Changing weather in the North-East of Thailand?

Weather in Khon Kaen - Thailand
Last week we had a lot of rain .... so much that many parts of Khon Kaen city were transformed into public swimming pools. The days were gray & dark. Like yesterday ... dark sky and most of the day a slightly raining. It is was cool.

Last night it was more as cool ... bloody cold! Sleeping without airco and even with a warm blanket, we did. Is the cold season beginning already? A bit early as I reckon it should start after Loy Kratong Festival at the end of November.