It is looking more and more likely that Tropical Storm Dorian will impact the United States. It has already caused significant flooding on the Caribbean island of Martinique, and is heading toward Puerto Rico and Hispaniola. 

Martinique ? pic.twitter.com/MPxiJYi5cc

— GREY (@Christianlebaco) August 27, 2019

Fortunately, Dorian has not strengthened much due to an abundance of dry air surrounding the system. And the latest forecast calls for it to remain below hurricane strength.

Previous forecasts from the National Hurricane Center called for Dorian to become a hurricane before impacting Puerto Rico and Hispaniola, but that has since changed due to the dry air and other environmental conditions being less than ideal.

Forecast models agree on where Dorian is going, but they disagree quite substantially on how strong it will be. What it comes down to is whether or not the system moves over the mountainous terrain of Puerto Rico or Hispaniola. If it does, significant weakening will likely occur because tropical systems essentially dislike high elevation.

If the center of the storm avoids land interaction while moving through the Caribbean, the level of concern for the Bahamas and the United States will rise quite a bit.

However, even if the storm does indeed miss the mountainous terrain in the Caribbean, there's no guarantee it'll become a hurricane. It could reach category 1 strength, but a strong tropical storm appears to be the most likely scenario once it approaches Florida's east coast. 

Regardless of exact strength, there will likely be impacts felt across Florida in the form of heavy rain, strong winds, dangerous rip currents and waves, storm surge, and isolated tornadoes if the current projection holds true.