But it usually only comes that far south in the winter months -- in the summer , the normal pattern is for the westerly wave to track north of afghanistan and miss pakistan completely .
These regions are under the influence of westerly winds , suggesting that the soot in question originated in europe .
这些地区受西风影响,因此研究人员正讨论这些烟灰可能来自于欧洲。
Pakistan 's meteorological department said the worst flooding in the country 's history was caused by unusually heavy monsoon rains and a westerly weather system entering pakistan .