Tornado hits France; unprecedented April heat in Europe

A rare EF-1 tornado with 73 - 112 mph winds (117 - 180 kph) hit Toulouse, France on Sunday, causing minor damage that included collapsed walls, uprooted trees, and cars moved out of place. The tornado touched down 15 - 20 km south of Toulouse in Southwest France at 7:10 pm local time, and baseball-sized hail (4 cm) also hit the region. According to the European Severe Weather Database (ESWD), this was the first tornado in France in 2012. French tornadoes are rare; there were just three tornadoes in the country in 2011. The European Severe Weather Database (ESWD) (as summarized by Wikipedia) lists 15 tornadoes for all of Europe so far in 2012. Most of the twisters (nine) were in Turkey. For comparison, an average of 495 tornadoes touched down in the U.S. during the period January - April over the years 2009 - 2011. A key reason for the lack of tornadoes in Europe is that the atmosphere is usually not unstable enough. Tornadoes require warm, moist, low-density air near the surface, and cold, dry, high-density air aloft to provide a lot of instability. The Baltic Sea and North Sea to the north of Europe moderate cold air flowing south from the pole, reducing the amount of instability over Europe.

Video 1. A rare French tornado kicks up dust near Toulouse, France on April 29, 2012.

Unprecedented April heat hits Central and Eastern Europe

A European heat wave of unparalleled intensity for so early in the year smashed all-time April heat records over much of Central and Eastern Europe on Saturday and Sunday. According to wunderground's weather historian Christopher C. Burt, and weather records researcher Maximiliano Herrera, new national April heat records were set in Belarus, Germany, Austria, and Poland, and hundreds of stations in Germany, Austria, France, Italy, Hungary, Moldova, Romania, Poland, Belarus, Ukraine, Lithuania, Latvia, Czech Republic, Slovakia, and Russia recorded their hottest April temperatures on record. Moscow hit 28.6°C (84°F) on Sunday, the hottest April reading in the city since record keeping began 130 years ago. The culprit for the heat wave and French tornado is a large low pressure system off the coast of France whose counter-clockwise flow has been pumping hot air from the Sahara Desert northwards into Europe. The low is expected to continue to bring unusually hot weather to most of Central and Eastern Europe for the remainder of the week.

New all-time April national heat records set over the past few days:

Poland: 31.7°C (89.18°F) at Tomaszow on 4/29
Germany: 32.2°C (90.0°F) at Munich on 4/28
Austria: 31.8°C (89.2°F) at Ranshoten on 4/28
Belarus: 30.4°C ( 86.7°F) at Zitovici on 4/29

Jeff Masters - Weather Underground