Extracting data from a webpage using lynx

So I am trying to parse out data from a log file on my router. Basically I want to extract the log file automagically and export it to a generic text document. Basically appending the new log file to the end of the last.

So far I have install lynx to view a webpage via the terminal.

sudo apt-get install lynx

Then to extract file I call the following command:

lynx -dump http://192.168.2.1/log.stm > log

I know that the > should actually be >> to append to the end. But the issue is I need to log in to the router for it to work....

Any help would be greatly appreciated.