which means, you extension is dependent on the Google Weather data as well as your API... so if your server is down the extension does not work anymore... and if Google changes its data your API might not work anymore...
anyone who likes to use your extension should be aware of this...
btw. there are the following free weather APIs, which could be used by the web component...
you are scraping the Google page to get the data because there does not exist an official Google API...
and Google can change its page at any time without advance warning...
which means in this case your api might fail in scraping the data...
How do you define place if you have a place which exists in many countries, e.g. Birmingham (UK, Alabama:USA, Indiana:USA, Saskatchewan:Canada), and how do you confirm that the results returned are for that specific place?
place = Birmingham Alabama
should return Birmingham Alabama
place = Birmingham USA
should return Birmingham Alabama
place = Birmingham Canada
should return Birmingham SK Canada
It would be good if your extension included the city returned by the weather data, it has to be in the api response.....
This could be reason for your extension not working.
Google may detected unusual traffic from your ip which caused your extension to land on page which will include a CAPTCHA to land on the search results page.