Hi, In terms of weather I find the only couple of months I don't recommend the Riviera Maya area is Sept and October. For those months I recommend the Dreams resorts in Puerto Vallarta or the Riu resorts in Los Cabos. The Pacific side of Mexico is much less likely to have storms in these time periods, otherwise for all other months of the year, it's always a gamble weather wise and if they get rain, it's usually only for an hour or two in the afternoon due to it being a very tropical place.