National Precipitation 2007
Precipitation in the United States during the first 11 months of 2007 was variable throughout much of the country with periods of excessive rainfall, especially across the central third of the U.S., and persistent and developing drought in the southeastern quarter of the country and the far western states. Winter was relatively wet in the South and North Central regions and relatively dry in the West and Southeast. In the spring, it was the driest March-May on record in the Southeast. The West was ranked 6th driest and the West North Central region had its 3rd wettest spring on record. In summer, the remnants of Tropical Storm Erin brought excessive rain to Texas, Oklahoma and Kansas, giving the South its wettest summer on record. Meanwhile, much of the Southeast continued to suffer in drought with its 11th driest summer on record, following the driest spring. Precipitation across the U.S. during the fall ranked 37th driest, although no regions ranked much above or much below normal.
For the contiguous U.S. as a whole, seven of the first eleven months of the year were drier than average. Combined with unusually warm temperatures in the Southeast, this exacerbated drought across much of the southeastern quadrant of the country. By August, over 40% of the contiguous U.S. was in moderate to extreme drought, as reported by the U.S. Drought Monitor. Increased October precipitation helped decrease this percentage to near 30% by the end of November. Nationally, year-to-date precipitation through the end of November was below the long-term mean, ranking as the 33rd driest year on record.
According to NOAA's Storm Prediction Center, preliminary estimates indicate that there have been nearly 1300 reported tornadoes from January- November 2007, which is slightly above the ten-year average and well above the 30-year average. Note that these numbers represent preliminary tornado reports and not the number of total tornadoes.
Spring in the central and southern parts of the country was punctuated by several severe weather outbreaks producing over 600 reported tornadoes and leading to nearly 50 deaths during March through May 2007. The first large tornado outbreak occurred on February 24, when 21 tornadoes were reported, mostly in Louisiana, Arkansas, and Mississippi. The next outbreak less than a week later, when over 70 tornadoes were reported across the Gulf Coast region, Missouri, Illinois and South Carolina on March 1. Later that month, 80 reported tornadoes occurred across the western Great Plains from Texas to Nebraska on the 28th. The next large outbreak occurred on May 5, when 111 tornadoes were reported from the Texas panhandle through Iowa, Nebraska, and South Dakota.
The most devastating tornado of 2007 was the EF5 tornado that hit Greensburg, Kansas shortly before 10 pm CDT on the night of Friday, May 4, 2007. The tornado, given the rating of five on the Enhanced Fujita scale, was the first to receive the EF5 classification and the first tornado to earn a 5-rating since the May 3, 1999 Moore/ Oklahoma City, OK tornado. At least ten fatalities were reported from this devastating storm, which damaged or destroyed an estimated 95% of the town of Greensburg. The tornado was on the ground for 22 miles (35.4 km) and had a maximum path width of 1.7 miles (2.7 km), moving north-northeast until it turned northward upon reaching Greensburg and later curved back to the west. Despite the tornado's strength, the 32-minute warning lead time given by the Dodge City NWS office and the quick reaction of the people of Greensburg kept the number of fatalities in the town of over 1600 persons down to a minimum.
(Information curtsey NOAA/NWS)