May 2019: Second Wettest Month on Record for US

When it rains, it pours! This old adage was proven to be true last month. With national weather data dating back to 1895, May 2019 was the second wettest month ever recorded in the contiguous United States. Only May 2015 was wetter.

According to NOAA, an average of 4.41 inches of rain fell across the lower 48 states, which is 1.50 inches above average. Heavy precipitation was reported from the West Coast through the Mid-West, and into parts of the Northeast. Kansas, Nebraska, and Missouri each experienced their wettest May on record.

This relentless rain caused deadly and destructive flooding in several states along the Arkansas, Missouri, and Mississippi Rivers.

While there were a number of factors that contributed to May’s excessive rainfall, including El Nino, climate change also likely played a part.  As the National Climate Assessment points out, heavy precipitation events are increasing in both frequency and intensity across the United States as the atmosphere warms.

As greenhouse gases heat the atmosphere, the air is able to hold more water vapor. More specifically, according to the Clausius–Clapeyron relation, for every increase of 1°F, the saturation level of the atmosphere increases by about 4%. In other words, warmer temperatures lead to more evaporation from oceans, rivers, and lakes, and therefore more water vapor is available to condense and fall as precipitation.

Sadly, with our global temperature continuing to rise, experts say we should expect to see more extreme rain and flooding events in the future.

Credit: NOAA

Names for the 2019 Atlantic Hurricane Season

Today is the first day of the 2019 Atlantic Hurricane Season. Although one named storm, Andrea, already formed, the season officially runs from June 1 to November 30.

Since 1950, each tropical storm or hurricane to form in the Atlantic has been given a unique name. They come from a set of six rotating lists produced by the World Meteorological Organization. A name is retired only when a storm was particularly noteworthy – causing a large number of fatalities or an extraordinary amount of damage.

Some notable retired names include:  Harvey, Irma, Katrina, Maria, Michael, and Sandy. The names for this year’s storms are listed below.

Credit: NOAA

The 2019 Atlantic Hurricane Season Outlook

The number of hurricanes that develop in the Atlantic basin varies from year to year. For 2019, NOAA’s Climate Prediction Center is forecasting a near average season.

Tropical cyclones, known as hurricanes in the United States, develop around the globe at different times of the year. In this country, we are most impacted by the Atlantic hurricane season, which affects the North Atlantic Ocean, Caribbean Sea, and the Gulf of Mexico. It runs from June 1 through November 30.

Overall, NOAA predicts a 70% likelihood of nine to fifteen named storms forming this season, of which four to eight could become hurricanes, including two to four major hurricanes. An average season produces twelve named storms, including six hurricanes and three that become major hurricanes.

A major hurricane is one that is rated category 3 or higher on the Saffir-Simpson scale.

This year’s outlook, according to NOAA, reflects several competing factors. On one side, there are above average sea surface temperatures in the tropical Atlantic to fuel any storms that develop. Additionally, there is an enhanced west African monsoon in place that can initiate disturbances that turn into storms over the Atlantic. On the other hand, there is an ongoing El Niño event. El Niño conditions in the Pacific tend to cause increased wind shear in the Atlantic, which suppresses tropical development in that basin.

Last year, 2018, saw a very destructive hurricane season in the Atlantic. It produced fifteen named storms, including, Florence and Michael.

Regardless of the number of storms that actually form this year, it is important to remember that it only takes one land-falling system to make it an impactful season.

Spring is Heating Up

Spring is a transitional season. It is a time when the chill of winter fades away and the warmth of summer gradually returns. But, as our climate changes, the season is heating up.

Across the contiguous United States, spring temperatures have increased an average of more than 2°F over the past fifty years, according to Climate Central. The southwest part of the country has seen the fastest seasonal increase, with Las Vegas, NV and Tucson, AZ warming more than 6°F since 1970.

Warming temperatures mean more frost-free days. While this may lengthen the growing season for some crops, it also extends the allergy season and allows pests like mosquitos and ticks to live and thrive longer.

Looking ahead, if greenhouse gas emissions continue to rise, scientists say spring could arrive at least two weeks earlier by 2050 compared to recent years.

After Review Hurricane Michael Upgraded to Rare Category-5 Status

Hurricane Michael, which pummeled the Florida panhandle in October, has been upgraded from a category-4 to a category-5 storm, the strongest on the Saffir-Simpson scale.

According to a report by the National Hurricane Center, the storm’s winds reached 160mph when it made landfall near Mexico Beach, FL. That is a 5mph increase from the estimate used last autumn. The agency says the uptick was the result of a re-analysis of reams of data, including aircraft winds, surface winds, surface pressures, satellite intensity estimates, and Doppler radar velocities.  The review also took into account data that was not available in real time.

In the grand scheme of things, an increase of 5mph may not sounds like a lot, but it puts Michael in rare company. It now ranks as the fourth category-5 storm on record to make landfall in the US. The other three were the Labor Day Hurricane of 1935, Hurricane Camille in 1969, and Hurricane Andrew in 1992. Michael is also the third cat-5 storm to hit the Sunshine state.

Regardless of the technical upgrade and historic statistics, Hurricane Michael was a devastating storm that will be long remembered by those it affected. The storm claimed the lives of 16 people and caused an estimated $25 billion in damage. More than six months after coming ashore, much of the area is still recovering.

Hurricane Michael making landfall as a Category 5 storm along the Florida Panhandle on October 10, 2018. Credit: NOAA

Hurricane Names Florence and Michael Retired by WMO

There will never be another hurricane by the name of Florence or Michael. The World Meteorological Organization (WMO) has announced that it is officially retiring these names from its list of Atlantic cyclones.

The WMO is responsible for naming tropical storms and hurricanes around the world.  It maintains a set of six rotating lists for each hurricane-prone region. After a six-year cycle, names are re-used.  Names are only retired when a storm was particularly noteworthy – causing a large number of fatalities or an extraordinary amount of damage.

Hurricane Florence. Credit: NOAA

The 2018 Atlantic Hurricane Season was active, but two storms were particularly destructive. Hurricane Florence made landfall in North Carolina in September as a cat-1 storm and dumped a massive amount of rain on the area. Traveling inland, it caused catastrophic flooding in parts of both North and South Carolina. In Elizabethtown, NC, 35.93 inches of rain was reported, making it the wettest tropical cyclone on record for the state. For the contiguous US, it ranked as the eighth wettest.

Hurricane Michael. Credit: NOAA

In October, Hurricane Michael hit the Florida panhandle as a cat-4 storm. With winds measured up to 155mph, it was the strongest storm on record to strike the region and the third strongest storm to make landfall in the continental US. Its powerful winds and storm surge flooding decimated the Panama City area.

To date, according to the National Hurricane Center, 89 storm names have been retired since the current naming system began in 1953. The 2005 hurricane season holds the record for the most retired names – five – in one season.

Starting in 2024, when last year’s list is recycled, the names Florence and Michael will be replaced by Francine and Milton.

The 2019 Atlantic hurricane season officially begins on June 1.

Speaking About Art, Climate, and Environmental Policy at AMS

The 99th Annual Meeting of the American Meteorological Society is taking place this week in Phoenix, Arizona. Its theme is “Understanding and Building Resilience to Extreme Events by Being Interdisciplinary, International, and Inclusive.”

Thrilled to be a part of it, I will be giving a presentation titled “The Power of Perception: Art, Climate, and the History of US Environmental Policy”. The talk looks at the role art has played in helping to build the political will behind several landmark environmental policies over the years and how it can help with climate change communication today.

From the Yosemite Land Grant of 1864 to the present, images have helped give the public, and the policy makers they elected, a new way to relate to and understand the issues of their time. In many cases, images mobilized public concern that helped drive legislation. The publication of photos of the Cuyahoga River fire of 1969 in Time Magazine, for example, helped spur the passage of the Clean Water Act and the creation of the EPA in the 1970s.

The talk also highlights the way technology has changed the way we relate to images and the role movies – the art of moving images – can play in reaching a wide and diverse audience.

Credit: AMS

The Snowiest Places in the US

Snow is a common occurrence during the winter months for many parts of the US. But, some places tend to get more than others. In fact, there are locations that see triple digit snow totals every year.

In the east, the Great Lakes region is well known for lake effect snow events. With moisture laden snow bands forming down-wind of the massive lakes, it is not uncommon for some communities to see more than 100 inches of snow each season.  For example, Syracuse, NY, on average, gets 123.8 inches of snow annually.

In the west, even more snow is par for the course in the Cascade Range of Washington state. The Paradise Ranger Station in Mount Rainier National Park holds the record for the greatest average annual snowfall in the US. At 5400 feet in elevation, they see 643 inches of snow (53.6 feet) each year.

Storm systems that move in from the Gulf of Alaska run into the Cascade Mountains and are forced upward. As they rise, the moisture in the air cools, condenses, and falls as precipitation. At lower elevations, it comes out as rain, but at higher elevations, where the air is colder, it falls as snow. Standing at 14,410 feet above sea level, Mount Rainier is the highest peak in the Cascades.

Mount Rainer National Park sees the highest average annual snowfall in the US. Credit: Hemmings

Fourth National Climate Assessment: A Dire Forecast for US if Action is Not Taken

The Fourth National Climate Assessment (NCA4) report was released rather inauspiciously last week on the day after Thanksgiving – a traditionally slow news day. Nevertheless, the report is out and it clearly states, “the evidence of human-caused climate change is overwhelming and continues to strengthen.”

The massive report, considered volume two of NCA4, builds on the Climate Science Special Report issued last year. It gives a detailed account of what the impacts will be across the country and how the worst effects could be avoided.

The U.S average temperature, according to the report, has increased by 1.8°F since 1901, and is projected to continue rising. Over the next few decades, temperatures are projected to rise another 2.5°F.  By the end of the century, our average temperature could soar by as much as 11.9°F if greenhouse gas emissions continue to increase unchecked.

The report also looks at the long-term economic impacts for the country as the average temperature continues to climb. Costs from rising sea levels could reach as high as $118 billion and the projected total for damaged infrastructure is $32 billion. This is in addition to the reduced agricultural productivity expected from high heat and extended drought events. Overall, the report warns that if significant steps are not taken, climate change could slash the US economy’s GDP by 10% by the end of the century.

Not all doom and gloom, the report’s authors emphasize, “These impacts are projected to intensify—but how much they intensify will depend on actions taken to reduce global greenhouse gas emissions and to adapt to the risks from climate change now and in the coming decades.”

While similar in theme to the IPCC report from the UN, this assessment focuses solely on the United States. Emphasizing the fact that rising temperatures will affect different parts of our vast country in different ways, the NCA breaks the nation down into specific regions. It details the current and future impacts of climate change in each one:

The report also includes a supplemental set of State Climate Summaries that give a clear idea of what to expect in each of the 50 states as well as the US territories.

Mandated by Congress under the Global Change Research Act, this exhaustive 1600 page peer-reviewed report was produced by 300 scientists from 13 different government agencies. Published every four years, it is considered this country’s most authoritative statement on climate change.

Annual average temperatures across the United States are projected to increase over this century, with greater changes at higher latitudes as compared to lower latitudes, and greater changes under a higher scenario (RCP8.5; right) than under a lower one (RCP4.5; left). This figure shows projected differences in annual average temperatures for mid-century (2036–2065; top) and end of century (2071–2100; bottom) relative to the near present (1986–2015). Image credit: Fourth NCA, Vol II, figure 2.4.

Hurricane Michael Devastates Florida Panhandle

Hurricane Michael, the 13th named storm of this Atlantic Hurricane season, made landfall near Mexico Beach, Florida on Wednesday. It was the strongest storm on record to hit the Florida Panhandle.

Coming ashore with sustained winds measured up to 155mph, Michael was classified as a high-end category-four hurricane. Its powerful winds sheared roofs off buildings, uprooted trees, and toppled power lines. Storm surge flooding was also a major force of destruction. The NHC estimates the water reached between nine and fourteen feet above normally dry ground from Mexico Beach eastward through Apalachee Bay.

Fueled by the unseasonably warm waters of the Gulf of Mexico, Michael intensified rapidly as it moved closer to shore. According the NWS, Michael was the strongest hurricane to make landfall in the US since Hurricane Andrew in 1992. It was also the strongest storm to ever hit this country in the month of October.

Moving quickly, the storm traveled across the Florida Panhandle toward the northeast. Its strong winds and heavy rain caused flashing flowing and power outages in several states.

As of Friday, the death toll from this historic storm stands at sixteen. But sadly, officials say that number is expected to rise as search and rescue efforts continue in the hardest hit areas.

Hurricane Michael makes landfall near Mexico Beach, FL. Credit: NOAA