The 2012 drought disaster is rapidly worsening in severity, especially over the nation's agricultural heartland, according to the latest weekly U.S. Drought Monitor report, released Thursday.

While the area covered by the overall drought grew only slightly, the intensity increased alarmingly.

Nationally, the percentage of the country in "extreme" to "exceptional" drought – the two worst categories on the scale – jumped from 13.53% to 20.57%.

In other words, another 219,000 square miles was added to the area in extreme drought – an area slightly larger than the states of California and New York combined.

The overall percentage of the country in drought grew for the tenth week in a row, inching up from 63.54% to 63.86%.