Simplify the following text for a Grade 12 native English-speaking person.
Original: The depression drifted southwestward because of the influence of two ridges to its north and with warm water temperatures and a favorable upper-level environment it strengthened into Tropical Storm Wilma on October 17 .
Simplified: The depression slowly moved southwestward , and in conditions that were good for strengthening , it strengthened into Tropical Storm Wilma on October 17 .