At least five billion-dollar weather disasters hit Earth during May. The most damaging of these was the historic flood disaster that killed at least 23 people in Central Europe in late May and early June. Record flooding unprecedented since the Middle Ages hit major rivers in Austria, the Czech Republic, Germany, Poland and Slovakia; the Danube River in Passau, Germany hit its highest level since 1501, and the Saale River in Halle, Germany was the highest in its 400-year period of record. Numerous cities recorded their highest flood waters in more than a century, although in some locations the great flood of 2002 was higher. Total damage from the flood is estimated to be $22 billion by Aon Benfield, making the flood the 5th costliest non-U.S. weather disaster in world history. The world-wide tally of billion-dollar weather disasters so far in 2013 is twelve, and the U.S. total is four, according to the May 2013 Catastrophe Report from insurance broker AON Benfield. This is double the number of billion-dollar disasters from their April 2013 report:

1) Floods in Central Europe, May - June, $22 billion
2) Drought, Brazil, 1/1 - 5/31, $8.3 billion
3) Tornado in Moore, OK and associated U.S. severe weather, 5/18 - 5/22, $5 billion
4) Drought in Central and Eastern China, 1/1 - 4/30, $4.2 billion
5) Flooding in Indonesia, 1/20 - 1/27, $3.31 billion
6) Flooding in Australia, 1/21 - 1/30, $2.5 billion
7 Tornadoes and severe weather, U.S., 5/26 - 6/2, $2 billion
8) Winter weather in Europe, 3/12 - 3/31, $1.8 billion
9) Drought, New Zealand, 1/1 - 5/10, $1.6 billion
10) Flooding in Argentina, 4/2 - 4/4, $1.3 billion
11) Winter weather, Plains, Midwest, Northeast U.S., 2/24 - 2/27, $1.1 billion
12) Severe weather in the Midwest U.S., 3/18 - 3/20, $1 billion

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