Ask the Weather Guys: Is the California drought over?.
A: Drought in the United States has been assessed by a number of different measures over the last several decades.
The Palmer Index is based on a supply-and-demand model of soil moisture.
Of the two, supply is easier to calculate, as it is tied so obviously to precipitation.
The Palmer Index approximates this complicated nest of processes based on a formula that is based on recent temperature and precipitation.
In 1999, the National Oceanic and Atmospheric Administration and the U.S. Department of Agriculture developed the weekly U.S. Drought Monitor.
By this measure, drought in the U.S. fell to a record low this past week with only 6.1 percent of the contiguous 48 states experiencing drought conditions.
Most notable currently is the official end of the years-long drought in California that was announced last week.
The past winter was quite wet and has filled reservoirs in much of California to capacity.
In fact, there are now fears in certain parts of California that the spring snowmelt will induce flooding.