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April showers and cool temperatures brought drought relief to many areas across the United States. Drought improved for parts of the Plains and Southeast, but worsened in the Southwest. According to the latest statistics from NOAA’s National Climatic Data Center, the percent of the contiguous United States experiencing moderate-to-exceptional drought dropped from 52 percent at the beginning of the month to less than 47 percent at the end.

The maps above show the temperature in April 2013 compared to the 1981–2010 average (top) and the percent of average precipitation (bottom) across the United States. On the temperature map, shades of red indicate temperatures up to 8° Fahrenheit warmer than average, and shades of blue indicate temperatures up to 8° Fahrenheit cooler than average. The darker the color, the greater the difference from average. On the precipitation map, brown areas received less than 100 percent of their average April precipitation, and green areas received more than 100 percent of average.

As the band of blue across the center of the country on the temperature map indicates, the central United States was much cooler than average during April. North Dakota had its coldest April on record, with a statewide average nearly 10° Fahrenheit below the 20th-century average. Six additional states—South Dakota, Nebraska, Kansas, Oklahoma, Minnesota, and Wisconsin—each had average April temperatures that ranked among their top ten coldest. However, the East Coast and parts of the West saw near and above-average temperatures during the month. For the lower 48 as a whole, the average April temperature was 49.7° Fahrenheit, making it the coolest April since 1997.

Along with these cool temperatures, the Northeast, Midwest, and the Southeast were wetter than average during April. Iowa and Michigan both had their wettest April on record, and Tennessee, Illinois, Indiana, and Wisconsin each had a top ten wet April. These wet conditions across the central United States resulted in several rivers in Illinois, Iowa, and Michigan reaching record high levels. The Mississippi River at St. Louis also reached flood stage after dropping to near-record low levels at the beginning of the year.

While April lived up to its wet reputation in some regions, the Southwest saw below-average precipitation during the month exacerbating the drought already in place in those regions. New Mexico had its 12th driest April on record, and California had its driest January to April on record. Water surveyors reported only 18 percent of normal snowpack in the Sierra Nevada Mountains. On top of the continuing drought, this is bad news for California, which depends on a steady stream of snowmelt to replenish reservoirs throughout the summer.

Caption by Susan Osborne, Caitlyn Kennedy, and Jake Crouch, adapted from the April 2013 National Climate Report from the National Climatic Data Center (NCDC). Maps by NOAA Climate.gov team, based on U.S. Climate Division data from the NCDC. Reviewed by Jake Crouch, National Climatic Data Center.

While Mother Nature was still giving the United States the cold shoulder during March, many other areas across the world experienced higher-than-average monthly temperatures according to the latest statistics from NOAA’s National Climatic Data Center. The average global temperature for March 2013 tied with 2006 as the 10th warmest March since recordkeeping began in 1880. It also marked the 37th consecutive March and 337th consecutive month with a global temperature above the 20th century average. The last below-average March temperature was March 1976, and the last below-average temperature for any month was February 1985.

The map above shows temperatures relative to average across the globe for March 2013. Shades of red indicate temperatures up to 11° Fahrenheit warmer than the 1981–2010 average, and shades of blue indicate temperatures up to 11° Fahrenheit cooler than the average. As the red-shaded regions demonstrate, most of Africa and much of Asia experienced above-average March temperatures. Far northeastern Canada, part of western Greenland, and sections of central Asia observed temperatures that were at least 9° Fahrenheit above average.

The March nationally averaged maximum temperature across Australia was 1.18° Fahrenheit above the 1961–1990 average. This was the eighth consecutive month, since August 2012, that every state and territory across the country had an above-average monthly maximum temperature. Additionally, China observed its second warmest March since records began in 1961. The provinces of Chongqing, Gansu, Guangxi, Guizhou, Hunan, Jiangxi, Ningxia, Qinghai, Shanxi, Shaanxi, Sichuan, Xinjiang, and Yunnan all reported record warmth for the month.

Meanwhile, most of Europe, northern Asia, central and western Canada, the central and eastern United States, and southern South America were notably cooler than average as the blue-shaded regions demonstrate. Parts of northeastern Europe and western Russia observed temperatures that were at least 9° Fahrenheit below average. The United Kingdom had its coolest March since 1962 and its coolest month overall since December 2010, with a March temperature 5.9° Fahrenheit below average.

In the video below, NCDC scientist Deke Arndt talks about climate variability and pockets of cold temperatures in a globally warmer world.

Map by Dan Pisut, NOAA Environmental Visualization Lab. Caption by Jessica Blunden and Susan Osborne. Adapted from the March 2013 Global Climate Report from NOAA’s National Climatic Data Center (NCDC). Reviewed by Jessica Blunden, NCDC.

large temperature maps: March 2013 | March 2012
not shown: March 2013 percent of average precipitation

Looking at the temperature maps for March 2013, you might think that Old Man Winter over stayed his welcome or that Mother Nature was trying to make up for last March’s record-breaking heat. Much of the country felt spring would never arrive! All kidding aside, the maps above show the reality of the March 2013 temperature statistics, recently released by NOAA’s National Climatic Data Center.

These maps show where the March 2013 (top) and March 2012 (bottom) temperatures were different from the 1981–2010 average. The shades of red indicate temperatures up to 8° Fahrenheit warmer than average, and the shades of blue indicate temperatures up to 8° Fahrenheit cooler than average. The darker the color, the larger the difference from average.

As the March 2012 temperature map indicates, record- and near-record-breaking temperatures dominated the United States during the month. Every state in the nation experienced at least one record warm daily temperature during the month, and over 15,000 warm temperature records were broken. There were even several instances of the nighttime temperatures being as warm, or even warmer, than existing record daytime temperatures.

March 2013 was a stark contrast, as many of those same locations with record-breaking warmth in March 2012 saw temperatures below average during the month. The average temperature for the contiguous United States during March was 40.8° Fahrenheit, nearly 1° Fahrenheit below the twentieth-century average and the 43rd coolest March on record.

Most of the eastern United States was cooler than average during March 2013, with the exception of New England. Eleven states in the Ohio Valley, along the Gulf Coast, and in the Southeast had March temperatures that were among their ten coolest. In fact, Alabama, Florida, Georgia, North Carolina, and South Carolina had March 2013 temperatures that were even cooler than those of January 2013.

Despite the cool temperatures that covered most of country in March 2013, temperatures were above average for parts of the West. Arizona, California, and Nevada each had March temperatures ranking among their ten warmest. Above-average temperatures were also observed in Washington, Oregon, Idaho, Utah, and New Mexico. Overall, however, the nationwide picture couldn’t be more different than that of March 2012.

In the video below, Deke Arndt of NOAA’s National Climatic Data Center talks about how opposite phases of a natural climate pattern known as the Arctic Oscillation likely influenced the dramatic contrast between temperatures in March 2012 and 2013.

These climate statistics and many others are part of NOAA’s National Monthly Climate Report. The National Climatic Data Center produces these monthly climate reports as part of the suite of climate services that NOAA provides government, business, and community leaders so they can make informed decisions.

Caption by Susan Osborne and Jake Crouch, adapted from the January 2013 National Climate Report from the National Climatic Data Center (NCDC). Maps by NOAA Climate.gov team, based on U.S. Climate Division data from the NCDC. Reviewed by Jake Crouch, National Climatic Data Center.

The contiguous United States experienced a warmer- and wetter-than-average 2012–13 winter according to the latest statistics from NOAA’s National Climatic Data Center. The December 2012–February 2013 total precipitation of 7.10 inches and this was 0.63 inches above the long-term average. Several winter storms passed through the country in February, improving drought conditions across the Southeast and Midwest, but lighter precipitation totals across the Central Plains and Mountain West provided little drought relief in those locations.

The maps above show the drought conditions at the beginning (left) and end (right) of winter, and the percent of average precipitation from December to February (above). On the precipitation map, shades of brown indicate areas that received less than 100 percent of their average precipitation and shades of green indicate areas that received more than 100 percent of their average precipitation for the month.

Winter was warmer than average for all states east of the Rockies, with the largest temperature departures from average along the East Coast. These above-average temperatures were, however, accompanied by above-average precipitation for most states east of the Rockies improving drought conditions in those areas, a contrast to the conditions of previous months. Many states in the Great Lakes region and Gulf Coast, including Michigan, Wisconsin, Illinois, Louisiana, Mississippi, Alabama, and Georgia had winter precipitation totals ranking among their ten wettest, as the green areas of the precipitation map indicate.

On the other side of the country, below-average precipitation occurred from the West Coast through the Northern Plains and Rockies, where drought conditions continue to persist. Across many parts of the West and Southwest, winter is the “wet season,” during which precipitation recharges soil moisture and refill reservoirs. Mountain snowpack is the frozen water supply that irrigates the semi-arid West from spring to fall. Unfortunately, the last two months have been especially dry in the West. (In the video below, climate scientist Deke Arndt talks about the importance of snowpack to Western water supplies.)

In addition to concerns over reservoirs and soil moisture, drought affects all parts of the environment and our communities. People may have to pay more for food as costs to irrigate crops and water animals rise. Drought can also destroy habitats—think salmon runs—and lead to a higher risk in wildfire activity. A second severe fire season would be a devastating consequence for the West, where above-average wildfire activity destroyed hundreds of thousands of acres in 2012.

Maps by Climate.gov team, based on U.S. Drought Monitor data and U.S. Climate Division data. Caption by Susan Osborne and Jake Crouch, adapted from the February 2013 National Climate Analysis. Reviewed by Jake Crouch.

Many areas across the world experienced higher-than average January monthly temperatures according to the latest statistics from NOAA’s National Climatic Data Center. The average global temperature for January 2013 tied with 1995 as the ninth-warmest January since record keeping began in 1880. It also marked the 37th consecutive January and 335th consecutive month with a global temperature above the twentieth-century average. The last below-average January temperature was January 1976 and the last below-average temperature for any month was February 1985.

The map above shows temperatures relative to average across the globe for January 2013. Shades of red indicate temperatures up to 7° Fahrenheit warmer than the 1981–2010 average, and shades of blue indicate temperatures up to 7° Fahrenheit cooler than the average. As the red-shaded regions demonstrate, Alaska, the eastern United States, southern Greenland, Uzbekistan, and Australia all saw above average January temperatures. Meanwhile, far northwestern and central Canada, the western United States, and a large swath of northern Eurasia were most notably below average as indicated by the blue-shaded regions.

The January nationally averaged maximum temperature was the highest ever recorded for Australia, at 4.10° Fahrenheit above the 1961–1990 average, besting the previous record set in 1932 by 0.20° Fahrenheit. The country set a new national record for the hottest day on January 7, with an average maximum temperature of 104.6° Fahrenheit, surpassing the previous record set on December 21, 1972. Every state and territory in Australia reported above average maximum and minimum temperatures for the month. Iceland was also warmer than average during January. The capital city of Reykjavik was 5.9° Fahrenheit above average, marking the warmest January since 1987 and the seventh warmest January since local records began in 1870.

For the ocean, the January global sea surface temperature was 0.74° Fahrenheit above the twentieth-century average of 60.5° Fahrenheit, the eighth warmest on record for January. Neither El Niño nor La Niña conditions were present across the central and eastern equatorial Pacific Ocean during January, with sea surface temperatures slightly below average across the eastern half of the equatorial Pacific. According to NOAA’s Climate Prediction Center, neutral conditions are favored over the next few months.

Map by Dan Pisut, NOAA Environmental Visualization Lab. Caption by Jessica Blunden and Susan Osborne. Adapted from the January 2013 Global Climate Report from NOAA’s National Climatic Data Center (NCDC). Reviewed by Jessica Blunden, NCDC.

[Update: Feb. 15, 2013] The original headline described January’s 0.14 inch precipitation anomaly as “near average.” We have revised the headline to conform to the language of the official ranking methods of NOAA’s National Climatic Data Center, under which January precipitation edged into the “above average” category.

Despite several snowstorms associated with cold-air outbreaks, average January temperatures across the contiguous United States weren’t especially cold according to the latest statistics from NOAA’s National Climatic Data Center. Although the average temperature was spot-on freezing—32.0° Fahrenheit—that was still 1.6° Fahrenheit warmer than the twentieth-century January average. Precipitation was regionally extreme, with contrasting areas having a top-ten-wet and top-ten-dry January, averaging out to a national total of 2.36 inches, just 0.14 inch wetter than the long-term average.

The maps above show the January 2013 temperature differences from the 1981–2010 average (top) and the percent of average precipitation (bottom) across the United States during the month. (Precipitation is the liquid water equivalent of all rain, snow, and sleet.) Reds and blues show temperatures up to 8° Fahrenheit warmer or cooler than average, respectively. The darker the color, the larger the difference from average. On the precipitation map, brown areas received less than 100 percent of their average January precipitation, and green areas received more than 100 percent of average.

As the red areas of the temperature anomaly map indicate, the eastern half of the contiguous United States saw warmer-than-average conditions in January. The Southeast was the most unusually warm region of the country; Georgia and Florida both had their 11th warmest January monthly temperatures. However, as the blue shades on the temperature anomaly map demonstrate, the western United States saw below-average temperatures throughout the month. Nevada had its ninth-coolest January on record, and Utah had its eighth coolest January on record.

Wetter-than-average conditions stretched from the Southern Plains to the Mid-Atlantic, where Louisiana, Mississippi, Tennessee, Michigan, and Virginia each had January precipitation totals ranking among their ten wettest. Unfortunately, the above-average precipitation generally missed the core drought areas of the central and southeastern United States, as the shades of brown on the map indicate. Drier-than-average conditions occurred along the West Coast, the central Rockies, and parts of the Northern Plains, Southeast, and Northeast. California, Connecticut, and Florida each had one of their ten driest Januarys. These wet and dry extremes averaged out to a near-normal January precipitation total for the contiguous United States.

These climate statistics and many others are part of NOAA’s National Monthly Climate Report. The National Climatic Data Center produces these monthly climate reports as part of the suite of climate services that NOAA provides government, business, and community leaders so they can make informed decisions.

Caption by Susan Osborne and Jake Crouch, adapted from the January 2013 National Climate Report from the National Climatic Data Center (NCDC). Reviewed by Jake Crouch, National Climatic Data Center.

Download large images: January-March | April-December | 2012

*Our original post, based on the Jan. 15 release of the 2012 Global Climate Analysis by the National Climatic Data Center, stated 2012 was the warmest La Niña year on record. Later analysis showed that 2012 was shy of the record by 0.02°C. For more information on the reason for the change, see our related article In Watching for El Niño and La Niña, NOAA Adapts to Global Warming.

After running the numbers for 2012, NOAA reported that the global average temperature in 2012 was 1.03° Fahrenheit above average, ranking it as the 10th warmest year since record keeping began in 1880. Although 2012 warmth did not top the charts, it was the third warmest “La Niña year” on record.

The maps above show temperatures relative to average across the globe for different periods January through March (top) and April through December (bottom). (The full year of 2012 is available via the link below the image). Shades of red indicate temperatures up to 7° Fahrenheit warmer than the 1981–2010 average, and shades of blue indicate temperatures up to 7° Fahrenheit cooler than the average.

La Niña is the cold phase of the El Niño-Southern Oscillation (ENSO), a natural seesawing in ocean temperature and the air pressure of the overlying atmosphere across the equatorial Pacific Ocean. ENSO fluctuates between warmer-than-average ocean surface waters (El Niño) and cooler-than-average ocean surface waters (La Niña) for months to even a year or two at time. The phase of ENSO has a powerful influence on the overall global temperature, and historically, it’s unusual for a La Niña year to be so warm.

Weak-to-moderate La Niña conditions were present in the eastern and central equatorial Pacific Ocean for the first three months of 2012, classifying 2012 as a “La Niña year.” ENSO-neutral conditions prevailed for the remainder of the year in the Pacific, and temperatures were above average across much of the rest of the globe. The warmth of the second part of the year offset the influence of the early-year La Niña, raising the global temperature up into the top-ten warmest.

Additionally, the average global land temperature was 1.62° Fahrenheit above the 20th-century average and ranked as the seventh warmest year on record. Because land surfaces generally have low heat capacity, temperature anomalies can vary greatly over land between months. Over the course of 2012, the average monthly land temperature anomaly ranged from +0.40° Fahrenheit in December +2.50° Fahrenheit in April.

The ocean, however, has a much higher heat capacity than land so its anomalies tend to vary less over monthly timescales. During the year, the global monthly ocean temperature anomaly ranged from 0.54° Fahrenheit in January to 0.99° Fahrenheit in September.

Maps by Dan Pisut, NOAA Environmental Research Lab, based on Climate Division Data from the National Climatic Data Center. Caption by Susan Osborne and Jessica Blunden, adapted from the December 2012 Global Climate Update from the National Climatic Data Center.

According to the latest statistics from NOAA’s National Climatic Data Center, the average temperature for the contiguous United States for 2012 was 55.3° Fahrenheit, which was 3.2° Fahrenheit above the twentieth-century average and 1.0° Fahrenheit above the previous record from 1998. The year consisted of the fourth-warmest winter, a record-warm spring, the second-warmest summer, and a warmer-than-average autumn.

The map above shows where the 2012 temperatures were different from the 1981–2010 average. Shades of red indicate temperatures up to 8° Fahrenheit warmer than average, and shades of blue indicate temperatures up to 8° Fahrenheit cooler than average—the darker the color, the larger the difference from average temperature.

Every state in the contiguous United States 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. On the national scale, 2012 started off much warmer than average, with the fourth-warmest winter (December 2011–February 2012) on record. The winter snow cover for the contiguous United States was the third smallest on record, and snowpack totals across the Central and Southern Rockies were less than half of normal.

Spring started off exceptionally warm, with the warmest March on record, followed by the fourth-warmest April and second-warmest May. The season’s temperature was 5.2° Fahrenheit above average, easily the warmest spring on record, surpassing the previous record by 2.0° Fahrenheit. The warm spring resulted in an early start to the 2012 growing season in many places, which increased water demand on the soil earlier than what is typical. In combination with the lack of winter snow and lingering dryness from 2011, the record-warm spring laid the foundation for the great drought of 2012.

The above-average temperatures of spring continued into summer. The national-scale heat peaked in July, which had an average temperature of 76.9° Fahrenheit, 3.6° Fahrenheit above average and the hottest month ever observed for the contiguous United States. The eighth-warmest June, record-hottest July, and a warmer-than-average August resulted in a summer average temperature of 73.8° Fahrenheit—the second-hottest summer on record. An estimated 99.1 million people—nearly one-third of the nation’s population—experienced 10 or more days of summer temperatures greater than 100° Fahrenheit.

Autumn and December temperatures were warmer than average, but not of the same magnitude as the three previous seasons. Autumn warmth in the western United States was balanced by cooler temperatures in the eastern half of the country, while December was warmer than average for the East. 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 United States’ record-warmest year by a wide margin.

Maps by NOAA climate.gov team, based on Climate Division Data from the National Climatic Data Center. Caption by Susan Osborne and Jake Crouch, adapted from the December 2012 National Climate Analysis from the National Climatic Data Center. Reviewed by Jake Crouch.

According to the latest monthly analysis from the National Climatic Data Center, the average global temperature for November 2012 was the fifth warmest November since record keeping began in 1880. It also marked the 36th consecutive November and 333rd consecutive month with a global temperature above the 20th-century average. The last below-average November temperature was November 1976, and the last below-average temperature for any month was February 1985.

The map above shows November temperatures relative to average across the globe. Red indicates temperatures up to 7° Fahrenheit warmer than the 1981–2010 average, and blue indicates temperatures up to 7° Fahrenheit cooler than the average. As indicated by the red areas on the map, most areas of the world experienced higher-than-average monthly temperatures, including far eastern Russia, Australia, the central and western United States, northern Africa, and most of Europe and western Asia. Meanwhile, central Asia, Alaska, much of western and central Canada, and the eastern United States were most notably cooler than average.

The average global land surface temperature was the sixth warmest on record for November with temperatures more than 2° Fahrenheit above the 20th-century average. The average global sea surface temperature was the sixth warmest on record for November at nearly 1° Fahrenheit above the 20th-century average. The central and eastern equatorial Pacific Ocean had sea surface temperatures slightly above average for the month, keeping neutral El Niño Southern Oscillation conditions in play. According to NOAA’s Climate Prediction Center, neutral conditions will likely continue through the winter and into the spring of 2013.

These warm November temperatures combined with record to near-record warmth over land from April to September and warmer-than-average global ocean temperatures contributed to the first 11 months of 2012 ranking as the eighth warmest such period on record. From January to November, the combined average global land and ocean surface temperature was over 1° Fahrenheit above the 20th-century average.

Map by Dan Pisut, NOAA Environmental Visualization Lab. Caption by Jessica Blunden and Susan Osborne. Adapted from the November 2012 Global Climate Report from NOAA’s National Climatic Data Center (NCDC). Reviewed by Jessica Blunden, NCDC.

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