Nope. Where else do you have an I2C bus plug? It just has to be on the I2C segment as the WeatherBoard, but not on the board itself. If you don't have any spare I2C bus connections available, then a solution is this:
I have found a bug in GroveWeatherPi.py code. If you attach a HDC1080 it is recognized OK. When it is read it works fine and stores the values internally and prints them out. The problem is the next section that checks the logical to see if a HTU21D is present - which it isn't so the else on the if sets the 2 values of the temperature and humidity to 0. These zeros are reported in the DB instead of the real readings from the HDC. Quick fix is to either remove the code for the HTU or comment out the else part of the conditional. A more elegant solution can be added that checks to see if one or the other sensor is present and if neither then set the temp and humidity to zeros.