Major Highlights
NOAA REPORTS ABOVE AVERAGE WARMTH ACROSS THE U.S.
HEATWAVE AND TROPICAL SYSTEMS IMPACT NATION.
GLOBAL TEMPERATURE 2ND HIGHEST ON RECORD
The national temperature was warmer than average for the contiguous United States this past July resulting in part from a severe heatwave mid-month, according to scientists at the National Oceanic and Atmospheric Administration�s (NOAA) National Climatic Data Center (NCDC) in Asheville, N.C. Drier than average conditions prevailed across much of the Rocky Mountains, High Plains and the Mid-to-Upper Mississippi Valley. The global land surface temperature was 2nd warmest on record for the month. NOAA is part of the Department of Commerce.
U.S. Temperature:
NOAA scientists report that the average temperature for the contiguous United States for July (based on preliminary data) was 1.5 F (0.8 C) above the mean for 1895-2004. This was the 12th warmest July on record, with widespread warmth across the nation and much above average temperature in much of the Southwest and West. Nine states had much above normal temperature for the month with an additional 33 states above average. Only 6 states in the contiguous U.S. were near average and no state was cooler than average for July. Nevada had its second warmest July on record.
Most of the warmth occurred during a prolonged heatwave from the 11th to 27th of the month when mean temperatures in parts of the West exceeded 5-10 F above average. Over 200 cities broke daily high temperature records, with Denver, Colo., having its second warmest July since 1872 and equaling the all-time highest daily temperature record of 105 F. The record had stood since 1878.
Las Vegas, Nev., equaled its all-time record daily maximum temperature of 117 F, and had 5 consecutive days with temperatures exceeding 115 F. The warmth moved east through the month and was briefly replaced by cooler temperatures in the northern Plains in the last few days of July, setting new daily low temperature records in some places.
Temperatures across Alaska were above average during July, with a statewide temperature of x F (x C) above the 1971-2000 mean, ranking xth warmest since 1918.
U.S. Precipitation:
Precipitation was near average for the nation as a whole, with unusually dry conditions across the Rockies, High Plains and the Mid-to-Upper-Mississippi Valley. This contrasted with above average wetness in the Southeast, in large part related to landfalling tropical storm activity. Georgia and Alabama both had their 5th wettest July on record, while Colorado and New Mexico were 3rd and 4th driest, respectively. Salt Lake City, UT, had only 1% of its average July rainfall, while Great Falls, MT recorded only 7% if its normal July precipitation.
At the end of July, moderate-to-extreme drought (as defined by a widely-used measure of drought � the Palmer Drought Index) affected 17% of the West (Rockies westward), an increase of 6% from June 2005. The heatwave, combined with drier-than-average conditions in the Midwest also took a toll on the corn crop with drought declarations in both Wisconsin and Illinois. The dry weather in the West promoted wildfires, burning an acreage well above the 10-year average as of the end of July. A wet fall and winter resulted in extensive undergrowth, providing abundant fuel for the summer fires.
Tropical activity was unprecedented for July 2005 with 5 named storms developing: Cindy, Dennis, Emily, Franklin and Gert. Both Dennis and Emily became hurricanes, with approximately 32 deaths being blamed on Dennis as it moved through the Caribbean region. Cindy and Dennis made landfall in the US, Cindy as a tropical storm around Grand Isle, Louisiana, and Dennis as a major category 3 hurricane around Navarre Beach, Florida. Cindy�s major impact was rainfall and flooding across the southeastern states, while Dennis produced a large storm surge as well as rain-related flooding across the Southeast.
Globe:
The average global temperature anomaly for combined land and ocean surfaces for July (based on preliminary data) was 1.1 F (0.6 C) above the 1880-2004 long-term mean. This was the 2nd warmest such month since 1880 (the beginning of reliable instrumental records). The warmest July was in 1998 with an anomaly of 1.2 F (0.7C) above the mean. Land surface temperatures were 2nd highest on record for July with warmer than average conditions in Scandinavia, much of Asia, North Africa and the western US, while below average temperatures occurred in northern Canada and northern Alaska. Ocean temperatures were also 2nd highest on record.
Sea ice extent across Northern Hemisphere oceans, as measured by satellites, was lowest on record for July. The monthly extent was lower than the mean by more than a million square kilometers (9.02 million sq km in July 2005 compared to a July mean (1979-2000) of 10.1 million sq km). Other July months with low extents include 9.15 mill sq km for July 1995 (ranked 2nd lowest) and 9.22 mill sq km in July 2001 (3rd). For the last nine years, sea ice has been below the monthly mean for July. Sea ice generally reaches an annual minimum in September.
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NCDC / Climate Monitoring / Climate of 2005 / July / Help
