Updated 3:42 p.m.
Nixon's announcement Friday raises Missouri's total financial commitment to $150 million for a particularly devastating few months of natural disasters.
Nixon's budget director, Linda Luebbering, said the additional disaster aid will be funded by better-than-expected state tax revenues. Missouri ended its 2011 fiscal year Thursday with 5.9 percent growth.
The governor's previous allotment of $50 million for disaster aid was offset by cuts to education and other government services.
Luebbering said most of the additional money is necessary because of the May 22 tornado that killed 156 people in Joplin. But she said some portion also could pay for flooding aid.