Jǐ tiān lái de liánxù jiàngyǔ zàochéng le shuǐzāi.
Several days of continuous rain caused flooding.
Tips
grammar
X来 (lái, since/over) attaches to time spans: 几年来 (over the past few years), 多年来 (over many years), 长期以来 (long-term). 几天来 is the few-days variant — common as a sentence opener in news writing.