* WHAT. For the High Rip Current Risk, dangerous rip currents. For the Coastal Flood Advisory, up to one foot of inundation above ground level expected in vulnerable areas near the waterfront and shoreline. Localized moderate coastal flooding is possible during the second advisory Friday. For the Coastal Flood Watch, one to two feet of inundation above ground level possible in vulnerable areas near the waterfront and shoreline. * WHERE. Southwest Suffolk County. * WHEN. For the High Rip Current Risk, through Saturday evening. For the first Coastal Flood Advisory, from 8 PM this evening to 2 AM EDT Friday. For the second Coastal Flood Advisory, from 11 AM to 3 PM EDT Friday. For the Coastal Flood Watch, from Saturday morning through Saturday afternoon. * COASTAL FLOOD IMPACTS. Widespread flooding of vulnerable areas near the waterfront and shoreline, including roads, parking lots, parks, lawns, and homes and businesses with basements near the waterfront. Numerous road closures are likely, and vehicles parked in vulnerable areas near the waterfront will likely become flooded. Flooding will also extend inland from the waterfront along tidal rivers and bays. * RIP CURRENT IMPACTS. Life-threatening rip currents are likely for all people entering the surf zone. Anyone visiting the beaches should stay out of the surf. Rip currents can sweep even the best swimmers away from shore into deeper water. * ADDITIONAL DETAILS. Additional rounds of coastal flooding around the times high tide can be expected through at least the weekend.