___________________The current temperature here in Washington is minus seven degree Celsius. But the wind chill makes it feel like minus twelve. As VOA's Brian Allen explains a weather pattern called the Polar Vortex is causing the dramatic drop in temperatures. ________________________目前华盛顿的温度是摄氏零下7度,但寒冷的大风使人感觉像是零下12度.据美国之声的记者布莱恩`艾伦报道,这种急剧的气温下降是由于一种称为"北极涡流"的气候模式引起的.
