Tropical Storm Erin is expected to strengthen into a powerful hurricane and could bring heavy rain, damaging winds and dangerous surf to the Leeward Islands and Puerto Rico this weekend. AccuWeather meteorologists say a turn toward the west-northwest is likely before Erin reaches the islands.

The outer bands of powerful Hurricane Erin lashed Puerto Rico, and the storm is approaching the Bahamas next. What can the mainland U.S. expect?

Forecasting a storm's intensity can be more challenging than predicting where it will make landfall. Forecast models, particularly for hurricanes, have improved, but they can still miss intensification or overstate it. Below is the intensity for Erin so far, and how experts at the Hurricane Center believe it will weaken or strengthen.

The National Hurricane Center expects Hurricane Erin to pass just north of the U.S. Virgin Islands and Puerto Rico this weekend, bringing the potential for flooding, hazardous seas, and tropical storm-force wind gusts as outer rainbands sweep across the region.

(Reuters) -Hurricane Erin, churning north in the Atlantic hundreds of miles offshore, is expected to trigger a dangerous storm surge and tropical storm conditions on Wednesday along North Carolina’s Outer Banks and other stretches of the U.