Jefferson was in Philadelphia, PA to sign the Declaration of Independence.  While there, he purchased a thermometer and a barometer – new and expensive weather equipment at that time. For the next 50 years, he kept a meticulous weather journal.  He recorded daily temperature data wherever he was – at home in Virginia or while traveling.

On July 4, 1776, Jefferson noted that the weather conditions in Philadelphia were cloudy with a high temperature of 76°F.

In an effort to understand the bigger picture of climate in America, Jefferson established a small network of fellow observers around Virginia as well as contacts in a few other states. According to records at Monticello, his estate in Virginia, he hoped to establish a national network for weather observations. While this plan did not come to fruition during his lifetime, today’s National Weather Service considers him the “father of weather observers.”

Happy Independence Day!

An excerpt from Thomas Jefferson’s Weather Journal, July 1776. Credit: NCDC

How Rainbows Form

St. Patrick’s Day is a holiday often associated with images of rainbows promising a path to a leprechaun’s pot of gold. For most people, however, just spotting a rainbow is enough to brighten a day.

These amazing displays of nature form when raindrops, which act like prisms, scatter sunlight. To see one, an observer must be facing a moisture source like rain or mist with the sun at their back. The sun also needs to be at a low angle in the sky, less than 42° above the horizon. The lower the sun angle, the more of a rainbow’s arc will be visible.

Refraction and reflection inside a raindrop. Credit: Met Office

Passing from the air into a denser raindrop, the light slows and refracts. Since the different wavelengths of light bend by different amounts, the white light is dispersed into the colors of the visible spectrum: red, orange, yellow, green, blue, indigo, and violet. Red, which has a long wavelength, is refracted the least and is always on the top of a single rainbow. Violet, with a shorter wavelength, is refracted the most and is always on the bottom.

The light also needs to reflect off the back wall of the raindrop towards the viewer at the critical angle of 48° before it refracts again when it re-enters the air. A lesser angle will let the light pass through the raindrop and a larger angle will allow the light to reflect straight back out of the drop.

A double rainbow is seen when the light reflects twice inside the raindrop. Since each reflection weakens the intensity of the light, the second bow appears dimmer. The order of the colors is also reversed, with blue on top and red on the bottom.

Rainbow and faint second rainbow form after a rainstorm in Bermuda. Credit: Melissa Fleming

Weather and Art: “Love of Winter”

Today is Valentine’s Day, a holiday when chocolate treats and images hearts abound. But for me, it is George Bellows’ Love of Winter that always comes to mind as we mark the mid-point of what is usually New York City’s snowiest month of the year.

A longtime personal favorite, this 1914 painting captures the spirit of those who embrace the season. Filled with the blurred movement of skaters on a frozen pond and accented with spots of bright color that pop against the snow, it conveys the joy of being out in nature on a cold winter day.

While Bellows is better known for depicting scenes of boxing matches and urban life, art historians say he enjoyed the challenge of painting the varied lighting conditions produced by a snow-covered landscape. In fact, he wrote a letter to a friend in January 1914 complaining about the lack of snow in the New York City area that winter. He said, “There has been none of my favorite snow. I must paint the snow at least once a year.” Then, about a month later, his wish for snow was granted and this painting was created.

Love of Winter is part of the Friends of American Art Collection at the Art Institute of Chicago.

“Love of Winter”, 1914 by George Bellows. Collection of the Art Institute of Chicago

Why Today is National Weatherperson’s Day

Today is National Weatherperson’s Day in the United States. While not an official federal holiday, it is a day to recognize the work of all individuals involved in the field of meteorology – not just prognosticating groundhogs.

Dr. Jeffries

According to the NWS, today’s designation honors the birthday of Dr. John Jeffries who was one of America’s first weather observers. Born in 1744, this Boston-based physician had a deep interest in weather and kept detailed records of daily conditions from 1774 to 1816. He also took the first known upper air observations from a hot air balloon in 1784.

Since the 18th century, the weather enterprise has grown by leaps and bounds. Utilizing radar, satellites, and computer models, meteorologists today provide forecasts and warnings to the public in an effort to protect lives and property. Beyond this vital service, however, weatherpersons are simply fascinated by the workings of the atmosphere and are always seeking to improve their understanding of its complex processes.

Credit: National Today

New Year’s Eve 2017: Second Coldest on Record for NYC

New Year’s Eve 2017 was one for the record books in New York City.

The midnight temperature in Central Park was a mere 9°F, marking the city’s second coldest New Year’s Eve on record. The coldest was in 1917 when the temperature was only 1°F. The normal low for this time of year is 28°F.

These unusually frigid conditions are the result of a deep dip in the jet stream and a lobe of the polar vortex reaching southward over much of the eastern US. They are expected to remain in place for the near future.

Source: NWS

The Chances for a White Christmas

The Holidays are here and many people are dreaming of a White Christmas. The likelihood of seeing those dreams come true, however, is largely dependent on where you live.

According to NOAA, a White Christmas is defined as having at least one inch of snow on the ground on December 25th. In the US, the climatological probability of having snow for Christmas is greatest across the northern tier of the country. Moving south, average temperatures increase and the odds for snow steadily decrease.

Here in New York City, the historical chance of having a White Christmas is about 12%. This low probability is largely due to the city’s proximity to the Atlantic Ocean, which has a moderating influence on the temperature. This year, with an area of low-pressure developing off the coast and cold arctic air moving in from the northwest, snow is a possibility for the Big Apple. It all depends on the track of the low.  If it stays close to the coast, NYC will see rain or a wintry mix while inland areas will get snow. If the low moves further off-shore, the cold air will be able to push eastward and NYC will get snow for Christmas.

Snow or no snow, The Weather Gamut wishes you a very Happy Holiday!

The historical chances for a White Christmas across the continental US. Image Credit: NOAA

Weather and the NYC Macy’s Thanksgiving Day Parade

The Macy’s Thanksgiving Day Parade is a long-standing holiday tradition in New York City.  For 91 years, it has marched rain or shine. Nevertheless, the weather has been a factor in the event several times over the years.

Famous for its giant character balloons, high winds are the main weather challenge for the parade. According to city guidelines, the multi-story balloons cannot fly if there are sustained winds in excess of 23 mph or gusts higher than 34 mph. These regulations were put in place following a 1997 incident where gusty winds sent the “Cat in the Hat” balloon careening into a light post, which caused debris to fall on spectators.

The only time the balloons were grounded for the entire parade was in 1971 when torrential rain swept across the city. In 1989, a snowstorm brought the Big Apple a white Thanksgiving with 4.7 inches of snow measured in Central Park. The parade marched on that year but without the “Snoopy” and “Bugs Bunny” balloons as they were damaged by high winds earlier that morning.

This year, the wind is not expected to be a problem. Temperatures, however, are forecast to be a bit chilly – mostly in the 30s during the parade hours. So, bundle up if you are planning to be outside along the route.

Marching from West 77th Street to West 34th Street in Manhattan, the 91st Annual Macy’s Thanksgiving Day Parade is scheduled to begin at 9 AM on Thursday morning.

Happy Thanksgiving!

Paddington Bear Balloon floats down 6th Ave in Macy’s Thanksgiving Day Parade. Credit: Macy’s

Thomas Jefferson and the Weather in Philadelphia on July 4, 1776

Thomas Jefferson is well known as one of the Founding Fathers of the United States, but he was also an astute and systematic weather observer.

Portrait of Thomas Jefferson by Rembrandt Peale, 1805. Credit: NYHS

In the summer of 1776, Jefferson was in Philadelphia, PA to sign the Declaration of Independence.  While there, he purchased a thermometer and a barometer – new and expensive weather equipment at that time. For the next 50 years, he kept a meticulous weather journal.  He recorded daily temperature data wherever he was – at home in Virginia or while traveling.

On July 4, 1776, Jefferson noted that the weather conditions in Philadelphia were cloudy with a high temperature of 76°F.

In an effort to understand the bigger picture of climate in America, Jefferson established a small network of fellow observers around Virginia as well as contacts in a few other states. According to records at Monticello, he hoped to establish a national network for weather observations. While this plan did not come to fruition during his lifetime, today’s National Weather Service considers him the “father of weather observers.”

Happy Independence Day!

An excerpt from Thomas Jefferson’s Weather Journal, July 1776. Credit: NCDC

Why Earth Day Matters

Every day is Earth Day, as the saying goes. But, today marks the official celebration.

The first Earth Day – spearheaded by Senator Gaylord Nelson of Wisconsin – was held on April 22, 1970.  An estimated 20 million people attended rallies across the US to protest against rampant industrial pollution and the deterioration of the nation’s natural environment. Raising public awareness and shifting the political tide, these events helped put environmental issues on the national agenda. They led to the creation of the EPA and the passage of the Clean Air Act, Clean Water Act, and the Endangered Species Act.

This year, with the rise of “alternative facts” and the Trump Administration’s rollback of US climate change policies, the date is more significant than ever.  In the spirit of the original event, concerned citizens across the US are gathering for marches in support of science and fact-based environmental policies.

Blue Marble 2012. Credit: NASA

 

Easter 2017: Second Warmest on Record for NYC

The calendar said Easter, but it felt more like the Fourth of July in New York City on Sunday. The temperature in Central Park soared to a sweltering 87°F, which is a staggering 25°F above average.

According to the NWS, this was the second hottest Easter on record for the Big Apple. The warmest was April 18, 1976, when the temperature hit 96°F. Unlike Christmas, Easter falls on a slightly different date every year. It is the first Sunday after the first full moon that occurs after the spring equinox.

While the heat was not ideal for the holiday’s famous chocolate eggs, the city’s parks were filled with people enjoying the warm weather. However, if you are not quite ready for summer, fear not. More spring–like conditions are expected to return this week.

Credit: NWS