Record flooding, drought part of range of weather extremes in US this summer

The National Oceanic and Atmospheric Administration has released its 2022 Summer Climate Report, which outlines the extreme weather events from June to August in the U.S.

The report also describes where this year ranked compared to previous summers, using data from dozens of weather stations in each state.

US record temperatures

The summer of 2022 ranks third-warmest on record, with an average temperature across the contiguous United States at 73.9 degrees, according to the report. That’s 2.5 degrees above average, coming in only 0.01 degrees behind 1936 (when the dust bowl was in full swing) for the No. 2 spot. The hottest summer on record was in 2021.

It wasn’t just the highs that were sweltering, it was often the lows. The average minimum temperature across the country hit a record of 62.3 degrees this August, meaning there wasn’t much relief during the overnight hours. Houston broke several records for warmest low temperature, only bottoming out at 86 degrees after reaching highs above 100 degrees on multiple occasions. Without any cooler temperatures at night, the cumulative heat can be dangerous.

Heat is the No. 1 weather-related cause of death each year, and communities have recently taken it more seriously by opening cooling shelters to those most at-risk during heat waves.

Rainfall

While some parts of the country suffered from serious to exceptional drought, others dealt with major flooding. Taking the whole country into account, the precipitation turned out average, but how much rain you saw heavily depended on which region you were in. For example, Arizona had its seventh wettest summer, while Nebraska came in at third driest, according to NOAA.

Monsoon season in the Southwest is a typical occurrence during the summer months, but it started earlier than normal this year and brought flash floods to highly populated areas at times. Las Vegas experienced major flooding across the city in late July and again in early August, flooding casinos and leaving two dead.

August also brought a relentless surge of rainfall to northern Louisiana and Mississippi.

The several-day deluge caused major flash flooding in Jackson, Mississippi, where cars were submerged and people were left standing on their roofs waiting for rescue. More than 153,000 residents didn’t have clean drinking water for weeks after the water treatment facility went offline in the flood.

1,000-year floods

A 1,000-year rainfall event means that there is a 1 in 1,000 chance that a flood of that magnitude will occur in any given year. Three such events happened in August.

On Aug. 2, southern Illinois picked up a foot of rain in only 12 hours. Near Newtown, Illinois, an incredible 14 inches fell in those 12 hours, according to the National Weather Service.

Death Valley isn’t known for its rainfall, but on Aug. 5, the National Park was drenched with 1.70 inches of rain, leading to damaging flooding and trapped visitors. That rainfall broke a record that had stood for more than 34 years.

Then, on the morning of Aug. 22, the rain began in Dallas and didn’t stop. Hefty downpours led to catastrophic flooding across the city, with many nearby towns recording more than a foot of rainfall.

The governor declared a disaster for 23 counties in Texas due to the rainfall. Although it was destructive for many, it was bittersweet because it helped alleviate the exceptional drought that plagued that area for months. Water reservoirs rose significantly after being at record low levels just a week before, and the U.S. Drought Monitor noted major improvement in its update following the flood event.

Drought

Even though there were several drought-busting rain events across the country, the U.S. finished up the summer with 45.5% of its land mass in drought conditions, the NOAA report said.

The northeast was one region that saw the drought ramp up during the summer months. Lawns that were a healthy shade of green in May were crunchy and yellow by August, as the rain stayed away for weeks. As a result, Massachusetts saw extreme drought spread across the eastern half of the state, and severe drought expanded to Rhode Island, Connecticut and New York, according to the U.S. Drought Monitor.

Meanwhile, the intense drought set the stage for a supercharged wildfire season in the west. Gusty winds helped easily spread these fires that had no resistance from the weather.

Tropics

In the tropical Atlantic, there was only one word to describe the situation: quiet. From July 3 to Sept. 1, there were no named storms in the Atlantic basin. That stretch of 60 days was the longest stormless stretch since 1941, according to the National Hurricane Center.

In September, the tropics began to heat up. Several named storms formed right around the historical peak of hurricane season in the Atlantic. The strongest of which was Hurricane Fiona, which peaked as a Category 4 storm after dropping catastrophic rainfall on Puerto Rico.

Roasting in Europe

Across the pond, records were just as prevalent as they were in America this summer. Europe experienced its hottest summer on record, with several countries roasting in a mid-summer heat wave that shattered long-standing records. It peaked on July 19, when dozens of weather stations across the U.K. topped 100 degrees. London soared to an incredible 104 degrees that day, according to the U.K. Met Office.

Around the world

Globally, the June-August period tied for the fifth warmest in the 143 years of records.

"The five warmest June-August periods on record have occurred since 2015," according to NOAA,

Both hemispheres came in above average, and while June-August is winter in the Southern Hemisphere, temperatures were not nearly as cold as they typically are. Antarctic sea ice during that time frame ended up at record low levels, according to climate scientists at NOAA’s Geophysical Fluid Dynamics Lab.

In terms of rain, Pakistan dealt with some of the worst floods in recent history. Extreme monsoon rainfall in August is estimated to have killed more than 1,500 people and destroyed more than 1.7 million homes.

Connection to climate change

While not every weather event can be attributed to climate change, some are undoubtedly enhanced by our warming world, as explained in the Intergovernmental Panel on Climate Change 2022 Assessment.

An example of this is the extreme flooding rain events. With ocean temperatures significantly higher than average, there is more moisture in the air due to evaporation. Also, higher temperatures can hold more water content, so the likelihood of heavy rain events rises with the temperature.