By Miriam Raftery
January 8, 2013 (Washington D.C.) – If the weather seemed hotter last year than in the past, your memory is correct.
In its State of the Climate Report, the National Oceanic and Atmospheric Administration’s National Climatic Data Center reveals today that 2012 averaged the hottest temperatures ever recorded for the lower 48 states in the U.S. Nationwide, the average temperature for 2012 was 55.3 degrees Fahrenheit—a full 3.2 degrees higher than the 20th Century average and one degree hotter than the previous hottest year on record (1998).
It was also a historic year for extreme weather that included severe drought, larger wildfires, hurricanes and storms--the second worst year on record.
View report: http://www.ncdc.noaa.gov/sotc/ and scroll down for highlights.
The average precipitation total for the contiguous U.S. for 2012 was 26.57 inches, 2.57 inches below average, making it the 15th driest year on record for the nation. At its peak in July, the drought of 2012 engulfed 61 percent of the nation. The dry conditions proved ideal for wildfires in the West, charring 9.2 million acres — the third highest on record.
Significant weather and climate events
2012 included 11 disasters that have reached the $1 billion threshold in losses, including Hurricanes Sandy and Isaac, as well as tornado outbreaks experienced in the Great Plains, Texas and Southeast/Ohio Valley. Note: The Annual Climate Report for the United States has several pages of supplemental information and data regarding some of the exceptional events 2012.
Every state in the contiguous U.S. had an above-average annual temperature for 2012. Nineteen states had a record warm year and an additional 26 states had one of their 10 warmest.
Winter warmth limited snow with many locations experiencing near-record low snowfall totals. The winter snow cover for the contiguous U.S. was the third smallest on record and snowpack totals across the Central and Southern Rockies were less than half of normal.
The warm spring resulted in an early start to the 2012 growing season in many places, which increased the loss of water from the soil earlier than what is typical. In combination with the lack of winter snow and residual dryness from 2011, the record warm spring laid the foundation for the widespread drought conditions in large areas of the U.S. during 2012.
The above-average temperatures of spring continued into summer. The national-scale heat peaked in July with an average temperature of 76.9°F, 3.6°F above average, making it the hottest month ever observed for the contiguous United States. An estimated 99.1 million people experienced 10 or more days of summer temperatures greater than 100°F, nearly one-third of the nation’s population.
Autumn warmth in the western U.S. offset cooler temperatures in the eastern half of the country. Although the last four months of 2012 did not bring the same unusual warmth as the first 8 months of the year, the September through December temperatures were warm enough for 2012 to remain the record warmest year by a wide margin.
The nationally-averaged precipitation total of 26.57 inches was 2.57 inches below average and the 15th driest year on record for the lower 48. This was also the driest year for the nation since 1988 when 25.25 inches of precipitation was observed. Each season of 2012 had precipitation totals below the 20th century average.
The wildfire activity of 2012 supplanted 2011's rank as third most acres burned, behind the 2006 and 2007 seasons. Although the number of fires was below-average, the size of the fires was notably increased. The annual fire size of 137.1 acres was the most since 2000 for any January through December period, which was about 1.5 times the 10-year average (based on 2001-2010).
The State of the Climate Report is a collection of monthly summaries recapping climate-related occurrences on both a global and national scale. The report is composed of the following sections:
- Global Analysis — a summary of global temperatures and precipitation, placing the data into a historical perspective
- Upper Air — tropospheric and stratospheric temperatures, with data placed into historical perspective
- Global Snow & Ice — a global view of snow and ice, placing the data into a historical perspective
- Global Hazards — weather-related hazards and disasters around the world
- El Niño/Southern Oscillation Analysis — atmospheric and oceanic conditions related to ENSO
- National Overview — a summary of national and regional temperatures and precipitation, placing the data into a historical perspective
- Drought — drought in the U.S.
- Wildfires — a summary of wildland fires in the U.S. and related weather and climate conditions
- Hurricanes & Tropical Storms — hurricanes and tropical storms that affect the U.S. and its territories
- National Snow & Ice — snow and ice in the U.S.
- Tornadoes — a summary of tornadic activity in the U.S.
- Synoptic Discussion — a summary of synoptic activity in the U.S.