根据R中的日期/时间范围连接数据

I have one file (location) that has an x,y coordinates and a date/time identification. I want to get information from a second table (weather) that has a "similar" date/time variable and the co-variables (temperature and wind speed). The trick is the date/time are not exactly the same numbers in both tables. I want to select the weather data that is I have one file (location) that has an x,y coor