A developing inventory of tornadoes in France

The analysis of 304 French tornadoes shows that the most struck areas are the northwestern part of the country, the south and the east. Tornadoes occur mainly in spring and in summer; August is the month when the frequency is maximum. Tornadoes move mainly from southwest to northeast, except in the south where the direction is sometimes south to north. Thirty-six killer tornadoes were listed (12% of the cases); most of them with an intensity greater or equal to F3. The occurrence is approximately 15-20 tornadoes each year in France, and the annual risk probability of significant tornadoes in France is 0.66 x 10(-5). This value is probably underestimated because all the tornadoes are not listed. (C) 2001 Elsevier Science B.V. All rights reserved.