To get estimates of panel and battery sizes I would want to ask someone with a set up in your area or a similar climate. I think they would have a feel for it. (I don't, sorry). In the meanwhile, the calculation tool at http://pvwatts.nrel.gov/
might be interesting to look at. It's been a while since I looked at this but from what I remember, it's for a grid connected setup but you can get it to give a calendar of a hypothetical typical year showing daily energy generation and from this you can see what a bad day looks like in your area and make sure your setup will still be effective on a bad day. Or if you want to have enough battery capacity to see you through a few bad days, you can see a worst case scenario where there is a succession of days with low generation. I don't know which would be cheaper: more panel and enough battery to see you through each day, or less panel and batteries to see you through a string of dull days. Bear in mind that lead acid batteries don't last very long so need replacing (or reconditioning?) on a regular basis, it is best not to drain them each day so you may need around double the capacity (if you want to store 50kWh for each day's usage, you may need to get more like 100kWh capacity batteries so they don't run down - I'm making these figures up to explain what I mean), and factor in the inefficiency of the batteries.
Like I say, I don't have practical experience and it would be better to find a neighbour doing a similar thing and ask them.