Fly Infestation

Periodically we have a buzz of house flies congregating mostly in our kitchen and dining room.  They annoy us, get into the dishwashing tubs, rarely into the fridge where the coolness does them in or at least slows there metabolism.  They're back, too many for a fly swatter, too big for fly tape. 

I assume they laid eggs someplace in our house on a previous visit though I've not seen any larval forms preceding the presence of adult forms.  They seem to cluster most near our northern kitchen and dining room windows.  A quick survey of internet advice on control did not sound optimistic once the adults prevail.  We don't have a lot of exposed food around.  I could spray some Raid along the windows, probably will, but need to be careful to avoid food storage that we keep nearby.  In the past they have shown short life spans so the annoyance should dissipate but I'll do my best to hasten that chemically.