Melissa is expected to significantly strengthen by late Friday and over the weekend, when the storm could become a hurricane as early as Saturday.

NHC wrote, "There will likely be just enough mid-level ridging building north of the storm to cause Melissa to begin moving very slowly westward, with that motion continuing through Tuesday."

"The tropical cyclone is expected to grow in size, and likely be a large and dangerous hurricane towards the end of the forecast period," the National Hurricane Center said.