Network with industry colleagues online. Message boards and mailing lists are a popular way to share ideas and strategies with your colleagues. There are many sites you can visit to pose industry-specific questions and discuss different destinations. Start with PCMA's site and participate in its Professional Forums, where you can pose questions to industry leaders. Check local climate conditions.
Nobody wants a rainy meeting.
Of course, you can't predict the weather months or years in advance, but you can find out what the general precipitation patterns are for different cities. The PlanSoft Network recently added a helpful search engine that allows you to identify different destinations based upon their seasonal weather patterns and the likelihood of rain. Check cities for citywides . If you visit the meeting, conference, and trade show search engines, you can find out which meetings will be in which cities for different date ranges. Then enter the city in which your event will be held and the date range.