Astronomical Refraction

By Dan Briscoe

February 15, 2019

In the picture above the sky was darkened for artistic value and to remove the distracting hazy sunset.  Location: Ocean Shores, WA. September 22, 2018 at 7:12:11 PM

We have all seen refraction when a stick is placed in the water at an angle and the stick appears to bend at the point where it enters the water.  Rainbows are another example of refraction where light is separated and refracted at different angles depending on its wavelength. We see refraction in many forms.

Astronomical Refraction, also known as Atmospheric Refraction, is when a celestial body (the sun, stars, moon, or planets), appears to an observer on earth to be in a slightly different position than its actual geometric position. The actual position of the sun when this picture was taken was below the horizon, or nearly so. When a celestial body is low on the horizon, the light from it has to travel through the Earth’s atmosphere, which causes it to be refracted or bent. Because of the low position in the sky, the light must pass through much more of the Earth’s atmosphere than when the object is higher in the sky.

Astronomical Refraction is greatest at the equator. On a typical day, the setting sun is visible 2 minutes after it has geometrically passed below the horizon. Humidity, temperature, air pressure, and air pollution affect the refraction properties of the atmosphere.

The picture above was taken 2 minutes and 5 seconds before the upper lobe of the sun disappeared below the horizon.  The picture below was taken just as the lower lobe touched the horizon at 7:11:11 PM PDT, September 22, 2018, exactly one minute before the top photo was taken.  As the sun passes further below the horizon, the silhouettes of the clouds across the face of the sun began to get larger. They didn’t appear prior to the sun setting, but may have been lost in the haze. Cloud silhouettes appear larger as the sun sets; the clouds in this image are actually beyond the horizon and their image is being refracted along with the light of the sun.

Location, Ocean Shores, WA.  Lower lobe touched the horizon at 7:11:11 PM PDT, September 22, 2018. Refracted cloud silhouettes starting to appear across the face of the sun.

Navigators have long used sextants in celestial to measure the altitude of a celestial body relative to calculate their position on the surface of the earth.  . A sextant is a very precise optical device used to measureing degrees, minutes (60th of a degree), seconds (60th of a minute), and fractions of a seconds.  along with Geographical position can also be calculated using very precise time clocks and astronomical almanacs. geographical position can be calculated.  Yes, e Even with modern day navigation systems like GPS, celestial navigation is still used as a backup by ocean going sailors, but due. Due to refraction, celestial sights (measurements with a sextant) are not considered reliable or used  for measuring the position of when celestial bodies when they are low on the horizon.

Additional information may be found at:

The Golden Gate Weather Engine

By Dan Briscoe

February 17, 2019

Title Image – A fog-shrouded Golden Gate Bridge in San Francisco, California.
©Della Huff Photography,

“The coldest winter I ever spent was a summer in San Francisco.”  This quote, often erroneously attributed to Mark Twain, is nonetheless affirmation of a weather pattern many visitors to San Francisco have experienced firsthand.

The uneven heating of the Earth’s surface creates our weather. Examining the microclimate of San Francisco and the Golden Gate area helps to illustrate one characteristic of Earth’s global weather engine. San Francisco is unique in that summertime temperatures in the Bay Area can be over 100° F and yet when a cold fog blows in through the Golden Gate the temperature can drop as low as 50° F  down on the piers. A few miles southeast, the fog is gone and is the temperature is again over 100° F.

Before we explore San Francisco’s unique weather phenomenon, let’s first talk about air.  By volume, dry air contains 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.04% carbon dioxide, and small amounts of other gases.  Air is a gas and gases can compress or expand. As air is heated the molecules become more active, moving around and bouncing off each other. As this happens, they need more room to play and they get farther apart or less dense. In contrast to this, when air gets colder the molecules are more compact or dense. (In a future post, we will explore Boyle’s law where we will discuss the relationship of temperature, volume, and pressure of gas.)  

Water in a gaseous state – water vapor – is  generally invisible except when refracting light. Water vapor, can, however, be felt as humidity. Humidity, generally expressed as “Absolute Humidity” or “Relative Humidity” refers to the amount of moisture – water vapor – in the air. For this discussion, when we talk about humidity, we are referring to Relative Humidity,  which is a ratio of how much moisture is in the air compared to how much it can contain at the current temperature. In nature, 0% humidity is nearly impossible. All air has a certain amount of water vapor. As air heats up, there is more space between the molecules, allowing more room for more water vapor. When the air becomes saturated with water vapor (100% humidity), the dew point temperature is reached and clouds or fog will form. Warm the air up and it can hold more moisture and the clouds will go away.

Let’s look at the factors influencing the “San Francisco/Golden Gate Weather Engine”:

Cold Moist Marine Air

Predominant onshore flow from the northwest pushes the dense, cold, moist marine air up against the coastal mountain ranges. This airmass adopts the properties of the cool Pacific Ocean as it travels from the Gulf of Alaska or North China Sea.  Being dense and heavy, it doesn’t push up over the coastal mountains to form a high-pressure ridge.

Mountain Ranges

The Coastal Range mountains of California extend hundreds of miles along the coast from northern California to Santa Barbara. The Golden Gate sits at the mouth of San Francisco Bay in a gap between the  northern and southern Coast Ranges.

The Coast Ranges to the west and the Sierra Nevada to the east create a huge basin – 450 miles long and 40-60 miles wide – of hot air in the Central Valley. These two mountain ranges act as barriers, keeping the cool marine air out and the warm dryer air in the basin.

The Golden Gate

The narrow gap in the mountains at the mouth of San Francisco Bay is known as the Golden Gate. To the cool dense airmass held back by the coastal mountains, this is like a breach in a dam. The air rushes through this gap to the collide with the lower pressure of the warm air over San Francisco Bay and out to the Central Valley. The Golden Gate acts as a venturi, accelerating the air as it passes through the gap. It then quickly slows down after it has passed through the gap, and dissipates into the large expanse of the Central Valley. If you are unfamiliar with the term venturi, think of the shape of an hour glass. When a fluid or gas moves through the narrow passageway, it accelerates but the static pressure drops. Then as the opening gets bigger again the static pressure increases and the velocity drops. A similar process occurs at the Golden Gate: as the air decompresses going through the Golden Gate, it mixes with the warm air over San Francisco Bay. This warm air has a much higher capacity for containing water vapor. This decompression cools the mixed air and drops it to its dewpoint temperature, thus forming a dense fog bank. In the short distance between the Golden Gate Bridge and the Bay Bridge, the air warms up again and can hold all the moisture in the mixed air without being saturated. The fog disappears.

The California Central Valley

Most of the Central Valley is rich in agriculture.  The dark soils of the plowed fields have a very low heat capacity.  This means that the soil will heat up quickly with the energy from the sun.  Materials with a low heat capacity will also cool quickly as the source of heat is removed. Water, on the other hand, has the highest volumetric heat capacity of all commonly used materials. Therefore, an airmass over water is not heated as much from the ground radiation as it is over the dark soils of the Central Valley in the summer.

The southern end of the Central Valley is classified as desert grasslands. The San Juaquin Valley between Fresno and Bakersfield, which often sets record high temperatures, generates very powerful thermals that act like a vacuum cleaner sucking air from the Central Valley and lifting it far up into the atmosphere. This creates a surface low in the Central Valley and intensifies the flow of dense cold air through the Golden Gate.

Sneak Preview: Global Movement of Air and Weather

In a future post, we will examine Global air movement and weather patterns. Globally, air is moved in much the same way as described above. The sun heats up the earth along the equator and tropics, and the air expands and becomes lighter, creating a low-pressure area. This warm air rises high up into the atmosphere, and – while aloft – pushes out toward the cooler regions of the Earth. As it becomes cooler, it becomes heavier, and settles down to the Earth’s surface, creating higher pressure. This is a circulation of air on a global scale, but there is a lot more to it.  We will discuss this in a future post.. Stay tuned!

Satellite Image of San Francisco Bay,,
USGS public domain

Title Image – A fog-shrouded Golden Gate Bridge in San Francisco, California (© Della Huff/Alamy)

Reference links:

Winter Weather: Snow Squalls

Winter Weather: Snow Squalls

By: Marina Kobasiuk

Snow squalls are a specific type of winter storm that are not new, but predicting them has been difficult due to a variety of reasons. Squalls, no matter the precipitation type, are described as narrow bands of convective storms with intense winds. They form and dissipate quickly and can either track ahead of a larger system or be a localized event, but are often tied to strong cold fronts. As a result, the exact atmospheric conditions that can trigger their life cycle has been a focus by meteorologists in order to improve forecasting.

It can be easy for winter weather terminology to get confusing though, especially since snow squall forecasts were not issued by all weather service offices until recently. And they can often be compared to blizzards due to the similarities in what they do to visibility. These storms, however, are not exactly the same as blizzards due to their short life span. Blizzards require three hours or more of sustained winds and squalls will complete their passage in under an hours time. Squalls often are associated with precipitation, though if the snow accumulates can depend on the local conditions before the snow begins. Warmer surface temperatures can reduce accumulation but the speed and quantity can still result in inches of snow remaining after a storm has finished. Blizzards, however, can occur with or without snowfall since the necessary low visibility can come from falling snow, or previously deposited snow that is being blown back into the air by the constant winds and strong gusts.

These extreme conditions are brief but can cause significant damage and loss of life; notably on roadways where people are unable to take shelter and there is no way for people to accommodate for the sudden change in weather. In an effort to minimize this NOAA began testing a process of issuing warnings for snow squalls, which was why only selective offices were issuing these forecasts until the winter of 2018-2019 when the program went nationwide, just in time to get plenty of potential uses with the intense cold the nation saw with the trend of low temperatures and storms associated with the polar vortex in January. As the winter continues the weather service may or may not see more use of this particular warning, but now it can be used anywhere that these conditions may develop, and in an effort to keep people safer this is an excellent improvement to see in winter weather forecasting and safety.


“Snow Squall Warnings Now Available Nationwide.” National Oceanic and Atmospheric Administration,

US Department of Commerce, and Noaa. “Snow Squall.” National Weather Service, NOAA’s National Weather Service, 20 Apr. 2018,



The article below appeared in the January 13, 2012, edition of the Washington Post. Sunday, January 13, 2019, marks the 37th anniversary of a tragic aircraft accident in Washington, DC, Air Florida flight 90. The YouTube links that follow the article provide much more detail about this accident, including interviews with people who were at the scene.

Aircraft icing has been the cause of several aircraft accidents, with Simmons Airlines flight 4184 being another famous accident. It occurred on Halloween 1994 near Roselawn, Indiana.

As is the case in most airline accidents, many valuable lessons have been learned and applied in the wake of these accidents.

30 years after Air Florida crash, skies safer than ever

By Ashley Halsey III

January 12, 2012

This month and next, more than 2,600 jetliners will thunder down the same runway by the Potomac, bound for the balmy Florida sunshine.

If you are on board one of them, escaping Washington in winter, take heart that your departure is far safer than it was 30 years ago Friday, when a combination of blunders catapulted a plane from that runway into the 14th Street bridge.

The indelible chronicle of that snowy late afternoon began even as Air Florida Flight 90 sank into the Potomac. A TV crew that had been stuck in traffic jumped out to film the horror and the heroism for which the day is remembered.

The four people trapped by bridge traffic who died in their cars. The 74 crew members and passengers — three of them infants — killed in the crash. The passenger, Arland D. Williams Jr., who helped others escape the water and then was sucked under himself. And the bystander, Lenny Skutnik, who dived into the freezing water to save a drowning woman.

People who were touched by that day or caught up in the magnitude of the disaster will remember most of that. But 30 years after the fact, few people who cross the 14th Street bridge are aware that its formal name is the Arland D. Williams Jr. Memorial Bridge. And the 2.5 million people who take off from Reagan National Airport this winter will do so in the belief that the history of Jan. 13, 1982, can’t be repeated.

Experts say they’re right.

The lessons of that day and advances in training and technology over three decades have contributed to the safest era in aviation history. Although the skies are not risk-free, there hasn’t been a U.S. airline crash that killed more than 50 people since 2001.

National Transportation Safety Board investigators blamed the Flight 90 crash on a cockpit crew that didn’t de-ice the engines while awaiting takeoff and then relied on clearly dubious readings from instrument sensors that were clogged with ice.

The investigators said that although the captain, Larry Wheaton, and the co-pilot, Roger Alan Pettit, were cockpit veterans, they didn’t have much experience with winter weather. And they said that the plane sat on the taxiway too long, being pelted by snow and ice that fouled the critical leading edge of the wings and reduced the plane’s lift as it hurtled down a runway that ended at the Potomac.

* * *

The captain of a plane that taxied past as Flight 90 readied for takeoff commented to his crew, “Look at the junk on that airplane.”

Later he recalled: “Almost the entire length of the fuselage had a mottled area of snow and what appeared to be ice. . . along the top and upper side of the fuselage above the passenger cabin windows.”

* * *

There are at least three reasons that in 2012 your plane shouldn’t be covered with ice: better chemicals to keep the ice off, stricter regulations and better training for ground and cockpit crews.

“All three of those have evolved significantly over the last 30 years,” said Tom Hendricks, who flew for Delta Air Lines for 23 years before becoming senior vice president for safety, security and operations at Airlines for America, the trade group that until recently was known as the Air Transport Association.

Thirty years ago, Flight 90 was de-iced haphazardly by ground crews uncertain about the temperature, the NTSB report says. The plane sat waiting its turn for takeoff for 49 minutes after being sprayed with a de-icing chemical. It was snowing heavily.

De-icing chemicals have evolved since 1982, and new anti-icing mixtures developed in Europe were introduced in the 1990s. Applied after a de-icing, the liquid is thick enough to stick to the plane. It absorbs precipitation and then falls off as the plane gathers speed on the runway.

Pilots are now trained to use “holdover” tables that dictate how long they can remain on the ground after anti-icing fluid is applied.

“You’ve got to be airborne by that time, or you come back and you start the whole thing over again,” Hendricks said. “It’s incredibly structured. It used to not be that way. It’s very checklist-oriented. Pilots are highly trained in it.”

The Federal Aviation Administration has issued a series of regulations and directives since the 1980s governing use of de-icing fluids and training for pilots and ground crews. The most recent, released in August, requires that planes with de-icing systems be equipped with automatic cockpit alerts and that smaller commercial planes be retrofitted with ice-detection systems.

* * *

Conversation from the cockpit as Air Florida begins takeoff:

Co-pilot, watching instruments: “God, look at that thing. That don’t seem right, does it? Uh, that’s not right.”

Pilot: “Yes it is; there’s 80.”

Co-pilot: “Naw, I don’t think that’s right. Ah, maybe it is. . . .”

* * *

Thirty years later, few of the 26,000 passengers who take off from National on a typical day remember the details of the Flight 90 crash. But the people flying their planes do.

“Within the air crew world, this is a well-known accident,” said Jim Hookey, the resident expert on jet engines at the NTSB.

It was not the weight of the ice, the wait to takeoff or the slush on the runway that caused the plane to crash. For reasons no one will ever know, two pilots with little experience in winter weather failed to turn on heating systems that keep the idling jet engines warm.

Without that heat, something — almost certainly ice — clogged engine openings that are essential to determining how much thrust those engines are generating. As a result, the cockpit instruments told the pilots that the engines were generating far more power than they really were.

Because of those bad readings, when the plane failed to gain altitude, the pilots didn’t realize that throwing the throttle open would give them more lift.

“Up to about eight or 10 seconds before they hit the bridge, if they had just pushed the throttle [wide open], they probably would have buzzed the bridge, but they would have made it,” Hookey said.

That lesson, he said, has been learned throughout the industry.

“Crews now are not hesitant to jam the throttle to save the plane,” Hookey said. “There’s probably been a lot of airplanes that have been saved because of the errors that these guys made.”

* * *

Conversation in the cockpit as Air Florida struggles to get airborne:

Pilot: “Come on forward . . . forward, just barely climb. . . . Stalling, we’re falling!”

Co-pilot: “Larry, we’re going down, Larry . . .”

Pilot: “I know it.”

[Sound of impact.]

* * *

A driver stuck in traffic on the northbound 14th Street bridge:

“I heard screaming jet engines. . . . It was like the pilot was still trying to climb, but the plane was sinking fast. I saw the tail of the plane tear across the top of the cars, smashing some tops and ripping off others. . . . Once the tail was across the bridge, the plane seemed to continue sinking very fast, but I don’t recall the nose pointing down. . . . I saw the cockpit go under the ice. I got the impression it was skimming under the ice and water.”

* * *

Rescue crews and ambulances struggled through traffic to reach the scene on that snowy afternoon. The federal government had released its employees early, and roads were jammed. Then came word about 30 minutes later that a crowded Orange Line train had slammed into a concrete pillar near the Smithsonian station.

The first fatal accident in the history of Metro would injure 25 passengers and kill three others.

YouTube videos of the Air Florida flight 90 accident:

The First Experience –

Meeting Chris Cimino

Every meteorologist has a beginning; a moment that made them realize that weather was their passion. For some, it was a significant weather event. Others, it was discovering the science. For me, there was no one seminal moment, but a series of them in childhood.

Perhaps none was bigger than Read Across America Day in March 2002. It was my first chance to meet a broadcast meteorologist, thanks largely to my family and the local parent-teacher organization. His name – Chris Cimino, morning meteorologist at NBC 4 in New York City, just 40 minutes from my home in New Jersey. I still remember every moment of that day.

Chris was speaking to a class of fifth grade students, and I was called out of class. I was escorted to the library and to my surprise saw him there. I waited until he was finished with his talk and got the chance to shake his hand and talk to him briefly. While Chris did not know it at the time, it was a big moment for me, helping to show me that my dream could be possible.
We each have our own ways that led us to this field, this work, and this position in the weather enterprise. What’s yours? Your story is your history in the world of weather after all.

Why so windy in the winter?

By: Chris Michaels

Wind has been a big talking point in the eastern U.S. this past week, with multiple high wind alerts issued. It begs the question of why things get so windy, and who is usually the windiest city in the U.S.

This is where we get a little technical. Air tends to move from high pressure to low pressure, to essentially fill the void. An invisible force, called the Coriolis force, deflects the air to the right in the northern hemisphere.

Especially in the Mid-Atlantic states, that air tends to flow then from northwest to southeast. Since the air is moving over the Appalachian Mountains, it will then accelerate east of the mountains. This has lead to gusts of 40-60 mph at times in recent weeks.

Does that make the Mid-Atlantic one of the windier regions? No. Places like Rochester, MN and Amarillo, TX are usually classified as some of the windier cities. Chicago’s nickname, “The Windy City” has some political history to it (even though it does get quite breezy there).

Through the winter and spring, be sure to pay attention for wind alerts issued by your local National Weather Service office. These alerts are usually issued in the event of potential downed trees and power outages.

Aerosols and melting snow

By: Marina Kobasiuk

Snow has a varied life span across North America. In some regions after the first few snowfalls, the sight of it will be consistent through much of the winter, or the time period between snow melts will be larger. While other locations, especially coastal regions and cities, can see many melts and fresh covers of snow through the entire season. Long term climate certainly plays a part; average temperature and humidity affect how snow melts or sublimates, as does geography. These factors are important due to how easily snow can resist melting by reflecting the sun’s energy back into the atmosphere.

But what also affects how snow melts is the quality of the air that was involved when the precipitation formed. This is called snow darkening and it reduces the ability of snow to reflect radiation. Aerosols particles can be brought to the surface after snow has formed around them due to wet deposition, and then are part of the snowpack on the ground. If those particles can absorb the radiation from the sun, such as carbon rich ash for example, they encourage the melting of snow. So regions with heavy industry and pollution will see this effect more strongly from emissions much more than rural regions that are not as rich with these heavier particles, though this natural effect is not limited to pollution.

This cycle continues as once a patch of snow has melted sufficiently to reveal a much darker area of ground beneath it. Exposed to the sun this darker surface can absorb and emit radiation and also start to melt the snow around it and encourage the melting or evaporation of all the snow around such spots. So if you travel to a place with low pollution or lots of shade, you’ll likely see snow on the ground for much longer times through the winter, even as it melts away closer to larger populations!


Jacobson, Mark Zachary. Air Pollution and Global Warming: History, Science, and Solutions. 2nd ed., Cambridge University Press, 2012.

Arctic Blast!

Arctic Blast! by: Scott Doering

A Look Back at the Bitterly Cold End of December 1863 through the Early Part of January 1864

Arctic outbreaks are nothing news. The most significant recent Arctic outbreaks occurred a little over a year ago, from December 23rd, 2017 through January 5th, 2018. Bone-chilling temperatures gripped a good portion of the lower 48 states, from the Northern Rockies, south to Texas and even the deep-south. The Great Lakes and the East Coast were not spared by the cold. Several locations experienced one of their coldest late Decembers through early January period on record. Wind chill of 50 below to 60 degrees below zero was observed in the Dakotas and Minnesota on December 30th – January 1st. Mount Washington in New Hampshire recorded a temperature of -36° on the morning of January 6th. When combined with 92 mph winds, the wind chill was an astonishing -92°F!

The image above shows temperature ranking from December 23rd, 2017 through January 5th, 2018. Any location with a 1 means it was the coldest Dec 23 through Jan 5 on record. The image is from the Southeast Regional Climate Center’s Climate Perspectives, via

Was the cold at the end of December through the first part of January 2018 a surprise? Nope! Severe Arctic outbreaks like the one above are typically well forecast days in advance. Meteorologist and climatologist at the Climate Prediction Center analyze various climate signals, or oscillations when issuing their 6-10 Day and 8-14 Day Outlooks. 

The image above is the Climate Prediction Center’s 6-10 Day Outlook issued on December 23rd, 2017. The graphic is a forecast of temperature anomalies for December 29th, 2017 through January 2nd, 2018. The darker the purple, like over the eastern half of the lower 48, the higher the confidence for below average temperatures. Meteorologist today rely on weather models and observations to monitor incoming bone-chilling temperatures.  Wind chill advisories and warnings are issued, usually, 12 to 24 hours in advance, so people can be prepared before heading out. Today we have a wind chill graph which informs people how long they can stay outside before getting frostbite. Wind chills were introduced in the 1970s as a way to express the severity of the weather.  Back in 1863, weather forecasts were none existent. Arctic cold waves were brutal and caused significant hardship in early Americans. The weather was documented during this time period by meteorological observers for the Smithsonian Institution, Signal Service reports (Fort Data), and Civil War Diaries. A diary by Samuel A. Agnew in northeastern Mississippi wrote about the cold, saying “It is severely cold – as cold as it ever gets in this country…”

Beginning on December 31st, 1863, a horrific snowstorm with gale force winds, (39 to 54 mph) and extreme cold impacted the Midwest, from Iowa to Ohio. The significant blowing and drifting snow blocked highways and railroads, with some areas, like Galesburg, Illinois failing to receive mail from Chicago for a week. Elsewhere in Illinois, “500 head of sheep perished under snow-drifts in Menard County. All young pigs that were not very well protected died, either from the snow drifting or from the cold. Twenty five per cent of the sucking calves were lost. Many fat hogs, and partially so, were smothered beneath the snow or died from their piling – piling on top of each other.” Livestock across the Midwest perished due to massive snow drifts and the extreme cold.

Temperatures plunged 30 to 60 degrees in less than a day in some places. In Welshfield, OH, the temperature fell from 40° on December 31st at 10 pm, to -14° January 2. “The people being wholly unprepared for so sudden and so great a fall of temperatures, much damage was done.” Easton, OH fell 61° in 12 hours, and Urbana dropped 45° in just 10 hours. In Ottawa, Illinois, on January 1st, the weather was intensely cold. One man in this city froze to death but a short distance from his own house.  Also a man and his wife, and their span of horses, within two miles of this station perished.  The observer from Galesburg wrote, “Such a storm and such cold are seldom experienced here.” In St. Louis, “the thermometer sank to 26 degrees below zero on the night of 31st of December, and remained below zero for nearly two weeks.” Fruit trees heavily damaged by the prolonged cold. Raspberries and blackberry bushed not protected were severely injured.

The following information from the Arctic blast are from the meteorological observers for the Smithsonian Institution. The information was published in the Bi-Monthly Report of The Agricultural Department for January and February 1864. (Source) The reports were nearly quoted word for word.

Fond Du Lac County, Wisconsin, Jan 1st – “Wind north, extremely cold and blustering; snowed all night, and drifted all day; highways and railroad blockaded; thermometer 35 degrees below zero.” Fond Du Lac County, Wisconsin, Jan 2nd – “Wind northwest; thermometer 38 degrees below zero. The coldest day and hardest storm ever known in Wisconsin.” Jan 6th “measured the snow; found it 24.5 inches on level.”

Mr. John Hill of Petersburg, Menard County Illinois – “500 head of sheep perished under snow-drifts in Menard county. All young pigs that were not very well protected died, either from the snow drifting or from the cold. Twenty five per cent of the sucking calves were lost. Many fat hogs, and partially so, were smothered beneath the snow or died from their piling – piling on top of each other.”

Adams County, Iowa – “The coldest day was Jan 1st; thermometer 24.5 degrees below zero. During the first three days of January, the thermometer kept below zero all the time.”

St. Louis, Missouri – “January 1 – The thermometer sank to 26 degrees below zero on the night of 31st of December, and remained below zero for nearly two weeks. On the morning of 31st it was 16° above. Soon a snow-storm set in, and by three pm the thermometer indicated 10 degrees below zero, with a gale blowing from nearly due west. Stock has suffered severely. Horses, mules, cows and hogs, more or less, have perished in the storm. Our peach trees are killed to the ground. Nearly all our heart-cherries the same. Quinces, fully one half killed. Pear trees, much damage to tender varieties; young wood nearly all killed. Vineyards badly injured.”

New Castle, Indiana – “Thermometer at 2 pm, December 31, 35 degrees above zero. Thermometer at 5 am, January 1, 19 degrees below zero; a change of 58 degrees in 15 hours.”

The following communication was received and read before the Cincinnati Horticultural Society

Bardstown, Kentucky – “On the night of December 31 it turned suddenly cold; the thermometer suddenly sunk upwards of 50 degrees that night; and next morning at 8 it stood at 8 degrees below zero.”

Cynthiana, Kentucky – “On the 31st of December we had a very warm day, with moderate rain. That night within the space of 12 hours the thermometer fell 54 degrees, and during the 1st, and for two weeks continually, it was from 10 degrees below to 15 above.”

Additional reports from the Bi-Monthly Report from The Agricultural Department for March and April 1864. (Source)

South Hartford, New York – “January 1; the month commenced with a fine drizzling rain which continued until 2:30 pm; thermometer indicating 42°. At 7 am of the 2nd the temperature had fallen to zero, being a change of 42° in seventeen hours.”

Urbana, Ohio – December 31, a sudden and extreme change during the night. At 9 pm the thermometer 34°; At 7 am, January 1, the thermometer was down to 11 below zero.

Eaton, Ohio – December 31, “At 7 pm the mercury stood at 45°. It was not noticed at 9, but it much have been down nearly to zero. At 7 am, January 1, it stood -16°; being a change of 61°

Welshfield, Ohio – The temperature fell from 40°, December 31, at 10 pm to -14° January 2. The people being wholly unprepared for so sudden and so great a fall of temperatures, much damage was done.

South Bend, Indiana – “Seven inches of snow on the 31st of December. Temperature at 9 pm, 18°; fell thirty-eight degrees by 7 am next morning, January 1.”

Winnebago, Illinois – “December 30, sky cloudless till about 4 pm, when a low bank of clouds was observed along the southwestern horizon, which overspread the sky during the evening. December 31, a severe snow-storm set in soon after midnight and continued through the day. The snow ceased soon after nightfall. The wind continued blowing a gale through the night, with heavy drift and increasing cold. The day following (January 1) was one of the most severe on record in this latitude.”

Ottawa, Illinois – “January 1, weather intensely cold; one man in this city froze to death but a short distance from his own house; also a man and his wife, and their span of horses, within two miles of this station. Snow, of the 30th and 31st December and today one foot in depth. It is badly drifted, and the cars have stopped running.”

Galesburg, Illinois – “Very cold high wind night on December 31; snow in motion; cattle, horses, and hogs suffered greatly, and many froze. The roads were blocked up, and no mail was received from Chicago for a week. Such a storm and such cold are seldom experienced here.”

Sandwich, Illinois – “One of the most terrible snow-storms ever witnessed here, accompanied with severe cold, visited us at the close of the old year and the beginning of the new. It began the last day of December to storm moderately from the north; at 3 am, January 1, it began to increase in violence, and continued until it become impossible for man or beast to withstand its violence; a 7 am, January 1, the mercury marked -26°, and snow falling rapidly; railroads became blocked, and the Chicago, Burlington and Quincy road was so obstructed that for one week no mail express passed this (Sandwich) station. Many cattle perished in the corn fields; stock in transportation on the car perished by hundreds, and thousands of fowls froze upon their perches. The depth of snow falling here was about two and a half feet. The extreme cold continued about eight days. Peaches are destroyed, that is, the fruit germs, and in many instances the trees are ruined. The fruit germs upon nearly all early varieties are also destroyed. Early Richmond cherries also, and probably plums. Peaches are said to be destroyed more than a hundred miles south of Memphis.”

Pekin, Illinois – “December 31. I was up several times last night; the wind increased in force; the snow came faster each time I looked out; 4 pm, the wind is from northwest; it is so severe that I cannot at times walk against it without using all my strength. I do not remember ever experiencing so severe a snow-storm; it continued about the same to midnight. After 8 pm the wind was from the west.”

Augusta, Illinois – “December 31. From 9 pm last night to sunrise this morning, snow fell to the depth of about seven or eight inches, and it continued to snow, more or less, nearly all day; the wind blew very hard, and the snow drifted so much that it was very difficult to tell the average depth; it was a very severe storm; I remember but one equal to it since I have resided in Augusta, from 1833 to the present time.”

Waverly, Illinois – “A severe snow-storm began at 10 pm on the 30th December, and continued over the 31st, the wind blowing almost a gale some of the time from the northwest, with the thermometer almost at zero; about ten or twelve inches of snow fell, and it lays piled up in every conceivable shape. The thermometer -24° this morning, (January 1.) The storm must have obstructed railroads and killed much stock for farmers.”

Athens, Missouri – “This month of January is the coldest weather that has been experienced here for a number of years. From the 23rd of December to the 23rd of January the ground has been covered with snow to the depth of seventeen inches on a level, and drifted to the height of the fences. Many roads became impassable, the general depth of the drifts being six feet. We have had as deep snows before, but not so cold, not drifted so badly. The timber was loaded down with snow, and much of it broken, especially the pin oak and black jack, which had the leaves on. Great number of cattle, sheep, hogs, and fowl have perished, and many persons have been frozen to death. Twelve inches of snow fall on the 28th of December; none on the 29th or 30th, one inch on the 31st; one inch on the 1st of January.”

Fontenelle, Nebraska – “December 31 is the coldest and most disagreeable day experienced in this Territory by the oldest settlers. Ground frozen eight inches deep.”

Geneva, Wisconsin – “January 1, snow-drifts are from four to twelve feet high; roads running north and south are impassable. Large number of quails are found frozen in the snow.”

Beloit, Wisconsin – “The 1st day of January (mean temperature -25°) was the coldest day on this record for fourteen years, and the first week was five degrees colder than any week during that time, but the amount of snow was not so great as it has been. It was drifted terribly, and blocked the railroad trains for several days. I saw some drifts in a railroad cut east of here fourteen feet high.”

Algona, Iowa.—On the 30th December, at 9 pm, the wind began to drift the snow, which had fallen to the depth of five and a half inches on the26th and 27th, and continued to increase all night, and by daylight of the 31st it was blowing a hurricane, which continued all day and till New Year’s morn with the same violence apparently. At no time in the whole day could a house be seen at six rods’ distance. The extreme cold in the face of the wind was, at 7 am,—15°; at 10 a.m.,—17°; at 2 p.m.—20°; at 6 p.m.,—24° at 9 p. m., —26°. In some places there is no snow; at others it is ten feet deep, according to location, and considerable damage has been done by blowing down hay and straw stacks and timber. The early part of January was clear and no snow.

Mount Pleasant, Iowa.—“Thursday, December 31, has been the most stormy and dismal day that I have ever known in this latitude. The wind blew a gale all day from the northwest, and the driving snow rendered the air dark, and made it almost impossible to go about out of doors. More stock died on this night in Iowa than was ever before known in any month of time; cattle, sheep, and hogs were often buried in snow-banks, where they perished by being smothered, &c. One man, in this county, lost fourteen head of cattle.”

Muscatine, Iowa.—“December 31, the most severe day of the winter so far; a most powerful northwester with snow-squalls and the air full of snow; thermometer below zero all day. The storm began in the evening of December 30; some flying clouds appearing and the cold wind beginning to rise at 10 p. m.; snow-squalls began in the night and continued all day the 31st. On the 5th of January the mail got through from the east the first time for six days; many cattle have frozen because they had not good shelter. January 2.—To-day has been a very severe one; thermometer —26° in the morning, and the average of the day—14.3°; not windy, and the snow appears to be done drifting. Yesterday and the day before were the severest which have been seen here for ten years. Drifting snow has completely blocked the railroads and country roads. The snow is about eighteen inches deep in the woods, most of it damp, frozen hard, so it will drift no more. January 8.—The past week has been about as cold as any I ever experienced; thermometer averaging —10° for eight days in succession. About one hundred head of cattle and many hogs froze to death in this county on the night of December 31; but they were not properly sheltered. Sheep crowded into sheds, and the snow drifting upon them, they piled up, and some smothered, and others froze—Foster.”

Prospect Hill, Floyd County, Iowa.—“The steadiness of cold from the eve of December 30 to the morning of the 10th of January has not been equalled in seven years and two months, the period my register covers. There was no visible increase of snow here, in the woods, on the 31st of December; still, on the prairie, the position of the sun was not apparent, except faintly, at 9 a. m., on account of blowing snow.—James Coley”

Fort Madison, Iowa – “The last day of 1863 was the most severe storm we have had here since this country was settled, and the year 1864 was ushered in by said storm. The night before New Year’s day was the most particularly severe, with high wind from the northwest and drifting snow; some stock was frozen to death, and a number of chickens. Nine and a quarter inches of snow feel on the 27th of December; note fell again until the 2nd of January, when there was half an inch, and three and a half inches fell on the 4th.”

Iowa City, Iowa.—“On the last day of the year (mean temperature —21°) commenced the most violent snow storm known in this region of country; snowing all day and night, and wind blowing violently ail the time.”

Natchez, Mississippi, on December 31st – “The morning was sultry and close; thermometer 80°; wind south; cloudy. About 9 am a remarkable change occurred, and the wind increased and became chilly, and then stinging cold, with occasional warmer gusts. What was remarkable this cold wind blew strongly directly up the river, or from a point south 30° west. At 12 pm the ground began to freeze and the wind had veered round to west. At 7 pm the thermometer stood at 23°, and next morning at 10°, and in some localities in the country as low as 8° above zero. The cold lasted till about the 10th of January.”

John Dalton

John Dalton – Meteorologist in History; Written by: Jenna Hans

Many of us know John Dalton for his Law of Partial Pressures, or maybe his work with the blind. Dalton is responsible for introducing atomic theory and the idea that everything is made up of little particles (atoms), and he even put together the first chart of atomic weights! However, what people might not know is that he was an active meteorologist, weather enthusiast, and that meteorology led Dalton to a lot of these theories and conclusions.

Growing up near the Lake District in northwest England, young John Dalton was among one of the most beautiful and mountainous regions in the UK, making it a great place for him to make meteorological observations. He used various instruments to take measurements of things like temperature, pressure, air circulation, and cloud formation. These measurements along with his observations were recorded in his book Meteorological Observations and Essays that was published in 1793. The book contains more than 200,00 entries, many of which we use in meteorological and climate records today2. In the book he also included guides for students, his thoughts on the composition of the atmosphere, and experiments he conducted.

Throughout the book Dalton outlines many different theories and conclusions he made through his observations, experimentation and research. This led him to publish ground breaking papers on evaporation and its role in the hydrological cycle. He made the statement that rain and dew are equal to the amount of water evaporated, something that was questioned at the time. Not only that, but he developed the evaporation equation (E=K(es-ea)) that is still used today3. He developed his law of partial pressures from atmospheric observations and even developed his 5-part atomic theory from his interest in atmospheric gasses1.For over 50 years Dalton went out to record his weather observations and even made entries from the day before his death in Manchester in 18443. Although his work was barely discussed, he continued to publish papers and books relating to meteorology and chemistry many of which have has stood the tests of time, proving his work to be accurate and ground breaking3. The amazing things that Dalton accomplished prove the importance of studying the natural world and how maybe us weather fanatics and storm chasers have a method to our madness!

  1. Christopher S.W. Koehler, The Atom Man, Chemistry Chronicles, 2003, 51-53
  2. John Dalton: Atoms, Weather, and Vision, SciHistory, 2012
  3. Howard and Sylvia Oliver, Meteorologists Profile-John Dalton, Weather Vol. 58,2003, 206-211