NHC says 20 percent chance of storm over southwestern Caribbean Sea

(Reuters) - A broad low pressure system over the southwestern Caribbean Sea has a 20 percent chance of strengthening into a tropical storm over the next couple of days, the U.S. National Hurricane Center said on Tuesday. A tropical depression is likely to form by late this week or over the weekend while the low drifts generally northward, the Miami-based weather forecaster said. (Reporting by Koustav Samanta in Bengaluru; Editing by James Dalgleish)