National Climatic Data Center
15 May 2008
NOAA: U.S. Has Cool April, Global Temperature Ranked 13th Warmest on Record
This past month was the coolest April in 11 years for the lower 48 United States, and fell into the lowest twenty-five percent of all Aprils based on records going back to 1895, according to an analysis by NOAA's National Climatic Data Center in Asheville, N.C.
The average April temperature, 51°F, during April was one degree below the 20th century mean, and was the 29th coolest, or 86th warmest, based on preliminary data.
The combined average global land and ocean surface temperatures for April ranked 13th warmest since worldwide records began in 1880.U.S. Temperature Highlights
Fifteen states, all in the Northeast, Great Lakes, and Mid-Atlantic regions, were warmer than average. New York ranked third warmest and Rhode Island, fourth warmest. Sixteen states, all west of the Mississippi, were cooler than average. Washington state ranked second coolest and Oregon fifth coolest. The monthly temperature for Alaska was 1.2°F (0.66°C) below average, the 43rd coolest April on record.
The varying temperatures kept the nation's overall temperature-related residential energy demand for April near average, based on NOAA's Residential Energy Demand Temperature Index.U.S. Precipitation Highlights
An average of 2.4 inches (61 mm) fell across the contiguous U.S. in April, which is 0.04 inches (1.1 mm) below average.
Iowa, Missouri, Virginia, and Wisconsin were much wetter than average for April, with Iowa and Wisconsin ranking fourth wettest on record. Arizona, California, Nevada, and Utah were much drier than average, with Arizona having the third driest April on record and California ranking fifth driest.
Twenty-one tornadoes were reported on April 4 across Louisiana, Mississippi, Alabama, North and South Carolina. The next week, 62 tornadoes ravaged Texas and Oklahoma between April 9-11. In Richmond, Va., heavy rains from April 20-22 brought the city's monthly total to 8.32 inches (211 mm).
Last month, Babbit, Minn., recorded 26 inches (66.0 cm) of snow, while 32 inches (81.3 cm) fell near the town of Virginia, Minn. This was the largest ever April multi-day snowfall in the Iron Range of northern Minnesota. The combination of snow melt and heavy rain continued to flood rivers and streams throughout northern Illinois and southern Wisconsin. At the end of April, major flooding was occurring on the Mississippi River between Rock Island, Ill., and Burlington, Iowa. Heavy rains in the upper reaches of the Lower Mississippi River spawned historic water levels downstream.
Bethel, Alaska, received 11.7 inches (29.7 cm) of snow during the month, bringing its seasonal total to 102.4 inches (260.1 cm), nearly twice the average and only the second time in the last 30 years with over 100 inches (254 cm) of accumulated snowfall. By April 19, Nome accumulated 105.4 inches (268 cm) of snowfall, ranking as the second-snowiest winter on record behind 1994-95.
Rainfall across parts of the Southeast improved drought conditions, with about 43 percent of the region classified in moderate-to-extreme drought at the end of April compared to 59 percent a month ago.
In April, precipitation was below normal across most of the West, compared to the 1971-2000 average. Areas in California and Nevada reported their driest March-April total precipitation. Mountain snowpack, however, remained healthy with most of the intermountain and Northwest regions reporting above normal snow packs by the end of the month.Global Highlights
April's combined global land and ocean surface temperature was 0.74°F (0.41°C) above the 20th century mean of 56.7°F (13.7°C).
Continued weakening of La Niña, the cold phase of the El Niño-Southern Oscillation, occurred during April. The global average ocean surface temperature in April was the ninth warmest on record, with a monthly anomaly of 0.59°F (0.33°C) above the 20th century mean.
Typhoon Neoguri brought torrential rains and flash flooding to Hainan, China, April 18. This was the season's earliest and perhaps the strongest typhoon to strike China since 1949.
Snow cover extent over Eurasia during April 2008 was the lowest on record for April, following a record low March extent, and a marked contrast to the record January expanse. For the Northern Hemisphere, this month was the eighth least extensive April snow cover extent in the 42-year historical satellite record.