St. Petersburg, Florida is preparing for significant weather, including heavy rain and thunderstorms. The National Weather Service forecasts 2 to 4 inches of rain, with some areas potentially receiving more, which could lead to localized flooding. The thunderstorms are expected to bring gusty winds and frequent lightning, posing risks to outdoor activities and potentially causing power outages. This weather pattern is due to a low-pressure system in the Gulf of Mexico, increasing moisture and instability over Florida.