Our team of meteorologists rank the top five weather events of 2015 in North America.
5) Strong El Nino
Weather headlines across the globe in the second half of 2015 were dominated by a steadily intensifying El Nino, the abnormal pooling of warm water off the Pacific coast of northern South America. Water temperatures have been running an astounding 3-4°C above normal there, leading to values of the ONI (Oceanic Nino Index, one of several standard measures of El Nino intensity) that place this event in the top three strongest El Ninos of all time, alongside the notoriously stormy winters of 1982-83 and 1997-98. While El Nino can wreak havoc on weather patterns around the world, some of the impacts can actually be beneficial. For instance, the Atlantic hurricane season was unusually quiet thanks to El Nino, pushing the streak of seasons without a strike on the US mainland from a major hurricane past a decade. There is also hope for some drought relief in California.
4) Christmas Tornado Outbreak & Flooding
Prior to December 23, 2015 was on track to set the record for the least number of tornado-related fatalities, with 10 deaths through mid-December. The last time fatalities were this low was in 1910 when there were 12 fatalities. Unfortunately, the holiday season was accompanied by a powerful storm that produced deadly tornadoes that claimed the lives of 24 people in Texas, Mississippi and Tennessee. The same monster storm also produced flooding rains and blizzard conditions across the central United States that killed at least another 19 people. All of the water that fell in the multi-day storm is now flowing into rivers and streams, leading to historic wintertime flooding in the Mississippi River watershed.
3) Record snow in the Northeast
Boston stole headlines early in the year as the city broke records with the snowiest season on record. A total of 111” of snow fell in Boston, surpassing the previous record of 108” set back in the winter of 1995-1996. Numerous snow storms hit the Northeast region this past winter, leading to more broken records in other cities such as Worcester, Massachusetts which saw 120” of snow, and Providence, Rhode Island, which saw 76”. The most notable winter storm occurred on January 26 and 27 when a nor’easter brought over 30” of snow to many parts of Massachusetts. Numerous states such as New York, New Jersey, Connecticut, Rhode Island and Massachusetts declared states of emergency, shutting down major roads and public transportation.
2) Hurricane Patricia
On October 23, 2015, Hurricane Patricia made landfall in Cuixmala, Jalisco. Prior to landfall, Patricia reached peak sustained winds of 200 mph, making it the strongest hurricane ever recorded in the western hemisphere. Although the storm weakened before landfall, flooding from the hurricane still caused roughly $400 million in damages. The warm waters associated with El Nino helped fuel Patricia as well as dozens of other tropical cyclones in the eastern and central Pacific in 2015. In August, an unprecedented three tropical cyclones of category 4 intensity occurred simultaneously in the central Pacific Ocean.
1) Record Flooding in the Southern Plains and Southeast
The middle of spring 2015 gave meteorologists their first inkling of El Nino’s impacts on the weather in the U.S. Strong winds aloft aided in the transportation of rich moisture from the abnormally warm waters of the tropical Pacific to the southern U.S., a pattern that would continue most of the year.
The states of Texas and Oklahoma had their wettest month of May ever on record, which quickly ended a drought that had been ravaging those states since 2011. Further east in South Carolina, torrential rain fell in October, leading to catastrophic flash and river flooding, so much that it was considered a 1,000-year flood. Unfortunately, the flooding was both deadly and destructive. Scores of people were killed by high waters, and damage estimates were upwards of $3 billion in Texas and Oklahoma and $2 billion in South Carolina.