There was an extensive northward migration of Painted Ladies in southern Oregon from at least between April 21 to April 25, 2019. Three different observers recorded migration rates ranging from between 68 northward in 2 hours on April 23 to 300 northwestward in 15 minutes on April 25. These butterflies are likely part of a second generation that originated farther south somewhere in California. From other reports I've received, conditions in California and southern Nevada have been so favorable that two generations of Painted Ladies grew and thrived there on an abundance of nectar and larval food plants.
-- Royce Bitzer, April 30, 2019