A federal science agency says the Gulf of Mexico coast from the Mississippi River to the western Florida panhandle remain the most vulnerable to oil from the BP Deepwater Horizon spill.

Texas’ coast has little chance of being struck but currents in the Gulf raise the probability to six to eight out of ten that the Florida Keys, Miami and Ft. Lauderdale will be hit.

Exactly where surface oil will spread in upcoming months can’t be known for sure, according to the National Oceanic and Atmospheric Administration. To make its estimates, NOAA scientists factor in historical wind and ocean current records, natural “weathering” (the chemical breakdown of oil) and human intervention to recover and remove the oil.

NOAA’s model considers 500 scenarios (possible outcomes). Each model assumes a 90-day oil flow rate of 33,000 barrels per day with a net flow rate ceiling of 60,000 barrels per day minus the daily projected amount being burned, skimmed or otherwise saved by humans. The model views oil as a shoreline threat only if it causes a dull sheen within 20 miles of the coast.