You might say The Weather Channel Interactive (TWCi) saw some pretty sunny days this summer, especially during its “Mobile Month” from May 19 through June 20.

That’s when TWCi conducted a campaign to drive awareness about its mobile site. TWCi and Research In Motion (RIM) gave away a BlackBerry a day during the campaign, and they made sure winners received BlackBerrys that worked with their existing carrier.

The month-long promotion drew the highest number of registrants for any TWCi promotion. More than two-thirds of the registrants came via mobile devices, and mobile Web traffic during the promotion broke all records for the site, bringing 35% higher-than-usual traffic. More than 700,000 entries were made during the month-long promo.

TWCi expects to do another promotion along similar lines later this year or early next, said Derek Van Nostran, director of marketing. TWCi is available on carriers’ decks, but it also is trying to increase its off-deck traffic, he said.

TWCi used several mediums to drive traffic, including cable and online. The intention was to raise awareness, not drive subscription sales, but they did see a bump in subscriptions, he said. Subscription prices vary, but it averages around $2.99 a month.