I used to do the same with my DSL connection. I noticed that the connection would drop or degrade when it rained sometimes. I started scraping the modem's sta

I used to do the same with my DSL connection. I noticed that the connection would drop or degrade when it rained sometimes. I started scraping the modem's status page with curl (the status page didn't require logging in), and graphing the SNR and data rates with gnuplot. Then I added temperature and precipitation data scraped from Weather Underground with a Python script to a separate CSV file. I did confirm that the SNR varied with temperature, with both daily and long-term cycles, assuming from thermal expansion/contraction in the lines and connections. I also observed dropouts when it rained. The strangest thing was that there was also a hard 12-hour cycle: every morning and evening, at the same times, the SNR would suddenly drop (in the morning) and go up (in the evening) by several dB. I never figured out what it was, but I always guessed it was some equipment turning on or off that caused interference on the line. One of the coolest parts actually was simply using GNU `date` to parse dates in natural language, so I could run something like `plotmodem 2 months ago to 1 month ago` to graph the data from the previous month, or `plotmodem 2 weeks` to see the last 2 weeks of data. I used `date` to convert natural-language dates to a standard format which I then parsed out of the CSV files with grep.