Several websites allow authors to share draft articles before publication. Searching these websites is important for preemption checking- you don't want an article identical to yours to be published in the middle of your writing process! Additionally, checking for forthcoming articles helps you address the most recent, cutting edge developments on your topic.
Here are some sources for searching for forthcoming articles:
Additionally, on both Lexis and Westlaw, you can run a search within the law reviews category and the click the bell icon to set up an email alert for any new articles that include your keywords.