You may have seen coverage in recent days of flooding in Peru. Whilst the situation for many areas of the country is serious, the vast majority of tourist areas remain unaffected. Our contacts on the ground advise that Machu Picchu town, Arequipa, Colca, Puno and the whole Cusco area are safe for travel, with little rain falling in those regions.
There has been some impact in Lima, however the popular tourist areas also remain unaffected and are safe for travel. Whilst water restrictions have been reported in some parts of Lima, the tourist infrastructure is setup to cope with conditions similar to these and the impact is minimal.
Up to date weather information can be found at http://www.senamhi.gob.pe/ (in Spanish).