What is this 喜迎十九大 event all over the recent Chinese news?
喜迎 → Welcome (with fond)
十九大 is an abbreviation for 中国共产党第十九次全国代表大会. The 19th National Congress of the Communist Party of China.

It's an upcoming event starting on October 18, 2017. As a bad custom, Chinese news media have started propagation about such important events since a few months ago. It'd be absolutely normal to see a truckload of these spams.