How long was the drought that was caused by Elijah's prayers?
James and Luke say the drought lasted for three and a half years.
Yet according to the story in 1 Kings (the source for the New Testament writers), the drought lasted less than three years.
And Elijah the Tishbite, who was of the inhabitants of Gilead, said unto Ahab, As the LORD God of Israel liveth, before whom I stand, there shall not be dew nor rain these years, but according to my word. 1 Kings 17:1
And it came to pass after many days, that the word of the LORD came to Elijah in the third year, saying, Go, shew thyself unto Ahab; and I will send rain upon the earth. 1 Kings 18:1
And it came to pass in the mean while, that the heaven was black with clouds and wind, and there was a great rain. 1 Kings 18:45